©2018 WebMD, Inc. All rights reserved. eMedicineHealth does not provide medical advice, diagnosis or treatment. See Additional Information.

How Long Does it Take for Birth Control to Be Effective?

Reviewed on 11/29/2018

Ask a Doctor

My husband has been deployed with the Marines for the last nine months, and he’s coming home next week. With all the excitement and caring for my two little girls, I just remembered that I let my birth control lapse! I want to be intimate with my husband when he gets home, but we also can’t afford to get pregnant right now. How long does it take for birth control to be effective?

Doctor’s Response

Birth control pills are not always immediately effective. It depends on the type of pill you take, and when you start taking it in your cycle. You may need to use a backup method of birth control such as a condom or female condom for the first few days of using the pill.

If you are taking a combined oral contraceptive pill (COC), which contains both estrogen and progesterone, you are protected right away if you start the pills within 5 days after your period starts. If you start the COC any other time of the month, it takes 7 days to be protected from pregnancy and a backup birth control method is recommended.

Progestin-only pills (mini-pills) protect your from pregnancy after 48 hours, so backup contraception is recommended for the first 2 days.

If you miss a pill, talk to your doctor because you may need backup birth control for a time.

Health Solutions From Our Sponsors

Reviewed on 11/29/2018
Planned Parenthood. How effective is the birth control pill? 2018. 10 November 2018 .