The birth control pill can contain a combination of estrogen and progestin or be progestin-only. The hormones prevent pregnancy and regulate your period; however, missing too many days in a row puts you at risk for pregnancy.
Pregnancy Risk---Hormone Pills
If you miss four of the hormone pills (the first 21 pills in a pack), you have an increased risk of becoming pregnant if you are sexually active. The Center for Young Women's Health Center recommends you use a secondary birth control or abstain from sex if this occurs.
Pregnancy Risk---Non-Hormone Pills
If you miss four of the non-hormone pills (the last seven pills in a pack), the Feminist Women's Health Center states that you do not have an increased risk of pregnancy.
Bleeding
If you miss pills, you might experience spotting or irregular bleeding, one of the side effects of your body readjusting to the hormones, according to the Feminist Women's Health Center.
Taking Missed Pills
The Feminist Women's Health Center states that if four pills are missed, you should take one pill every day until Sunday, then begin a new pack of birth control pills. Use backup contraception for two weeks. Skip any non-hormone pills you missed.
Protection
If you were sexually active when you skipped birth control pills and were not using another form of birth control, the Center for Young Women's Health recommends emergency contraception.
