Ascertaining Non-Pregnancy

There should be no sexual intercourse with a pregnant woman until she gives birth, nor with a non-pregnant woman until she has one menstrual cycle

Abu Sa‘īd al-Khudri (may Allah be pleased with him) reported that the Prophet (may Allah's peace and blessings be upon him) said regarding the female captives of Awtās: ''There should be no sexual intercourse with a pregnant woman until she gives birth, nor with a non-pregnant woman until she has one menstrual cycle."