This bill, known as the "Unborn Child Support Act," amends part D of title IV of the Social Security Act to expand the child support enforcement program. It mandates that states establish and enforce child support obligations for the biological father of an unborn child to the mother, upon her request. These obligations can commence from the first month of conception, if the mother so requests, and payments may be collected retroactively. The legislation specifies that a court will determine the payment amount, taking into account the best interests of the mother and child. Importantly, any measure to establish paternity for an unborn child requires the mother's consent and must not pose any risk of harm to the child. The bill defines an "unborn child" as a member of the species homo sapiens at any stage of development carried in the womb, and it limits the ability of states to waive these new provisions.