Emergency contraceptive pills are not an effective method of prolonged or long term birth control. The way these pills prevent pregnancy is by delaying ovulation. Hopefully, when the unprotected intercourse occurs, ovulation hasn’t occurred. Sperm can survive in the vagina for up to 3 days. ECPs can help delay ovulation by 3-4 days, thus allowing time for the sperm to die off. ECPs do not cause an abortion nor do they affect an already existing pregnancy.
So, to answer your question: yes, there is the risk of pregnancy even if you took the emergency contraception. If your period is more than one week late, do a pregnancy test. Depending on your result, you may want to call your doctor for more information on birth control or other options.
6. January 2012
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