You can now count the American Academy of Pediatrics among the growing number of medical organizations that have announced support for same-sex marriage rights.

The AAP’s announcement comes days before the U.S. Supreme Court will hear arguments regarding same-sex marriage for the first time.

The organization of 60,000 pediatricians declared its support on Thursday after a four-year review of scientific studies that found “children’s well-being is affected much more by their relationships with their parents, their parents’ sense of competence and security, and the presence of social and economic support for the family than by the gender or the sexual orientation of their parents.”

The AAP’s announcement comes days before the U.S. Supreme Court will hear arguments regarding same-sex marriage for the first time. A recent Washington Post-ABC News poll showed that 58 percent of Americans now support marriage rights for gay couples.

The academy argues in its report that since the latest U.S. Census shows that gay and lesbian parents are now raising nearly 2 million children—and counting—same-sex couples should have access to the federal benefits that come with marriage to ensure the long-term security of their children.

However, a report in The New York Times included scientists who thought the evidence in the studies the AAP reviewed was “lackluster” and that the academy’s endorsement was “premature.” Skeptics say that the quality of national data on the issue is improving, but at a slow pace. A law school professor interviewed in The Wall Street Journal also expressed concern that the AAP was overstating its position that marriage was the only way for same-sex couples to get benefits that could also come from domestic partnerships.

The AAP seems more than comfortable with the available scientific data that found there was “no causal relationship” between a child’s development and his or her parents’ sexual orientation, and that the development of a child of a same-sex couple was based more on the child feeling wanted by two parents committed to shared parenting.

Based on that information, the academy recommended, according to the report:

Marriage equality for all capable and consenting couples, including those who are of the same gender, as a means of guaranteeing all federal and state rights and benefits, and long-term security for their children. Adoption by single parents, co-parents adopting together, or a second parent when one parent is already a legal parent by birth or adoption, without regard to the sexual orientation of the adoptive parent(s). Foster care placement for eligible children with qualified adults without regard to their sexual orientation.

The American Academy of Pediatrics joins several other national medical groups—the American Academy of Family Physicians, the American Psychiatric Association, the American Psychological Association, and the American College of Nursing—that have endorsed gay marriage.

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