Health

The Scary Side Effects of Birth Control No One Tells You

37. Reduced Exercise Tolerance Hormonal contraceptives can subtly affect exercise tolerance by altering how the body uses oxygen and manages energy during physical activity. Estrogen and… Alina Yasinskaya - August 20, 2025

Birth control is used by over 65% of women aged 15-49 in the United States, making it a cornerstone of reproductive health. While these medications offer effective pregnancy prevention, they can impact multiple organ systems—including cardiovascular, neurological, and endocrine systems. Unfortunately, side effects often go undetected or are underreported, leaving many women unaware of potential risks. As birth control methods evolve and usage continues to rise worldwide, understanding the hidden dangers becomes ever more crucial. This article explores the lesser-known, sometimes frightening side effects that everyone should know about.

1. Blood Clots (Venous Thromboembolism)

1. Blood Clots (Venous Thromboembolism)
An x-ray view reveals a blood clot obstructing the veins in a woman’s leg as she winces in pain. | Generated by Google Gemini

One of the most serious side effects associated with estrogen-containing birth control pills is an increased risk of venous thromboembolism (VTE), which includes deep vein thrombosis (DVT) and pulmonary embolism (PE). Estrogen alters the body’s natural clotting mechanism, making blood more prone to clotting. According to the U.S. Food & Drug Administration, women taking combination oral contraceptives have a three to four times higher risk of developing blood clots compared to non-users.

A notable case is that of 22-year-old Erika Langhart, who tragically died of a massive pulmonary embolism after using a popular contraceptive. Early warning signs of blood clots can include sudden leg pain or swelling, unexplained shortness of breath, chest pain, or coughing up blood. Recognizing these symptoms early and seeking immediate medical attention is critical. While the absolute risk is still low for most women, it is essential to weigh these risks when considering estrogen-based birth control methods and to discuss personal and family history of clotting disorders with your healthcare provider.

2. Elevated Blood Pressure

2. Elevated Blood Pressure
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Oral contraceptives containing synthetic hormones, particularly estrogen and progestin, can cause blood vessels to constrict, leading to elevated blood pressure. This vascular constriction increases the risk of developing hypertension, especially in women who already possess risk factors such as obesity or a family history of high blood pressure. According to a study published in the journal Hypertension, women using oral contraceptives are significantly more likely to develop high blood pressure compared to non-users, with risk climbing alongside age and duration of use.

Comparative research confirms that users of hormonal birth control have higher average blood pressure readings than women who have never used these medications. Elevated blood pressure is often silent but can contribute to serious complications such as stroke, heart attack, and kidney disease. Because of this, experts advise that women taking any form of hormonal contraception have their blood pressure checked regularly—ideally before starting, then periodically throughout use. If significant changes are noted, discussing alternative contraceptive methods or lifestyle modifications with a healthcare provider is vital. Learn more from the Centers for Disease Control and Prevention.

3. Migraines and Headaches

3. Migraines and Headaches
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Hormonal fluctuations triggered by birth control, especially those containing estrogen, can significantly influence the frequency and intensity of migraines and headaches. The sudden changes in estrogen levels that occur with starting, stopping, or missing doses of oral contraceptives may serve as a powerful trigger for many women. According to the American Migraine Foundation, women who already suffer from migraines are particularly susceptible to experiencing more severe or frequent attacks when using hormonal contraceptives.

Real-world studies show that women using estrogen-based birth control are more likely to report headaches compared to non-users and those on progestin-only methods. In some cases, the headaches are mild and manageable, but for others, they can escalate into debilitating migraines with visual disturbances, nausea, or sensitivity to light. Medical professionals advise that if you develop migraines with aura (visual or sensory symptoms) while taking birth control, you should immediately consult your healthcare provider. This is because migraines with aura, combined with hormonal contraceptive use, can increase the risk of stroke. For additional guidance and support, visit the Migraine Trust.

4. Mood Swings and Depression

4. Mood Swings and Depression
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The synthetic hormones in birth control pills can alter neurotransmitter levels in the brain, such as serotonin and dopamine, which are directly involved in regulating mood. These neurochemical changes may lead to mood swings, increased irritability, or even depressive symptoms in some users. For certain individuals, these effects can be subtle, while for others, they may significantly impact daily life and relationships.

A notable study published in JAMA Psychiatry followed over one million women and found that users of hormonal contraception were more likely to be prescribed antidepressants and to receive a first diagnosis of depression compared to non-users. Adolescents were found to be particularly vulnerable to these risks. The reasons for this are complex and may involve both biological sensitivity to hormonal changes and individual mental health history.

Experts recommend that women track their moods and mental health symptoms closely after starting or changing birth control. Keeping a journal or using a mood-tracking app can help detect patterns and changes. If you notice persistent sadness, loss of interest in activities, or major mood fluctuations, it’s crucial to speak with a healthcare provider. Visit the Office on Women’s Health for more resources on depression and women’s health.

5. Decreased Libido

5. Decreased Libido
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Hormonal birth control methods, particularly those containing estrogen and progestin, can suppress the body’s natural production of androgens, including testosterone. Since testosterone plays a crucial role in sexual desire, this suppression can result in a noticeable decrease in libido for some women. The effect may vary, with some experiencing a significant drop in sexual interest, while others notice only subtle changes or none at all.

Comparative research, such as a study published in the Journal of Sexual Medicine, has shown that women using combined oral contraceptives report lower rates of sexual desire compared to those using non-hormonal methods or progestin-only contraceptives. The same study noted that intrauterine devices (IUDs) without hormones are least likely to impact libido, while injectable and implantable hormonal contraceptives may also contribute to reduced sexual drive. Factors like relationship satisfaction and underlying health issues can also play a role.

If you notice a persistent or distressing loss of sexual desire after starting or switching birth control, it is important to bring this up with your healthcare provider. Open discussion can help identify possible solutions, such as trying a different contraceptive method or addressing other contributing factors. For more information, visit the Planned Parenthood Sexual Dysfunction page.

6. Weight Gain

6. Weight Gain
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Weight gain is a commonly reported concern among birth control users, although the mechanisms can vary. Hormonal contraceptives, especially those containing progestin, may cause the body to retain more fluid, leading to a sensation of bloating and minor increases in weight. Additionally, these hormones can influence metabolic rate and appetite, potentially resulting in changes to body composition over time.

Clinical trials have produced mixed results regarding the relationship between birth control and weight gain. According to a systematic review published in the Cochrane Database of Systematic Reviews, most users do not experience significant weight gain; however, some individuals, especially those on injectable contraceptives like depot medroxyprogesterone acetate (DMPA), are at a higher risk. For instance, a study in Obstetrics & Gynecology found that DMPA users gained an average of 5.4 pounds over three years compared to non-users.

Because weight changes can be gradual and influenced by multiple factors, it is important to track your weight regularly when starting a new contraceptive. If you notice rapid or persistent weight gain, consult your healthcare provider to discuss alternative options and review possible underlying causes.

