What is the ruling on continuing a marriage with a woman whose pregnancy from someone other than her husband was discovered after the marriage, given her claim of rape and her fear of her family?

If a fornicatress gives birth to her child less than six months after her marriage, the child is not attributed to the husband but to the mother. However, if she gives birth to the child six months or more after her marriage, then it is attributed to the husband. The agreement of the spouses to deny the child's lineage is not sufficient, because lineage is a right of the child that cannot be waived except through "li'an" (mutual imprecation).