See below: Levonorgestrel(Plan B) is not 100% effective in preventing pregnancy. If taken within 72 hours it will reduce the chance of pregnancy by 50%. It is somewhat less effective after 72 hours. You can take a repeat dose at day 5 although not approved for same. The copper IUD is the most effective emergency contraceptive.
Answered 3/25/2015
3.2k views
3 doctors weighed in across 2 answers
A doctor has provided 1 answer
A doctor has provided 1 answer
A doctor has provided 1 answer
9 doctors weighed in across 2 answers
90,000 U.S. doctors in 147 specialties are here to answer your questions or offer you advice, prescriptions, and more.
Ask your question