7. Breast Tenderness and Enlargement

7. Breast Tenderness and Enlargement
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Hormonal contraceptives often cause fluctuations in estrogen and progestin levels, which can directly affect breast tissue. These hormones promote fluid retention and stimulate breast glandular tissue, leading to sensations of swelling, tenderness, or even temporary enlargement. This effect is most common during the first few months after starting a new contraceptive and tends to resolve over time as the body adjusts.

Many women report breast discomfort shortly after beginning hormonal birth control, similar to the tenderness experienced before menstruation. According to the Mayo Clinic, this side effect is typically mild but can be bothersome for some. Wearing a well-fitted, supportive bra and avoiding caffeine and high-salt foods may help reduce symptoms. Applying a warm compress and taking over-the-counter pain relievers like acetaminophen or ibuprofen can also provide relief.

If breast pain becomes severe, persistent, or is accompanied by a new lump, it is important to consult your healthcare provider to rule out other potential causes. For ongoing discomfort, a switch to a lower-dose or non-hormonal contraceptive may be considered. Learn more about breast changes and management at the Breastcancer.org resource page.

8. Nausea and Digestive Upset

8. Nausea and Digestive Upset
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Oral contraceptives can cause a range of gastrointestinal side effects, most notably nausea and digestive discomfort. These symptoms are thought to arise from the influence of synthetic estrogen and progestin on the stomach lining and digestive tract motility. Nausea is especially common in the initial weeks of starting the pill but tends to subside as the body acclimates to the hormones.

Clinical trials have shown that women taking oral contraceptives are more likely to report nausea compared to those given a placebo. According to research published in the International Journal of Women’s Health, about 10-20% of new users experience mild to moderate nausea, while the rates among placebo groups are significantly lower. Some women may also notice bloating, stomach cramps, or changes in bowel habits.

To help reduce nausea, experts recommend taking the pill with food or at bedtime. Sipping ginger tea, eating small frequent meals, and staying hydrated can also offer relief. If symptoms persist beyond a few months or are severe enough to impact daily life, it’s important to consult your healthcare provider about alternative formulations or delivery methods. More tips are available from the Planned Parenthood guide to the pill.

9. Irregular Bleeding and Spotting

9. Irregular Bleeding and Spotting
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Hormonal contraceptives can disrupt the natural menstrual cycle, sometimes leading to irregular bleeding or spotting between periods—a phenomenon known as breakthrough bleeding. This is especially common during the first three to six months of starting a new birth control method, as the body adjusts to changing hormone levels. Both combined oral contraceptives and progestin-only pills are associated with this side effect, although it may be more frequent with the latter.

Prevalence rates vary, but according to the American College of Obstetricians and Gynecologists (ACOG), up to 30% of new birth control pill users experience some form of irregular bleeding. Spotting is often light and not usually a sign of a more serious problem. However, persistent or heavy bleeding can be disruptive and may indicate that your body is not tolerating the formulation well or that other underlying issues exist.

Most cases of breakthrough bleeding resolve on their own within a few months. If irregular bleeding continues beyond three cycles, becomes heavy, or occurs with other symptoms like severe pain, it’s important to consult your healthcare provider. Learn more about abnormal uterine bleeding and its management from WomensHealth.gov.

10. Skin Changes (Acne or Melasma)

10. Skin Changes (Acne or Melasma)
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Hormonal contraceptives can have complex effects on the skin, sometimes improving acne while at other times triggering new skin issues. Estrogen-containing pills often help regulate sebum (oil) production, which can decrease acne outbreaks for some women. However, certain progestin-dominant formulations may worsen acne by increasing androgenic activity. The impact depends largely on the specific hormonal balance of the contraceptive and the user’s unique skin chemistry.

Another skin-related side effect is melasma, also known as the “mask of pregnancy”—a condition characterized by brown or gray-brown patches, usually on the face. According to the American Academy of Dermatology, melasma can be triggered by hormonal contraceptives in susceptible individuals, particularly those with darker skin types or a family history of the condition. Both acne and melasma can be distressing and may persist as long as the contraceptive is used.

To manage these skin changes, experts recommend using gentle, non-comedogenic skincare products and daily sunscreen to prevent melasma from worsening. If symptoms are severe or unresponsive to over-the-counter remedies, consult a dermatologist for tailored treatment options. For more tips on managing contraceptive-related skin issues, visit Women’s Health Magazine’s guide to birth control and skin.

11. Hair Loss or Unwanted Hair Growth

11. Hair Loss or Unwanted Hair Growth
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Hormonal contraceptives can affect hair follicles due to their influence on androgen levels in the body. Some formulations, particularly those with higher androgenic progestins, may trigger hair loss (telogen effluvium) or, conversely, cause unwanted hair growth (hirsutism) in areas such as the face, chest, or abdomen. Estrogen-dominant pills tend to suppress androgens and may help reduce unwanted hair, whereas certain progestin-dominant options can have the opposite effect.

A patient case reported by the American Academy of Dermatology involved a woman who noticed significant thinning of her scalp hair several months after starting a new oral contraceptive. Her symptoms gradually improved after switching to a pill with lower androgenic activity. On the other hand, some women find that certain pills trigger coarse hair growth in new areas, which can be distressing and affect self-esteem.

If you experience sudden or severe hair loss, or if you notice new, thick hair growth in unusual places, it’s important to consult a dermatologist. These symptoms may be reversible with a change in contraceptive or require targeted treatment. Find more information and support at the National Alopecia Areata Foundation.

12. Eye Problems (Contact Lens Intolerance)

12. Eye Problems (Contact Lens Intolerance)
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Hormonal contraceptives can cause subtle changes in the composition and production of tears, leading to dry eyes and altered corneal shape. These changes can make contact lenses uncomfortable or, in some cases, intolerable. The disruption of the tear film, which keeps the eyes lubricated and healthy, may be more pronounced in women who already have borderline dry eye or who wear contact lenses for extended periods.

Studies referenced by the American Academy of Ophthalmology indicate that contact lens wearers on birth control are more likely to experience symptoms such as eye dryness, irritation, redness, and blurry vision compared to non-users. Some women may also notice that their lenses fit differently or that their vision fluctuates over the course of their cycle due to hormonal shifts.

If you develop new eye discomfort, increased dryness, or difficulty wearing contacts after starting birth control, it is important to visit an eye care professional. An ophthalmologist or optometrist can recommend specific lubricating drops, adjust your lens type, or suggest alternative contraceptive options. For more guidance, visit the Contact Lens Safety portal.

13. Liver Function Changes

13. Liver Function Changes
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Oral contraceptives are metabolized by the liver, and their long-term use can alter liver enzyme activity and influence the production of certain proteins. These hormonal changes may increase the workload on the liver, sometimes impacting how the organ processes other medications. Most users experience no major issues, but rare complications can occur, particularly with prolonged high-dose use or in those with pre-existing liver conditions.

Studies, including one published in the World Journal of Hepatology, have linked oral contraceptives to the development of rare benign liver tumors called hepatic adenomas. While these tumors are generally non-cancerous, in exceptional cases they can rupture or transform into malignancies. Symptoms that may indicate liver involvement include persistent upper right abdominal pain, yellowing of the skin or eyes (jaundice), unexplained fatigue, or sudden swelling.

