How long and how heavy is normal for breakthrough bleeding?
Breakthrough bleeding occurs in about one-third of women when they begin using the birth control pill. It resolves in almost all women by the third month of use. If irregular bleeding persists after three months, you should consider using a different form of the pill. Breakthrough bleeding results from irregular shedding of the uterine lining as it adjusts to the new hormone environment induced by the pill. Usually the bleeding is light, but occasionally it can be as heavy as a menstrual period. It occurs more often in smokers, because smoking affects the way the pill is processed in the body. Breakthrough bleeding can be managed by taking the pill at precisely the same time every day. Sometimes the addition of an extra hormone pill is recommended, but usually women are advised to simply be patient while the bleeding resolves on its own.
