ZocdocAnswersWhat happens if I begin my second pack of birth control pills on the wrong day?

Question

What happens if I begin my second pack of birth control pills on the wrong day?

Hello. I am a 19 year old female and I began taking birth control pills (Belara) on the first day of my period in July. I made the mistake of not writing it down and I completely forgot which day it was. I "think" it was on a Tuesday but i'm not very sure. I got very confused a month later when I had to start a new pack and I am pretty sure that I didn't begin it on the right day. You might need to know that I am sexually active and I would like to know how it could affect me in that way. Thank you.

Answer

I suggest that you schedule an appointment with your primary care physician or OB/GYN. Generally speaking, I think that the way I can help you is to explain how hormonal birth control such as these pills works. A typical pack of birth control pills starts off with 21 days of a pill that contains a mixture of estrogen and progesterone-like medications. These medications act to suppress ovulation which is its main method of preventing pregnancy. We generally have women start these pills on the first day of their period. However, the only reason to do this is to make it easier for them to remember when they started. There's no practical reason to start on that specific day. In fact, you could start these pills at any day during your cycle and should expect them to become effective at preventing pregnancy within less than a week. The last seven days of a pack of birth control pills contain only placebo. Placebo is simply just a sugar pill which is used to keep you on schedule and in the habit of taking a pill every day. The purpose of these pills is to give your body a break from the hormones and allow you to have a normal period. I would suggest that you schedule an appointment with your primary care physician or OB/GYN, or whoever you see for this issue. I think it's important for you to be as educated as possible on how your birth control pills work because the more you know the more likely it is that you will be able to avoid an unwanted pregnancy.

This answer is for general informational purposes only and is not a substitute for professional medical advice.

If you think you may have a medical emergency, call your doctor or (in the United States) 911 immediately. Always seek the advice of your doctor before starting or changing treatment. Medical professionals who provide responses to health-related questions are intended third party beneficiaries with certain rights under Zocdoc’s Terms of Service.