My wife cannot maintain the fetus due to the medical problems and so far her fetuses have aborted several times. Doctors recommended that my sperm and her egg fertilize (IVF procedure) in the laboratory and then the resulting embryo is transferred into the uterus of a surrogate mother to grow there. The wife of my brother in law was ready to accept the embryo in her uterus and finally a daughter was born by the grace of Allah. Please tell us who is the mother of the born child? Whether my brother in law and his father are maḥram (1) to the born child? In case they are not maḥram, if the wife of my brother in law breastfeeds the born child with her milk after this delivery according to the condition mentioned in the Practical Laws of Islam, whether the born child will be maḥram to them?
The owner of the sperm is the father of the born child, but there are different views between jurisprudential scholars about the mother of the born child. Some of them believe that the owner of the egg is her mother and in this case, your brother in law is her maternal uncle and his father is her maternal grandfather and they are maḥram to her.
Some others believe that the owner of the uterus, who delivers the born child, is her mother, and in this case your brother in law is maḥram to her because this daughter is his rabibeh (2), but his father is not maḥram to her.
But from my viewpoint, this born child has two mothers, it means either the owner of egg or the owner of uterus are her mother, therefore in this case, your brother in law and his father are maḥram to her.
In any case, breastfeeding of the wife of your brother in law from the milk produced on her chest from this very delivery, does not cause maḥramiat through Raḍāʿ (3), because one of the condition of being maḥram through Raḍāʿ is that the milk is from fahl (4).
1) Maḥram a person who is ḥarām for one to marry and/or it is permissible for one to see them without ḥijāb. There are three categories of maḥrams: a) blood-maḥrams like aunts and uncles; b) maḥrams by marriage like spouse, mother in law, father in law, son in law, daughter in law; and c) maḥrams through breast feeding.
2) Rabibeh: The daughter of one’s wife from the other husband.
3) Raḍāʿ : Raḍāʿ or riḍāʿa is a technical term meaning "the suckling which produces the legal impediment to marriage of foster-kinship”.
4) Fahl: It is the expression used to refer to the fact a mother’s milk was created by her husband’s semen.