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Teen Pregnancy/Chances of pregnancy?


Ok so I was on birth control but i missed a few pills so i decided to stop taking it and wait to start a new pack. On January 11(exactly 2 weeks into my cycle so possibly ovulating) I had unprotected sex. The next day I was able to get the morning after pill. But contrary to popular belief plan b does not prevent fertlization or implantation it only delays ovulation. Im trying to be patient while waiting to take a test but i am so anxious....what do you guys think?

Hey, O

I think the myth you're thinking of, is that Plan B doesn't work if conception and implantation has already occurred. In other words, if the train has left for baby town, plan B doesn't stop it.

But the reason why Plan B is so effective (and it is really effective), especially in the first 24 hours, is that there are a lot of steps to getting pregnant and they take time to happen. Conception is not an instantaneous thing and Plan B has the chance to intervene at a couple different points along the way. So you're right, if you hadn't already ovulated, Plan B would suppress that. If you had already ovulated then the drug would make it harder for the egg and sperm to move through the Fallopian tubes and also possibly make implantation harder to accomplish by changing the lining of your uterus. It basically works in all the same ways your normal birth control works because it uses some of the same hormones - just in a super high dose.

Here's a handy link for more info:

So I think that you did everything right and since you acted in the first 24 hours your chances of not being pregnant are going to be close to 95%. (WebMD thinks so too:

However, since it's always better to be absolutely sure, go ahead and take that pregnancy test, but don't stress out about it in the meantime.

Good luck and get back on those birth control pills :)


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Julia Fout


I can answer questions pertaining to pregnancy symptoms, likelihood of being pregnant, pregnancy prevention, your options once you discover you are pregnant, how to talk to parents, how to talk to partners, prenatal concerns, and emergency contraception.


I have a degree in Psychology and am working towards my Masters of Public Health. Both of these fields require an understanding of adolescent development, health behavior and health education. I am invested deeply in ensuring that teens have access to practical, fact-based information. To provide this I stay current by reviewing peer-reviewed literature, health trends and statistics, and the work of activists in the field of pregnancy, sex education, mental health and general well being.

BA in Psychology/minor in Education
MPH Candidate 2014

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