Mich. Comp. Laws § 722.1904

Sec. 304. (1) Unless a surrogacy agreement expressly provides otherwise, both of the following apply: (a) The marriage of a surrogate after the surrogacy agreement is signed by all parties does not affect the validity of the agreement, the spouse's consent to the agreement is not required, and the spouse is not a presumed parent of a child conceived by assisted reproduction under the agreement. (b) The dissolution, annulment, or declaration of invalidity of the surrogate's marriage, the legal separation of the surrogate, or a judgment of separate maintenance concerning the surrogate after the surrogacy agreement is signed by all parties does not affect the validity of the agreement. (2) Unless a surrogacy agreement expressly provides otherwise, both of the following apply: (a) The marriage of an intended parent after the surrogacy agreement is signed by all parties does not affect the validity of a surrogacy agreement, the consent of the spouse is not required, and the spouse is not, based on the agreement, a parent of a child conceived by assisted reproduction under the agreement. (b) The dissolution, annulment, or declaration of invalidity of an intended parent's marriage, the legal separation of an intended parent, or a judgment of separate maintenance concerning an intended parent after the agreement is signed by all parties does not affect the validity of the agreement and, except as otherwise provided in sections 306, 308, and 309, the intended parent is a parent of the child.