Is the marriage contract valid, when a 3-week pregnancy abortion was done by the couple a week before the marriage contract because of their understanding that Nikkah is not valid during pregnancy?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad () is His slave and Messenger.

If the essential conditions for a valid marriage were fulfilled, then the marriage is valid. Among the most important of these conditions are: the offer and acceptance, the presence of a guardian (wali), and witnesses. The validity of the marriage is not affected by the fact that it took place after the abortion of the pregnancy.

There is a difference of opinion among the jurists regarding the ruling on marrying a woman who committed zina (fornication) before her womb has been cleared (istibra’). Some scholars held that such a marriage is permissible. This view was reported from Abu Bakr and Umar Ibn Al-Khattab and it is also the opinion of Al-Thawri, Al-Shafi'i and people of opinion (Aṣḥāb Al-Ra’y), as mentioned by Ibn Qudamah in Al-Mughni.

Moreover, even according to those scholars who prohibit such a marriage before istibra’, this does not justify aborting the pregnancy, even if it resulted from zina. Abortion in such a case is prohibited, and the stronger opinion among the jurists is that it is forbidden at every stage of the fetus’s development.

Therefore, it is obligatory to repent to Allah for the abortion, and it is likewise obligatory to repent from the act of zina.

Allah Knows best