When an adult man commits Zina (adultery or fornication) with an adult woman, does adultery render some of her relatives unlawful for him to marry?

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When a man commits Zina (adultery or fornication) with an adult woman, he is forbidden to marry her mother or daughter and it also becomes prohibited that such a woman marries the adulterer's father or son, as would happen if they were lawfully married. An adulterer is forbidden to marry the adulteress’ sister unless the adulteress is sure that she is not pregnant and this can be ascertained by menstruating one time or until she has delivered her baby if she is pregnant. The same ruling is applied when he wants to marry her paternal or maternal aunt. 

When a man commits adultery with his wife’s sister, he has to refrain from having intercourse with his wife until her sister menstruates three times. This is according to Ahmad .

The opinion that unlawful sex renders some originally marriageable women unlawful to marry is related on the authority of ‘Imraan ibn Husayn Al-Hasan, ‘Ataa’, Taawoos, Mujaahid, Ash-Sha‘bi, An-Nakha‘i and Ath-Thawri . And, this ruling is adopted by the Hanafi and the Hanbali scholars .

Allaah Knows best.