Does the Catholic Church consider it sinful to be a surrogate mother?
The pain associated with sterility or loss can be heavy on married couples. So heavy that they start considering alternative means of obtaining a child. But according to the Catholic Church surrogate motherhood is gravely wrong:
Techniques that entail the dissociation of husband and wife, by the intrusion of a person other than the couple (donation of sperm or ovum, surrogate uterus), are gravely immoral. These techniques (heterologous artificial insemination and fertilization) infringe the child’s right to be born of a father and mother known to him and bound to each other by marriage. They betray the spouses’ “right to become a father and a mother only through each other” (CCC 2376; cf. CCC 2377-79).