Hello, and I would be happy to answer your question today. Femilon is a form of birth control, containing the hormones estrogen and progesterone in synthetic form. These hormones are normally present during a healthy woman s menstrual cycle, and during pregnancy. For that reason, accidentally taking any form of birth control pills during pregnancy has never been shown to have any ill effects on the fetus. So there is no reason to terminate the pregnancy or have any concerns about it because your wife accidentally took the Femilon. I hope that I was able to provide an adequate answer for you, and that this information was reassuring. Best wishes, Dr. Brown