The American Academy of Pediatrics, in a statement released Thursday, endorsed the right of gay and lesbian parents to get married and to foster and adopt children. Citing research that shows that children benefit when their parents, regardless of sexual orientation, are a legal and socially accepted family unit, the AAP says it is in children’s best interests that all parents be allowed to marry.

“What we have concluded is that sexual orientation . . . does not impact the well-being of children,” said Benjamin Siegel, co-author of the statement and the chairman of the AAP Committee on Psychosocial Aspects of Child and Family Health. “Children grow up in gay and lesbian families just as well as children in other families.”

The policy statement also calls for the repeal of the 1996 Defense of Marriage Act, saying it limits “access to federal benefits associated with civil marriage for gay and lesbian couples, and the right of gay and lesbian adults to adopt and provide foster care for eligible children.”

Siegel said the AAP estimates that as many as 2 million children in the United States are living with gay and lesbian parents. If the Defense of Marriage Act were repealed, he said, many of those parents would be able to get married and be recognized as a family. That would greatly reduce stress on the parents, he said, and in turn, on the children.

“There are laws that exist that impact these children,” Siegel said. “It’s best for children if they are raised with parents, either heterosexual or homosexual, that have recognized social, legal and economic stability. It’s just best for kids.”

The AAP has a history of supporting gay and lesbian parents. In 2002, it published a policy statement endorsing the legal adoption of a child by the co-parent or non-biological parent to give the child a permanent and legal relationship with the second parent, Siegel said.

In 2006, AAP published research on how laws on marriage, civil unions and domestic partnership affect the health and well-being of children. The latest statement is a culmination of the AAP’s efforts to establish the importance of legal family connections in childhood development.

“Society has changed and there’s a greater understanding of the life experiences of gay and lesbian people, both in the media and in politics,” Siegel said. “In the last five years there’s been a tremendous shift. More than 50 percent of young people in this country think marriage equality is appropriate for everyone.”