When a person stops taking the birth control pill, the pill’s hormones quickly leave the body. Gradually, the body’s natural hormones will resume regulating the menstrual cycle. Most people have their first period about 2–4 weeks after coming off the pill. However, it can take up to 3 months for the natural menstrual cycle to fully reestablish itself.
In some cases, a hormone dysregulation may develop while a person is using the birth control pill, which will mask the symptoms. Anyone who finds that their cycle has not returned to normal after a few months should see a doctor.
Effects on pregnancy risk
Birth control pills work by preventing ovulation, which is the process by which the body releases an egg. The pills also thicken the mucus of the cervix. As a result, even if ovulation does occur, it is more difficult for sperm to reach the egg.
As birth control pills suppress ovulation, removing these hormones from the body can trigger ovulation. In theory, ovulation could occur straight after coming off the pill. In this case, immediate pregnancy is a possibility.
The actual timing of ovulation depends on when in the cycle a person stops using birth control pills, as well as their overall fertility.
Effects on fertility
A 2018 meta-analysis looked at 22 studies on people’s fertility after stopping the use of birth control pills. The authors concluded that:
- birth control pills do not affect long-term fertility
- the duration of use of birth control pills is not a significant predictor of fertility
- there is no significant delay in the return of fertility after stopping the use of birth control pills
An earlier study investigated the length of time that it took for fertility to return following continuous use of the birth control pill levonorgestrel for a year. Of the 187 participants who took part in the study, 98.9% began ovulating within 90 days of stopping the pill. The average time that it took the participants to return to ovulation was 32 days.
This finding suggests that although some users may experience a delay in fertility after stopping the birth control pill, most will quickly become fertile again.
In a second study investigating fertility following continuous use of levonorgestrel, 52% of the 21 participants who wanted to become pregnant did so within 3 months of stopping this pill. Within 13 months, 86% became pregnant. These pregnancy rates are similar to those of the general population.
Source Article from https://www.medicalnewstoday.com/articles/327130.php