This is a hot topic, a common question I get often in practice, and something that has a lot of miss-information out there on it!
Spoiler alert – Long term oral contraception use does NOT impact future fertility
One of the studies on this topic was done evaluating women, average age of 30 years old, who had been on a birth control pill for an average of 8 years, meaning they started in their late teens to early 20’s. A very common demographic I see in my office wanting to get pregnant! The study was evaluating:
- changes to markers of ovarian reserve when on a birth control pill
- recovery of fertility + markers of ovarian reserve when coming off of a birth control pill
- how to distinguish a true low marker of ovarian reserve when on a birth control pill vs a false low (masked by the birth control pill)
- AMH (antimullerian hormone) – hormone produced by potential follicles in the ovaries, it provides an estimate into how many potential follicles are being produced each cycle . A great marker of ovarian reserve, had you had yours tested yet?
- Antral follicle count – a transvaginal ultrasound was done to visualize follicle production on each ovary. A good antral follicle count is anything between 3-8 follicles per ovary.
- FSH, LH, Estradiol, Progesterone – endogenous hormones crucial for healthy follicle development, ovulation and building a healthy uterine lining
What did the study find?
The study found that AMH levels began to climb as early as two weeks after stopping the birth control pill! There was a steady increase in AMH until around 2 months after stopping the pill where AMH levels seemingly found their peak and plateaued. A similar pattern was noted via ultrasound on antral follicle count and in serum levels of hormones (FSH, LH, Estradiol)
What can we take away from this?
Based off of the data and averages calculated from all participants in this study, hormones and fertility return on average around 2-3 cycles following cessation of an oral birth control pill.
Time to pregnancy can be briefly delayed by 2-4 months after stopping combined oral contraceptives, but conception rates after 12 months are equal when compared to other contraception methods (condoms included)
Some important things to consider here:
- the conclusion of this study is from the average of participants – there were outliers who fertility parameters hadn’t returned yet, or it turned out they had underlying PCOS that was undiagnosed all those years when on a birth control pill
- the study was measuring ovarian return to tested markers of fertility, but wasn’t looking at other aspects that may impact female fertility (structural, cervical mucous, endometrial receptivity, immune)
- Long term oral birth control pill use may not, in the average women, effect overall fertility when coming off of the pill, but there are other health concerns to consider with long term OCP use.
To summarize – the birth control pill does not have an impact on future fertility. However when on the birth control pill, there is no way to know what your own hormones are capable of at that time (since they are suppressed by the pill), if there is more serious fertility concerns (PCOS) that the pill may be hiding, or your own ovarian reserve may be declining (age + environment related) and there is no way to know until you are off the pill and trying to conceive. If it’s been a couple of months since coming off the pill, and periods haven’t returned, cycles are irregular or you are experiencing other hormonal concerns – come in and lets chat about it, do some investigations and get cycles returning to normal to be able to achieve that positive pregnancy test!
Landersoe, S.K., Petersen, K.B., Sorensen, A.L., Larsen, E.C., Martinussem T., Lunding, S.A., Kroman, M.S., Nielsen, H.S., Nielsen, H.S., Andersen, A.N. 2020. Ovarian reserve markers after discontinuing long-term use of combined oral contraceptives. RBMO.