Women with a history of liver disease or abnormal liver function tests should avoid estrogen-containing contraceptives. If you notice any concerning symptoms while on birth control, seek prompt medical evaluation. Regular checkups and liver function monitoring can help catch any problems early. For more information, visit the American Liver Foundation.

14. Gallbladder Disease

14. Gallbladder Disease
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Hormonal contraceptives, particularly those containing estrogen, have been associated with an increased risk of gallbladder disease, including the formation of gallstones. Estrogen can elevate cholesterol levels in bile, making it more likely for gallstones to develop. This risk is particularly notable in women who use birth control pills for several years or have additional risk factors such as obesity or a family history of gallbladder problems.

A clinical review published in the World Journal of Gastroenterology reported that women who used oral contraceptives had a 20-50% higher incidence of gallstone formation compared to non-users. This increased incidence is most pronounced during the first few years of use and may decrease with lower-dose formulations, but the risk remains elevated compared to those not using hormonal birth control.

Warning signs of gallbladder disease include sudden and intense pain in the upper right abdomen, pain that radiates to the back or right shoulder, nausea, vomiting, and sometimes fever or jaundice. If you experience any of these symptoms, seek immediate medical attention. For further information on prevention and management, visit the Mayo Clinic’s gallstones resource.

15. Reduced Bone Density

15. Reduced Bone Density
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Some progestin-only birth control methods, such as the injectable depot medroxyprogesterone acetate (DMPA), have been linked to reduced bone mineral density. This occurs because these contraceptives lower estrogen levels, a hormone essential for maintaining strong, healthy bones. Reduced estrogen can accelerate bone resorption, leading to weaker bones and an increased risk of fractures over time.

Comparisons between users and non-users highlight the impact of long-term progestin-only contraceptive use. According to a study published in the Journal of Osteoporosis, women using DMPA for more than two years showed significantly lower bone density at the hip and spine compared to those not using hormonal contraception. The good news is that, for many women, bone mineral density improves after discontinuing the injectable, but young women and adolescents are particularly vulnerable to long-term effects during their peak bone-building years.

To protect bone health, experts recommend regular weight-bearing exercise, adequate calcium and vitamin D intake, and avoiding smoking or excessive alcohol. If you have risk factors for osteoporosis or a family history of bone disease, discuss alternative contraceptive options with your provider. More strategies to maintain bone health are available at the National Institute of Arthritis and Musculoskeletal and Skin Diseases.

16. Allergic Reactions

16. Allergic Reactions
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Although rare, some women experience allergic reactions to components found in birth control methods, such as synthetic hormones, dyes, or binding agents. Hypersensitivity can manifest with a variety of symptoms, including skin rashes, itching, hives, or swelling. In some cases, reactions may be triggered by the materials used in contraceptive patches, rings, or intrauterine devices (IUDs), rather than the hormones themselves.

Real-life cases have been documented in medical literature and by the National Center for Biotechnology Information. One report described a woman who developed severe itching and urticaria within hours of taking her first oral contraceptive, which resolved after discontinuing the medication. Another case involved an anaphylactic reaction—a potentially life-threatening systemic response—after insertion of a levonorgestrel-releasing IUD. Such reactions, though rare, require immediate medical attention.

Urgent symptoms of a serious allergic reaction include difficulty breathing, swelling of the face or throat, dizziness, rapid heartbeat, or widespread hives. If you experience any of these severe symptoms after starting or using a contraceptive, seek emergency care right away. For more information about medication allergies, visit the American Academy of Allergy, Asthma & Immunology.

17. Changes in Appetite

17. Changes in Appetite
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Hormonal contraceptives can influence appetite by altering levels of estrogen and progestin, which interact with the brain’s hunger and satiety centers. Progestin, in particular, is known to stimulate appetite in some women, leading to increased cravings and a tendency to eat larger portions or snack more frequently. These changes can be subtle or significant, depending on the individual’s sensitivity to hormonal fluctuations.

Studies such as one reviewed in the Obstetrics & Gynecology journal have shown that women using certain hormonal contraceptives report higher rates of increased appetite compared to those on placebos. Appetite changes are most commonly noted with injectable and implantable progestin-only methods, but some users of combined oral contraceptives also experience these effects. Not everyone will notice a change, and for many the effect is temporary as the body adjusts.

To help manage appetite changes, experts recommend practicing mindful eating—paying close attention to hunger cues, eating slowly, and choosing nutrient-dense foods. Keeping a food journal can help identify patterns and triggers. If appetite changes are affecting your weight or well-being, consult your healthcare provider. For more mindful eating strategies, visit the Harvard T.H. Chan School of Public Health’s Mindful Eating Guide.

18. Sleep Disturbances

18. Sleep Disturbances
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Hormonal contraceptives can impact sleep patterns by altering the body’s levels of estrogen and progesterone—hormones that play a role in regulating circadian rhythms and sleep quality. These changes may lead to symptoms like trouble falling asleep, waking frequently during the night, or experiencing less restorative sleep. Progesterone has mild sedative effects, but synthetic versions may not mimic this benefit, resulting in sleep disruptions for some users.

Research, such as a study from the Journal of Sleep Research, has found that women taking hormonal contraceptives reported greater difficulty with sleep onset and maintenance compared to non-users. Other studies indicate that while some women notice improvements in premenstrual insomnia, others experience new or worsened sleep problems after starting birth control. Individual responses can vary widely based on hormone sensitivity and contraceptive formulation.

To improve sleep hygiene, experts recommend maintaining a consistent bedtime and wake-up routine, limiting screen time before bed, creating a cool and dark sleep environment, and avoiding caffeine in the late afternoon or evening. If persistent insomnia or fatigue develops after starting a new contraceptive, discuss alternative options with your healthcare provider. For more sleep strategies, visit the Sleep Foundation’s Sleep Hygiene Guide.

19. Increased Risk of Certain Cancers

19. Increased Risk of Certain Cancers
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The relationship between hormonal contraceptives and cancer risk is complex and multifaceted. Research shows that long-term use of estrogen- and progestin-containing birth control is associated with an elevated risk of certain cancers, particularly breast and cervical cancer. Estrogen can stimulate the growth of hormone-sensitive breast tissue, potentially increasing the risk of abnormal cell changes and malignancy, while prolonged exposure to both hormones may contribute to cervical cell changes caused by human papillomavirus (HPV).

A comprehensive meta-analysis published in The Lancet found that women who used oral contraceptives had a slightly higher incidence of breast cancer compared to non-users, especially among current and recent users. Similarly, the National Cancer Institute notes a higher risk of cervical cancer with extended use, while also pointing out that these risks diminish over time after discontinuation.

Because of these associations, regular screenings such as mammograms and Pap smears are crucial for early detection and prevention. Discuss your individual risk factors and screening schedule with your healthcare provider. For more information, visit the American Cancer Society’s guide to birth control and cancer risk.

