Birth Control Myths — Does It Cause Infertility? The Evidence

No. This is one of the most persistent and harmful myths about hormonal contraception, and decades of research consistently shows it is false.

Fertility returns after stopping birth control for all methods, though the timeline varies. After stopping the combined pill, patch, or ring, most women ovulate within 1–3 months. A large 2018 systematic review in Contraception analyzed over 14,000 women and found that pregnancy rates within 12 months of stopping hormonal contraception were equivalent to those in women who had never used it — approximately 83%.

After hormonal IUD removal, fertility returns within 1–2 months. Because the IUD's progestin acts locally with minimal systemic absorption, the brain's hormonal signaling recovers quickly.

After implant removal (Nexplanon), ovulation typically resumes within 1 month. Studies show rapid return to fertility regardless of how long the implant was in place.

Depo-Provera is the one method with a meaningful delay — the median time to ovulation return is about 5.5 months after the last injection, and it can take up to 12–18 months. This delay is temporary and does not indicate permanent harm. However, it's worth factoring into your planning if you want to conceive in the near future.

Why does the myth persist? Many women start birth control in their teens or twenties and stop it in their thirties when ready to conceive. Age-related fertility decline and previously undiagnosed conditions like PCOS or endometriosis — which were masked by hormonal contraception — can make conception harder. The birth control gets blamed, but the cause lies elsewhere.

The evidence is more nuanced than either "yes" or "no" — and the reality is that most women experience little to no clinically significant weight gain from hormonal birth control.

A landmark Cochrane review analyzing 49 studies found no strong evidence that combined oral contraceptives cause substantial weight gain. Most trials showed average weight changes of less than 2 kg (about 4.4 lbs) over 6–12 months — which falls within normal weight fluctuation and matches weight changes in placebo groups.

However, individual experience varies. Some women do notice water retention, bloating, or modest weight increases — particularly in the first few months. Estrogen can promote fluid retention, and progestin types differ in their androgenic and mineralocorticoid effects. If you've noticed weight changes, the specific formulation matters: drospirenone-containing pills (like Yaz and Yasmin) have mild diuretic properties and are less likely to cause water retention.

Depo-Provera is the notable exception. The injection is associated with greater average weight gain — roughly 2.5–4 kg (5.5–8.8 lbs) over the first year in some studies, with continued gradual gain over time. This appears to be actual fat gain, not just water retention, and may be related to Depo's effects on appetite and metabolism. Women who gain more than 5% of body weight in the first 6 months tend to continue gaining.

The hormonal IUD and implant show minimal effects on weight in large studies, though individual variation exists.

Practical takeaway: if weight change concerns you, it's a legitimate factor in choosing your method. But the fear of major weight gain should not deter you from highly effective contraception — for most methods, the effect is minimal.

The relationship between hormonal birth control and cancer is genuinely complex — it's not a simple good-or-bad story. The evidence shows both increased risk for some cancers and significant protective effects against others.

Breast cancer: large studies, including a 2017 Danish cohort study of 1.8 million women published in the New England Journal of Medicine, found a small but statistically significant increase in breast cancer risk among current and recent users of hormonal contraception — roughly 20% relative increase. However, the absolute risk increase is small: approximately 1 additional breast cancer case per 7,700 women per year. Risk returns to baseline within about 5 years of stopping.

Cervical cancer: prolonged use (5+ years) of combined oral contraceptives is associated with a slight increase in cervical cancer risk, likely because hormonal changes may increase susceptibility to persistent HPV infection. This risk also returns to baseline within about 10 years of stopping.

Ovarian cancer: hormonal birth control provides substantial protection. Combined pill use reduces ovarian cancer risk by approximately 40–50%, and this protection persists for 20–30 years after stopping. Given that ovarian cancer has a poor prognosis due to late detection, this is a significant benefit.

Endometrial cancer: combined pill use reduces risk by approximately 30–50%, with protection lasting at least 15 years after discontinuation.

Colorectal cancer: some evidence suggests a modest protective effect from oral contraceptive use.

The net cancer effect is favorable for most women — the protective effects against ovarian and endometrial cancer outweigh the modest breast and cervical cancer increases, particularly in women without strong family histories of breast cancer. Discuss your individual risk profile with your provider.

No. Long-term use of hormonal birth control is well-studied and safe for the vast majority of women. There is no evidence that extended use causes cumulative damage to your reproductive organs, hormonal system, or overall health.

The largest and longest studies on oral contraceptive safety — including the Royal College of General Practitioners' Oral Contraception Study, which has followed over 46,000 women since 1968 — actually show that long-term pill users have slightly lower overall mortality than non-users. This is largely driven by the protective effects against ovarian and endometrial cancer.

Your ovaries are not "using up eggs" faster or slower on birth control. Hormonal contraception suppresses ovulation, but it doesn't deplete your ovarian reserve any differently than natural cycling. The total number of eggs you have is determined before birth and declines at a genetically programmed rate regardless of whether you're ovulating each month.

