Some states are not allowing the second gay parent, male or female, to be on the birth certificate whether the child is birthed or adopted.   The core argument is that in straight marriage the male contributes "sperm" to the child and therefore is the parent.  But one case where one woman had contributed an egg to the other for artificial semination was not enough to get the second mom on the birth certificate.  

Several of these cases are coming before the strongly conservative Supreme Court.   What will happen to gay parenting rights is of concern to many gay couples with children now or in the future.