In order for a child to be eligible for adoption, his or her biological parents must terminate their parental rights. This is usually a court ordered form that's filed after the child is born. Termination of parental rights means that the biological parents are no longer legally obligated to care for the child.
Every state has its own laws addressing special cases in the termination of parental rights. Since the passage of the federal Adoption and Safe Families Act of 1997, state termination laws have limited time to resolve their termination. The termination process can still take years at a time. The average child spends over two years in the foster care system. In domestic infant adoption, this process doesn't take as long because the birth mother and father will voluntarily relinquish their rights after the child is born. Hawaii and Alabama are exceptions to that rule. Voluntary termination of parental rights, although faster, can also be revoked within a certain period of time by the birth mother after signing the voluntary consent.
What holds up state-ordered termination of parental rights is that Child Protective Services, after intervening with a household, tries to reunify the child with his or her family. This means parents may be ordered to take classes, attending counseling sessions, go to rehab or other such efforts to realign their lives with being a good parent. If this does not happen, the judge may terminate the parental rights. However, the finalization of this ruling may not make it through the system for months.