The endometrium (uterine lining) returns to normal thickness and function within 1–3 cycles of stopping hormonal birth control. Years of thinning from progestin exposure does not cause permanent changes.

Certain conditions do warrant careful consideration for long-term use. The combined pill carries a small blood clot risk that accumulates with duration in women with additional risk factors (smoking, obesity, thrombophilia). Depo-Provera has bone density implications (see next question). And women with migraine with aura should avoid estrogen-containing methods due to stroke risk.

But for healthy women without contraindications, using hormonal birth control continuously from their teens through perimenopause — if they choose to — is medically supported. The fear of "giving your body a break" is not evidence-based.

Depo-Provera (depot medroxyprogesterone acetate) does reduce bone mineral density during use — this is a real effect, not a myth. However, the clinical significance is more reassuring than alarming, because bone density recovers after stopping.

The mechanism: Depo-Provera suppresses estrogen production to levels similar to early menopause. Since estrogen is critical for maintaining bone density, users lose approximately 5–7% of bone density over the first 2 years of use. This is comparable to the bone loss seen during breastfeeding.

The recovery: multiple studies show that bone density substantially or fully recovers within 2–3 years of stopping Depo-Provera. A key study in Obstetrics & Gynecology followed women for up to 7 years after stopping and found near-complete recovery of bone density at the spine and hip.

Clinical implications: the FDA added a black box warning in 2004 recommending that Depo use be limited to 2 years unless no alternative is adequate. However, ACOG and WHO take a more nuanced position — they state that the advantages of Depo generally outweigh the risks, even beyond 2 years, for most women. There is no evidence that Depo-Provera use increases fracture risk in reproductive-age women.

Special considerations: adolescents are still building peak bone mass, so prolonged Depo use during this window deserves careful discussion. Women with existing osteoporosis risk factors (family history, eating disorders, chronic corticosteroid use, very low body weight) should discuss alternatives.

To support bone health while on Depo: ensure adequate calcium intake (1,000–1,300 mg/day), maintain sufficient vitamin D (600–1,000 IU/day), and engage in weight-bearing exercise regularly. These are good practices regardless of your contraceptive method.

No. There is no medical reason to periodically stop and restart hormonal birth control. The idea that your body needs a "break" or "reset" from synthetic hormones is a myth with no evidence to support it — and following it can lead to unintended pregnancies.

This belief likely originated from early oral contraceptives in the 1960s and 70s, which contained much higher hormone doses and carried greater risks. Some providers at the time recommended periodic breaks out of an abundance of caution. Modern formulations contain significantly lower hormone doses, and decades of safety data have made this practice obsolete.

Taking a break actually introduces risk. Each time you stop and restart birth control, you go through an adjustment period with potential side effects — nausea, breakthrough bleeding, headaches, mood changes. You're also exposed to the highest risk period for blood clots (the first 3–6 months of use), which restarts with every new initiation. And, of course, you're at risk of unintended pregnancy during the break.

Some women want breaks to "check if my period still works." Your period will return after stopping hormonal birth control — the evidence consistently shows this. If your periods were regular before birth control, they'll be regular again. If they were irregular (due to PCOS, for example), they'll be irregular again — but that's the underlying condition, not birth control damage.

The only legitimate reasons to stop birth control are if you want to become pregnant, if you're experiencing side effects you want to evaluate, if you've developed a new contraindication (like migraine with aura for estrogen-containing methods), or if you simply don't want to take it anymore. All valid reasons — but none of them are about "breaks."

This is one of the most attention-grabbing birth control claims — and the evidence behind it is far weaker than headlines suggest.

The idea comes primarily from a small 2008 study published in Proceedings of the Royal Society B, which found that women on the pill showed altered preferences for the scent of MHC-similar men (MHC genes play a role in immune function). The theory: because the pill simulates pregnancy-like hormonal states, it might shift women's mate preferences toward genetically similar partners — potentially leading to relationship dissatisfaction when they stop the pill and their "natural" preferences return.

Why you shouldn't lose sleep over this: the original study had a small sample size and used artificial scent-preference tests, not real-world relationship outcomes. Several attempts to replicate the findings have produced mixed or null results. A large 2020 study published in Psychological Science involving over 500 couples found no meaningful difference in relationship satisfaction, sexual satisfaction, or attraction based on whether a woman was using hormonal contraception when she met her partner.

The MHC theory of mate choice itself is contested in humans. While MHC-based scent preferences have been demonstrated in mice, the role of MHC in human attraction is far less clear and likely dwarfed by cultural, psychological, and social factors.

Relationship satisfaction fluctuates for countless reasons — stress, life changes, communication patterns, personal growth. Attributing relationship dynamics to pill-induced pheromone shifts is an oversimplification that isn't supported by the weight of current evidence.

If you're experiencing changes in attraction or relationship satisfaction after starting or stopping birth control, hormonal effects on mood, libido, and energy are more plausible explanations — and these are worth discussing with your provider.