20. Decreased Risk of Other Cancers

20. Decreased Risk of Other Cancers
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While hormonal contraceptives are linked to higher risks of some cancers, they are also associated with a significant reduction in the risk of ovarian and endometrial (uterine) cancer. The protective effect is believed to result from the suppression of ovulation and stabilization of the endometrial lining, which reduces the likelihood of abnormal cell changes in these tissues. The benefit increases with longer duration of contraceptive use and persists for many years after discontinuation.

Long-term studies, including data published in The BMJ, show that women who have used oral contraceptives are about 30-50% less likely to develop ovarian or endometrial cancer compared to non-users. A landmark study from the Lancet found that the protective benefit can last for decades after stopping the pill, with the strongest effect observed among long-term users.

Given the complexity of cancer risks and benefits, it is essential to discuss your personal and family history with a healthcare provider when considering birth control options. This helps ensure a choice that best balances your individual risks and advantages. For more details, visit the National Cancer Institute’s fact sheet on oral contraceptives and cancer risk.

21. Vaginal Dryness

21. Vaginal Dryness
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Hormonal contraceptives, especially those with low estrogen content or progestin-only formulations, can decrease natural vaginal lubrication by altering the body’s hormone balance. Estrogen supports the health and moisture of the vaginal lining, so any reduction can lead to dryness, discomfort during intercourse, and even increased risk of irritation or infection. Some women notice these changes soon after starting a new contraceptive, while others may develop symptoms with long-term use.

Prevalence data from the Journal of Sexual Medicine indicate that up to 20% of hormonal contraceptive users report moderate to severe vaginal dryness, compared to lower rates among non-users. This side effect can negatively impact sexual satisfaction and quality of life, but it is often overlooked or dismissed in clinical settings.

To manage vaginal dryness, experts recommend trying water-based or silicone-based lubricants during sexual activity. Products labeled for sensitive skin or “fragrance-free” are usually best tolerated. If discomfort persists, speak with your healthcare provider about adjusting your contraceptive method or exploring additional treatment options. For further information and product recommendations, visit Planned Parenthood’s vaginal dryness resource.

22. Reduced Fertility After Stopping

22. Reduced Fertility After Stopping
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While most women regain their fertility soon after discontinuing birth control, some may experience a temporary delay before normal ovulation resumes. This effect is especially noted with long-acting methods such as the injectable contraceptive depot medroxyprogesterone acetate (DMPA), where the return to fertility can take several months or even up to a year for some users. The delay is generally shorter with oral contraceptives, patches, and rings, with most women ovulating within one to three months after stopping.

A comparative analysis published in Fertility and Sterility found that over 80% of women who stopped oral contraceptives conceived within one year, a rate similar to non-users. However, injectable contraceptive users experienced a longer median time to conception, with some reporting up to 10 months of delayed fertility. These timeframes can vary based on age, overall reproductive health, and individual hormone metabolism.

If you have not conceived after 12 months of regular, unprotected intercourse (or after six months if over age 35), experts advise seeking a fertility evaluation. For more information about fertility after contraception, visit the American Society for Reproductive Medicine’s FAQ.

23. Changes in Body Odor

23. Changes in Body Odor
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Hormonal contraceptives can subtly alter the body’s scent by affecting sweat gland activity and the composition of skin oils. Estrogen and progestin influence the apocrine glands, which are responsible for producing the sweat that interacts with skin bacteria to create body odor. As a result, some women notice a change in their natural scent, which may become stronger or simply different after starting or switching contraceptives.

Anecdotal reports, such as those collected in discussions by the Healthline women’s health community, describe a range of experiences—from increased underarm odor to changes in vaginal scent. These effects are usually not medically concerning but can be embarrassing or distressing for those affected. In most cases, the body adapts over time, but some women find the change persists as long as they use hormonal contraception.

Hygiene adaptations can help manage these changes. Showering daily, wearing breathable fabrics, and using gentle, non-irritating deodorants or body wipes may reduce odor. If you notice a sudden, unusual, or foul smell—especially if accompanied by other symptoms such as itching or discharge—it’s important to consult a healthcare provider to rule out infection. For more on managing body odor, see the American Academy of Dermatology’s advice.

24. Dizziness or Vertigo

24. Dizziness or Vertigo
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Hormonal contraceptives can sometimes cause symptoms of dizziness or vertigo, likely due to their influence on blood pressure regulation, fluid balance, and certain neurotransmitters in the brain. Estrogen and progestin may cause changes in vascular tone or slightly lower blood pressure, occasionally resulting in sensations of lightheadedness or imbalance, particularly when standing up quickly or during the initial weeks of use.

Patient stories shared on platforms like the Medical News Today forums include women describing sudden bouts of dizziness, feeling off-balance, or even experiencing spinning sensations akin to vertigo after starting a new contraceptive. For most, these side effects are mild and temporary, subsiding as the body adjusts. However, for some, persistent dizziness can interfere with daily activities or signal an underlying issue, such as changes in blood pressure or an atypical response to the medication.

It’s important to seek medical attention if you experience ongoing, severe, or sudden dizziness, especially if accompanied by chest pain, fainting, vision changes, or headaches. These could be signs of more serious complications like blood clots or cardiovascular events. For more details on dizziness and when to get checked, visit the CDC’s resource on dizziness.

25. Chest Pain or Palpitations

25. Chest Pain or Palpitations
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Hormonal contraceptives can have direct and indirect effects on the cardiovascular system, sometimes leading to symptoms like chest pain or heart palpitations. These symptoms may arise from changes in blood pressure, alterations in electrolyte balance, or increased blood clotting risk associated with estrogen-containing formulations. While most women use birth control safely, those with pre-existing heart conditions or risk factors may be more vulnerable.

Real-world examples highlight the importance of vigilance. For instance, the Healthline women’s health section shares accounts of women who experienced new or worsening palpitations and mild chest discomfort soon after starting certain pills, which resolved after discontinuing or switching methods. In rare but serious cases, sudden chest pain can indicate a blood clot in the lungs (pulmonary embolism) or a heart attack—both of which require immediate medical care.

Urgent symptoms include persistent or severe chest pain, pain radiating to the neck or arm, shortness of breath, fainting, or a rapid, irregular heartbeat. If you experience any of these signs while using birth control, seek emergency medical attention immediately. For more information on cardiovascular symptoms and birth control, visit the CDC’s contraceptive methods guide.

26. Anxiety or Panic Attacks

26. Anxiety or Panic Attacks
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Hormonal contraceptives can influence the brain’s neurotransmitter systems, sometimes leading to increased anxiety or even panic attacks in susceptible individuals. Estrogen and progestin affect serotonin, GABA, and other chemicals that regulate mood and stress responses. For some women, the introduction or adjustment of these hormones creates a heightened state of nervousness, restlessness, or sudden episodes of intense fear that can feel overwhelming.

Mental health data, such as findings published in the BMJ, highlight an increased risk of anxiety and mood disorders in women using oral contraceptives, particularly among adolescents and those with a personal or family history of anxiety. Though most users will not develop severe symptoms, a subset may experience a noticeable uptick in anxious thoughts or panic symptoms after starting or changing their contraceptive method.

