Do three menstrual periods after zina indicate the absence of pregnancy, thus making it permissible for the woman to marry, or is a medical confirmation of no pregnancy necessary? And is it possible for an ectopic pregnancy to occur with the continuation of menstruation, and for how long can such a pregnancy last?

Adultery is a major sin. Whoever is afflicted by it must repent sincerely and conceal it, and not inform anyone about it. The waiting period (iddah (definition)) for an adulteress is the same as that for a divorced woman: three menstrual cycles. If her waiting period ends and it becomes clear that her womb is free of pregnancy, she is not required to undergo a medical examination. She may marry immediately after the completion of the waiting period. Scholars have differed regarding the condition of an adulteress's repentance before marriage. The majority of scholars hold that it is not a condition, while the Hanbalis stipulate the completion of the waiting period and repentance from adultery. This is the view preferred by Sheikh al-Islam Ibn Taymiyyah.