Can you take the pill 3 days after having sex?
For example if you have unprotected sex on friday, and take the pill on monday. Will it still function?
Your question is a little unclear. Assuming that you are asking about emergency contraception (also called Plan B) to avoid getting pregnant, the guidelines advise taking the pill within 72 hours of unprotected intercourse, but the medication does seem to have some efficacy if taken within 120 hours (5 days). However, you should know that these medications are not 100% effective. The risk at any given time of getting pregnant ranges from 0-30% depending on the woman's menstrual cycle; levonorgestrel, which is marketed under the name Plan B One-Step, reduces the risk of pregnancy to 2-3% (preventing about 50% of pregnancies). Another drug called ulipristal prevents about two thirds of pregnancies, and a copper IUD can also be used and is actually the most effective method. The efficacy of these drugs can also vary depending on weight and timing within the menstrual cycle. Given the range of options, you should call your doctor and discuss which of these methods would be appropriate for your case. If you are asking about a birth control pill, it is unlikely to function in this situation and you should discuss with your doctor more specifically about when you would expect to get protection from the pill. Generally, contraception does not begin until 1 week of starting the pill, and if you miss more than 2 pills you will need back-up protection for one week after restarting. As always, using condoms and another form of birth control is the best way to avoid unwanted pregnancies and to avoid sexually transmitted infections. You should discuss birth control options with your doctor as well as whether you should be checked for sexually transmitted infections including chlamydia, gonorrhea, syphilis and HIV.
This answer is for general informational purposes only and is not a substitute for professional medical advice.
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