It’s important to monitor your emotional well-being and track any new or worsening symptoms, such as persistent worry, agitation, racing thoughts, or panic attacks. Keeping a journal can help you identify patterns and triggers. If anxiety or panic is interfering with your daily life, inform your healthcare provider promptly. For more resources and support, visit the Anxiety and Depression Association of America’s page on women and anxiety.

27. Increased Risk of Yeast Infections

27. Increased Risk of Yeast Infections
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Hormonal contraceptives, particularly those containing estrogen, can alter the delicate balance of bacteria and yeast in the vaginal environment. Estrogen increases glycogen production in vaginal cells, providing more fuel for yeast (Candida) to thrive. This disrupts the natural flora, making women more susceptible to developing yeast infections, which are characterized by itching, burning, and thick, white discharge.

Prevalence numbers cited by the International Journal of Women’s Health suggest that women using hormonal contraceptives experience yeast infections at a higher rate—up to 15-20%—compared to around 5-8% in non-users. The risk can be higher in those with additional factors such as diabetes, antibiotic use, or compromised immune systems.

Prevention tips include wearing breathable cotton underwear, avoiding douches and scented hygiene products, and changing out of wet or sweaty clothes promptly. Maintaining good genital hygiene and a balanced diet may also help. If recurrent yeast infections occur, discuss alternative contraceptive options with your healthcare provider. For more information on prevention and treatment, visit the CDC’s guide to genital yeast infections.

28. Decreased Muscle Mass

28. Decreased Muscle Mass
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Hormonal contraceptives, particularly those containing estrogen, can influence muscle protein synthesis and overall muscle maintenance. Estrogen may decrease the body’s ability to build new muscle in response to resistance training by modulating anabolic and catabolic pathways. This effect can be more noticeable in women who are highly active or engaged in strength-based sports.

Comparative studies, such as one published in the Journal of Strength and Conditioning Research, have shown that female athletes using oral contraceptives may experience less muscle gain and slower recovery from exercise compared to non-users. The differences are generally small for most recreational exercisers but may become significant for competitive athletes focused on maximizing strength and muscle mass. These findings underscore the importance of considering individual athletic goals when choosing a contraceptive method.

To counteract potential muscle loss, ensuring adequate dietary protein intake is crucial. Experts recommend at least 1.2-1.7 grams of protein per kilogram of body weight for active women, along with regular resistance exercise. If you notice a plateau or decline in muscle development while using birth control, consider consulting a sports nutritionist or your healthcare provider. For more on nutrition and muscle health, see the Academy of Nutrition and Dietetics’ protein guidelines.

29. Eye Vision Changes

29. Eye Vision Changes
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While uncommon, hormonal contraceptives can sometimes lead to visual disturbances, such as blurred vision, double vision, or changes in visual field. These symptoms are thought to result from fluid retention affecting the cornea, changes in blood flow to the eye, or—more rarely—serious complications such as blood clots impacting the retinal vessels or optic nerve. Women who experience migraines with aura while using contraceptives may be at increased risk of such visual side effects.

Case reports in the American Academy of Ophthalmology’s EyeNet Magazine have documented instances of women developing sudden vision changes, including loss of vision and visual migraines, after starting oral contraceptives. Although these events are rare, they can signal significant underlying issues, such as retinal artery or vein occlusion, which require immediate medical attention.

If you notice new or sudden changes in your vision—including persistent blurriness, flashing lights, blind spots, or vision loss—promptly schedule an eye exam with an ophthalmologist. These symptoms should never be ignored, as early intervention can prevent permanent damage. For more information on visual side effects and when to seek help, see the American Academy of Ophthalmology’s birth control and vision page.

30. Increased Risk of Stroke

30. Increased Risk of Stroke
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Estrogen-containing contraceptives are associated with an increased risk of ischemic stroke, particularly in women who have additional risk factors such as smoking, high blood pressure, or a history of migraine with aura. Estrogen can promote blood clot formation and may alter the function of blood vessels, increasing the likelihood of a clot blocking blood flow to the brain. While the absolute risk remains low for most healthy women, it is a serious side effect that should not be overlooked.

Comparative statistics published in the journal Stroke indicate that women using combined oral contraceptives have a two- to fourfold increased risk of stroke compared to non-users. The risk is highest in women over 35 who smoke or have poorly controlled hypertension. For every 10,000 women using these contraceptives, an estimated 2-4 will experience a stroke annually, compared to 1 per 10,000 among non-users.

High-risk groups—such as those with a history of blood clots, stroke, migraine with aura, or cardiovascular disease—should avoid estrogen-containing contraceptives. If you fall into any of these categories, discuss safer alternatives with your healthcare provider. More details are available from the American Stroke Association’s birth control and stroke resource.

31. Swelling (Edema)

31. Swelling (Edema)
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Hormonal contraceptives, especially those containing estrogen, can lead to fluid retention, resulting in swelling (edema) of the hands, feet, ankles, or face. Estrogen promotes sodium retention in the kidneys, which increases water retention and can manifest as noticeable puffiness or tightness in affected areas. This side effect is often most apparent during the first few months of starting a new contraceptive or during hot weather and periods of prolonged standing.

Many women have shared real-life examples of experiencing rings feeling tighter, shoes fitting more snugly, or waking up with puffy eyelids after beginning a new birth control regimen. According to the MSD Manual, mild edema is a common side effect and usually not dangerous, but it can be uncomfortable and affect quality of life. For most, symptoms improve as the body adapts, but persistent or severe swelling should be evaluated by a healthcare provider.

Tracking changes in your weight and body measurements can help you and your provider assess whether swelling is related to your contraceptive. Reduce salt intake, stay hydrated, and elevate your legs when possible. If swelling is sudden, severe, or accompanied by pain or shortness of breath, seek prompt medical attention. More guidance can be found at the CDC’s page on water retention.

32. Fatigue

32. Fatigue
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Fatigue is a frequently overlooked side effect of hormonal contraceptive use. The synthetic hormones in birth control pills, patches, or injections can influence the body’s natural energy cycles by affecting cortisol, thyroid hormones, and neurotransmitters involved in sleep and wakefulness. These hormonal shifts may lead to persistent tiredness, sluggishness, or a general lack of motivation, even in the absence of other obvious health issues.

Survey data published in the Journal of Women’s Health found that up to 15% of women using hormonal contraceptives reported moderate to severe fatigue, compared to lower rates among non-users. The effect may be more pronounced during the first few months of use or when switching between different types of contraception. Other factors—such as stress, poor diet, or inadequate sleep—can amplify these feelings of tiredness.

To manage fatigue, experts recommend maintaining a consistent sleep schedule, engaging in regular physical activity, and eating a balanced diet rich in iron and B vitamins. Staying hydrated and managing stress through relaxation techniques can also help. If fatigue is persistent or impacts your daily functioning, consult your healthcare provider to rule out other causes or consider alternative contraceptive options. For more tips, visit the CDC’s guide to energy and physical activity.

33. Increased Risk of Lupus Flares

33. Increased Risk of Lupus Flares
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Hormonal contraceptives, especially those containing estrogen, can exacerbate autoimmune diseases such as systemic lupus erythematosus (SLE) in some women. Estrogen is known to modulate immune responses, potentially triggering inflammation and worsening autoimmune activity. For individuals with lupus, this may lead to increased frequency or severity of flares, characterized by joint pain, skin rashes, fatigue, and organ involvement.

Patient reports and clinical observations published in the Lupus Foundation of America and Arthritis Research & Therapy highlight cases where women experienced a resurgence or intensification of lupus symptoms after starting estrogen-containing birth control. While some studies suggest that low-dose oral contraceptives may be safer for patients with stable, inactive lupus, the risk of flare remains a significant consideration, particularly in those with active disease or a history of blood clots.

Women with lupus should discuss contraceptive options thoroughly with their rheumatologist and gynecologist, weighing the risks and benefits of each method. Non-estrogen options or progestin-only methods may be preferable for some. Regular monitoring and prompt reporting of new symptoms are essential for managing disease activity. For more guidance, visit the Lupus Foundation’s birth control resource.

34. Increased Appetite for Carbohydrates

34. Increased Appetite for Carbohydrates
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Hormonal fluctuations triggered by birth control, particularly those involving estrogen and progestin, can lead to increased cravings for carbohydrates and sugary foods. These hormones interact with insulin and leptin, hormones that regulate hunger and glucose metabolism, resulting in a heightened desire for quick energy sources like bread, pasta, and sweets. This effect is similar to what many women experience in the days leading up to their period, but for some, it can persist throughout contraceptive use.

Comparative research published in the Journal of the Academy of Nutrition and Dietetics found that women on hormonal contraceptives reported higher carbohydrate intake and a greater frequency of sugar cravings than non-users. While these cravings are not inherently harmful, they can lead to unintentional weight gain or blood sugar fluctuations if left unchecked. Emotional eating or reaching for processed snacks may also increase during times of hormonal change.

To manage carbohydrate cravings, nutritionists recommend balanced meal planning with an emphasis on fiber-rich whole grains, lean proteins, and healthy fats to promote satiety. Keeping nutritious snacks on hand and practicing mindful eating can help curb impulsive choices. For more guidance, see the Harvard T.H. Chan School of Public Health’s carbohydrates nutrition page.

35. Skin Rashes

35. Skin Rashes
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Hormonal contraceptives can cause skin rashes as a result of allergic reactions to ingredients or due to hormonal shifts that affect skin sensitivity and immune response. Some women experience contact dermatitis or urticaria (hives) from the adhesives in contraceptive patches, latex in condoms, or components in rings and pills. Others may notice hormonal rashes, such as erythema multiforme or eczema-like eruptions, especially when starting a new method.

Examples of rashes reported in clinical case studies and by organizations like the American Academy of Dermatology include red, itchy bumps, blisters, or patches that appear on the chest, abdomen, arms, or face. In most cases, these reactions are mild and resolve with antihistamines or by discontinuing the offending product. However, rare but serious rashes—such as Stevens-Johnson syndrome—require immediate medical evaluation.

If you develop a new, persistent, or rapidly spreading rash after starting birth control, especially if accompanied by fever, swelling, or difficulty breathing, seek prompt medical attention. Mild reactions may be managed at home, but severe or systemic symptoms warrant a provider’s assessment to rule out allergies or other underlying conditions. For more on skin rashes and their causes, visit the AAD’s skin rash resource.

36. Increased Risk of Blood Sugar Changes

36. Increased Risk of Blood Sugar Changes
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Hormonal contraceptives, particularly those containing progestin, can influence glucose metabolism and insulin sensitivity. These hormones may impair the body’s ability to process sugar efficiently, leading to elevated blood glucose levels in some users. This effect is more pronounced in women with underlying risk factors for diabetes, such as obesity, family history, or polycystic ovary syndrome (PCOS).

According to data published in the Journal of Clinical Endocrinology & Metabolism, oral contraceptive users may experience mild increases in fasting glucose and insulin resistance. While these changes are usually not significant for most healthy women, long-term use of certain progestin-only methods has been associated with a slightly increased risk of developing type 2 diabetes, particularly in those predisposed to metabolic issues. The CDC also advises women with diabetes to choose contraceptives carefully and monitor blood sugar closely.

Women with diabetes or risk factors should regularly check their blood glucose and discuss contraceptive options with their healthcare provider. Maintaining a healthy diet and active lifestyle is also essential. If you notice symptoms such as excessive thirst, frequent urination, or unexplained fatigue, talk to your doctor. For more information, see the CDC’s contraceptives and diabetes guide.

37. Reduced Exercise Tolerance

37. Reduced Exercise Tolerance
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Hormonal contraceptives can subtly affect exercise tolerance by altering how the body uses oxygen and manages energy during physical activity. Estrogen and progestin may influence cardiovascular function, red blood cell production, and thermoregulation, which can in turn impact endurance, stamina, and perceived exertion. Some women report feeling more easily fatigued or less able to perform at their usual athletic level after starting hormonal birth control.

Comparative studies, such as those reviewed in the British Journal of Sports Medicine, indicate that while most recreational exercisers experience only minor changes, some athletes—especially those in endurance sports—notice a measurable reduction in maximal oxygen uptake (VO2 max) and prolonged recovery times. These effects may be influenced by the type and dosage of contraceptive, as well as individual hormone sensitivity and baseline fitness levels.

Experts recommend monitoring your stamina and physical performance after starting or switching birth control. Keeping an exercise log can help track changes in endurance, heart rate, and perceived effort. If you experience a persistent decline in exercise capacity, discuss alternative contraceptive methods or possible adjustments to your training regimen with your healthcare provider. For more information, visit the American College of Sports Medicine’s guide on birth control and athletic performance.

38. Changes in Taste and Smell

38. Changes in Taste and Smell
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Hormonal contraceptives can affect the senses of taste and smell by altering hormone levels that interact with sensory pathways in the brain and nasal tissues. Estrogen and progestin influence the receptors responsible for detecting flavors and scents, which can lead to subtle or noticeable shifts in sensory perception. Some women report foods tasting different, an increased sensitivity to certain odors, or even a metallic taste in the mouth after starting a new contraceptive.

Anecdotal evidence collected from user forums and health communities, including Healthline, describes experiences such as heightened sensitivity to perfume, aversion to previously enjoyed foods, or an unusual aftertaste with specific meals. While these changes are usually harmless and temporary, they can be disconcerting and may affect appetite or dietary habits.

Experts suggest keeping a log of any unusual changes in taste or smell after beginning a hormonal contraceptive. If these symptoms are bothersome or persist for several months, consult your healthcare provider, as they may recommend trying a different formulation. Tracking these changes can also help distinguish between medication side effects and unrelated causes. For more on sensory changes and hormones, visit the National Institutes of Health’s research summary.

39. Increased Sensitivity to Sunlight

39. Increased Sensitivity to Sunlight
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Hormonal contraceptives, particularly those containing estrogen, can increase the skin’s sensitivity to sunlight. This heightened photosensitivity raises the risk of sunburn and promotes the development of melasma—dark, patchy skin discoloration most commonly found on the face. Estrogen stimulates the production of melanin, the pigment responsible for skin color, which can become unevenly distributed when exposed to ultraviolet (UV) rays.

Comparative studies, such as those summarized by the American Academy of Dermatology, show that women on hormonal contraceptives are more likely to develop melasma and experience sunburn faster than those not using these medications. Individuals with darker skin tones or a family history of pigmentation changes are at particularly high risk. Even brief sun exposure can trigger or worsen discoloration in susceptible users.

To protect your skin, experts recommend daily use of broad-spectrum sunscreen with SPF 30 or higher, wearing hats and protective clothing, and seeking shade during peak sunlight hours. If you notice new or worsening dark patches or burn easily, consult a dermatologist for personalized advice. For more sun protection tips and information on melasma, visit the AAD’s sun protection guide.

40. Joint Pain or Stiffness

40. Joint Pain or Stiffness
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Some women experience joint pain or stiffness after starting hormonal contraceptives, though the exact mechanisms are not fully understood. These musculoskeletal symptoms may be related to hormonal effects on inflammation, connective tissue, or fluid balance within joints. Estrogen and progestin can influence the production of collagen and synovial fluid, which are essential for joint flexibility and comfort.

Patient surveys and anecdotal reports, such as those noted in the Journal of Clinical Medicine, indicate that a subset of users report new or worsening joint discomfort, particularly in the hands, knees, or lower back. While these symptoms are often mild and may resolve as the body adjusts, they can impact daily activities or exercise routines for some women. In rare cases, hormonal contraceptives may unmask underlying autoimmune or inflammatory joint conditions.

To manage joint pain or stiffness, consider modifying physical activity by incorporating low-impact exercises such as swimming or cycling, ensuring proper warm-up and stretching, and using supportive footwear. Over-the-counter anti-inflammatory medications may provide temporary relief. If symptoms persist or significantly interfere with movement, consult your healthcare provider. For more on managing joint health, visit the Arthritis Foundation’s management tips.

41. Sore Throat or Cough

41. Sore Throat or Cough
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Though uncommon, some women report upper respiratory symptoms such as sore throat or persistent cough after starting hormonal contraceptives. These side effects may be related to immune system modulation by synthetic hormones, minor allergic reactions to inactive ingredients, or increased sensitivity of the mucous membranes lining the throat and airways. Such symptoms generally occur soon after initiating a new contraceptive and are often mild and self-limited.

Case reports published in the Journal of Pharmacology & Pharmacotherapeutics describe instances where women developed sore throat, cough, or mild hoarseness following the use of oral contraceptives or contraceptive patches. In the majority of these cases, symptoms resolved after discontinuing or switching the method. However, it is essential to distinguish these minor symptoms from unrelated viral or bacterial infections, which are far more common causes of sore throat and cough.

If a sore throat or cough persists for more than a week, becomes severe, or is accompanied by other symptoms such as fever, wheezing, or difficulty breathing, consult your healthcare provider. They can help determine whether the symptoms are related to your birth control or require alternative treatment. For more on medication side effects, see the Mayo Clinic’s sore throat resource.

42. Increased Risk of Urinary Tract Infections

42. Increased Risk of Urinary Tract Infections
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Hormonal contraceptives can influence the urinary tract in ways that may increase susceptibility to urinary tract infections (UTIs). Estrogen and progestin can alter the vaginal flora and pH, reducing the presence of protective lactobacilli and making it easier for harmful bacteria to colonize the urethra. Additionally, some contraceptive methods such as spermicides and diaphragms, often used in combination with hormonal birth control, have been shown to further elevate UTI risk.

Epidemiological data from the European Journal of Obstetrics & Gynecology and Reproductive Biology indicate that women using hormonal contraceptives have a 20-30% higher incidence of UTIs compared to non-users. The risk is especially pronounced in those with a history of recurrent infections or additional risk factors such as sexual activity, dehydration, or certain anatomical variations.

To help prevent UTIs, experts recommend urinating before and after sexual intercourse, maintaining good personal hygiene, drinking plenty of water, and avoiding prolonged use of irritating feminine products. If you experience symptoms such as burning during urination, frequent urge to urinate, or lower abdominal pain, consult your healthcare provider promptly. For more prevention tips, visit the CDC’s UTI prevention guide.

43. Changes in Menstrual Flow

43. Changes in Menstrual Flow
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Hormonal contraceptives are designed to regulate menstrual cycles, but they can also cause significant changes in menstrual flow. Some women experience lighter periods or even amenorrhea (absence of periods), while others may notice heavier or more prolonged bleeding, especially during the first few months of use. These effects depend on the type and dosage of contraceptive and the individual’s underlying hormone balance.

Statistics from the American College of Obstetricians and Gynecologists (ACOG) note that up to 50% of women using progestin-only methods (like certain IUDs or implants) report lighter or absent periods within the first year. Conversely, about 10-20% of users experience heavier or irregular bleeding, particularly during the initial adjustment period. Most cases resolve by the third to sixth cycle, but persistent or severe changes may require medical attention.

It is important to track changes in menstrual flow and discuss any concerns with your healthcare provider, especially if you experience very heavy bleeding, bleeding between periods, or sudden loss of periods after regular cycles. Such symptoms may signal underlying conditions or the need for an alternative contraceptive. For more guidance, visit the Office on Women’s Health menstrual cycle resource.

44. Increased Risk of Cervical Erosion

44. Increased Risk of Cervical Erosion
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Hormonal contraceptives, particularly those containing estrogen, can induce changes in the cervical tissue known as cervical erosion or cervical ectropion. This occurs when the delicate glandular cells from inside the cervical canal spread onto the outer surface of the cervix, making it appear redder and more fragile. While cervical erosion is generally benign, it can cause symptoms such as increased vaginal discharge, spotting after intercourse, or mild pelvic discomfort.

Clinical examples cited in the Journal of Family & Reproductive Health describe a higher prevalence of cervical ectropion among women using combined oral contraceptives compared to non-users. Most cases are discovered incidentally during routine pelvic exams and do not require treatment unless symptoms are bothersome or persistent. In rare instances, cervical erosion can make the cervix more susceptible to infections or complicate the interpretation of Pap smear results.

Regular cervical screenings (Pap smears) are essential for all women, especially those on hormonal contraceptives, to monitor cervical health and detect any abnormal changes early. If you notice unusual discharge, bleeding after sex, or pelvic pain, consult your healthcare provider for evaluation. For more information, visit the American Cancer Society’s cervical screening guidelines.

45. Increased Risk of Blood Pressure Spikes During Surgery

45. Increased Risk of Blood Pressure Spikes During Surgery
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Hormonal contraceptives can complicate surgical procedures by increasing the risk of blood pressure spikes (perioperative hypertension) and affecting the body’s response to anesthesia. Estrogen and progestin can promote fluid retention, alter vascular tone, and interact with anesthetic agents, making it more challenging to maintain stable blood pressure during surgery. These effects are particularly concerning in women with pre-existing hypertension or other cardiovascular risk factors.

Case studies published in the Indian Journal of Anaesthesia and documented by the American Academy of Family Physicians highlight instances where women on oral contraceptives experienced significant blood pressure fluctuations and an increased incidence of postoperative complications. Although most healthy women tolerate surgery without incident, those using hormonal birth control may require closer monitoring and tailored anesthetic management.

Pre-operative guidance includes informing your surgical team about all medications, including birth control. Your physician may recommend discontinuing estrogen-containing contraceptives several weeks before major surgery to reduce the risk of hypertension and blood clots. Always discuss personalized risks and medication adjustments with your healthcare provider before any planned procedure. For more on surgical safety and contraception, see the American Society of Anesthesiologists’ medication guide.

46. Allergic Reactions to Device Materials

46. Allergic Reactions to Device Materials
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Some women experience allergic reactions to the materials used in contraceptive devices such as intrauterine devices (IUDs) or implants. These reactions are not caused by the hormones themselves, but by components like nickel, copper, plastic, or silicone. Allergic responses can range from localized irritation at the insertion site to systemic symptoms, depending on the individual’s sensitivity to specific materials.

Real cases reported in the Journal of the Turkish German Gynecological Association and highlighted by the European Journal of Obstetrics & Gynecology and Reproductive Biology include women who developed severe itching, swelling, or rashes after IUD insertion. In rare instances, systemic allergic reactions such as hives or even anaphylaxis have been documented. Symptoms may appear shortly after device placement or develop gradually over time.

Common signs of an allergic reaction to device materials include persistent pelvic discomfort, localized redness or swelling, unusual vaginal discharge, itching, or skin rashes. If you develop any of these symptoms after receiving an IUD or contraceptive implant, consult your healthcare provider promptly. Early recognition and device removal can prevent more serious complications. For additional information, visit the American Academy of Dermatology’s allergic contact dermatitis resource.

47. Increased Risk of Ectopic Pregnancy (After Discontinuation)

47. Increased Risk of Ectopic Pregnancy (After Discontinuation)
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Following discontinuation of certain hormonal contraceptives, there may be a transient increase in the risk of ectopic pregnancy—a condition where a fertilized egg implants outside the uterus, most commonly in the fallopian tube. The mechanism involves residual effects of hormones on tubal motility, which can impair the normal transport of the egg to the uterus. This is particularly noted with progestin-only methods, such as injectables and implants, which slow the movement of the fallopian tubes and alter the uterine environment.

Risk data published by the World Health Organization and in the European Journal of Contraception & Reproductive Health Care indicate that women who conceive soon after stopping progestin-only contraception have a slightly higher incidence of ectopic pregnancy compared to the general population. While the absolute risk remains low, it is an important consideration for those planning to become pregnant immediately after discontinuing birth control.

Urgent symptoms of ectopic pregnancy include sharp or stabbing abdominal pain, shoulder pain, dizziness, fainting, or heavy vaginal bleeding. These signs require immediate medical attention, as ectopic pregnancy can be life-threatening if untreated. For more details, visit the ACOG’s ectopic pregnancy resource.

48. Chest Tightness or Shortness of Breath

48. Chest Tightness or Shortness of Breath
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Chest tightness and shortness of breath are potential warning signs of pulmonary embolism (PE), a rare but life-threatening complication associated with hormonal contraceptive use, especially those containing estrogen. Estrogen increases the risk of blood clots, which can travel to the lungs and block blood flow, resulting in sudden respiratory symptoms. These events require immediate recognition and action, as delay in treatment can be fatal.

Real-world cases documented by the CDC and reported in the BMJ include young, otherwise healthy women who developed chest discomfort, rapid breathing, and unexplained shortness of breath after starting oral contraceptives. In these instances, prompt emergency care was critical to survival and recovery. Additional symptoms may include coughing (sometimes with blood), rapid heart rate, dizziness, or fainting.

If you experience sudden chest tightness, severe shortness of breath, or any of the above symptoms while on birth control, call emergency services immediately or go to the nearest emergency room. Rapid diagnosis and intervention are essential for preventing serious complications or death. For more information on blood clots and birth control, visit the CDC’s guide to DVT, PE, and contraceptives.

49. Changes in Sexual Orientation or Attraction

49. Changes in Sexual Orientation or Attraction
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Emerging research suggests that hormonal contraceptives may influence patterns of sexual attraction and even subtly affect perceived sexual orientation in some women. Hormones like estrogen and progestin can modify the brain’s chemistry and the way individuals respond to social and sexual cues, possibly altering preferences for certain traits or partners. Some studies propose that women on the pill may be drawn to different physical or personality attributes compared to their preferences when off contraception.

Anecdotal examples, such as those discussed in Psychology Today and user forums, describe women experiencing changes in attraction, shifts in sexual orientation, or altered romantic interests after starting or discontinuing birth control. These effects are highly individual and can be temporary or persist throughout contraceptive use. While the underlying biological mechanisms are still under investigation, some researchers believe that hormonal suppression of natural fertility cues could play a role.

If you notice unexpected changes in sexual attraction or orientation, open communication with partners and healthcare providers is important. Such shifts are normal and do not require intervention unless they cause distress. For more on the science of hormones and attraction, visit the National Institutes of Health’s research summary.

50. Cognitive Blunting or ‘Brain Fog’

50. Cognitive Blunting or 'Brain Fog'
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Some women report experiencing cognitive blunting, often described as “brain fog,” after starting hormonal contraceptives. This sensation may include trouble concentrating, forgetfulness, slowed thinking, and difficulty recalling words or information. The brain’s sensitivity to estrogen and progestin can influence neurotransmitters such as acetylcholine and dopamine, which are crucial for attention, memory, and executive function.

Cognitive studies, including research published in the Journal of Clinical Endocrinology & Metabolism, have found subtle changes in verbal memory and spatial skills among oral contraceptive users when compared to non-users. While most women do not experience significant impairment, a subset may notice mild but persistent mental cloudiness, particularly during periods of hormonal adjustment or when switching contraceptive formulations. Individual sensitivity and the type of hormones used can influence the degree of these effects.

To help maintain mental clarity, prioritize adequate sleep, regular physical activity, and stress reduction techniques such as mindfulness or meditation. Staying organized with lists and reminders may also be helpful. If cognitive symptoms are severe, persistent, or impact daily life, consult your healthcare provider about alternative contraceptive options or further evaluation. For more on supporting brain health, visit the CDC’s healthy brain resource.

Conclusion

Conclusion
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Recognizing the broad range of potential side effects associated with birth control is vital for safeguarding your health and well-being. Many symptoms may go unnoticed or be dismissed, but proactive monitoring and open communication with healthcare professionals can make a substantial difference. If you experience any unusual or persistent symptoms, seek timely medical advice and discuss every concern with a qualified provider. Staying informed empowers you to make safe, personalized decisions about contraception. For more on navigating your options and understanding side effects, visit the Office on Women’s Health birth control resource and the CDC’s contraception page.

Disclaimer

Disclaimer
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This article is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a licensed healthcare provider regarding any medical concerns. For more information, visit the MedlinePlus medical disclaimer.

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