Even though the United States Supreme Court legalized gay marriage nationwide in June 2015, same-sex couples looking to adopt still face an uphill battle in certain states. Yet when it comes to raising healthy children, research on the subject confirms that having gay parents has virtually no effect on a child’s development.

Researchers from the Williams Institute at UCLA School of Law, the University of Amsterdam, and Columbia University have found that children raised by female same-sex couples are just as healthy physically and emotionally as kids from opposite-sex couples. “This study is the first to use a nationally representative survey to compare the two types of households by focusing only on those with parents that have been in a continuous relationship,” said lead author Dr. Henny Bos in a statement.

Transitions that affect the whole family, including parental separation and adoption, are especially hard on young children, no matter their parents’ sexual orientation. Some previous research has compared unstable same-sex families to stable heterosexual ones. To eliminate such bias, Bos’ research team made sure all couples included in their research were at the head of stable families.

Bos and her colleagues gathered data using the 2011-2012 National Survey of Children’s Health. The research team matched 95 female same-sex parent and 95 opposite-sex parent households with children between the ages of 6 and 17 based on parental and child characteristics, including parental age and level of education, children’s ages and levels of education, and family residence.

The findings showed no differences between children raised by same-sex couples and those reared by opposite-sex couples in terms of emotional difficulties, coping behaviors, and learning behaviors. Although children from same-sex households had similar outcomes as children from opposite-couple households, same-sex parents did have higher stress levels compared to opposite-sex couples.

“Future investigations might explore whether the cultural spotlight on child outcomes in same-sex parent families is associated with increased parenting stress,” said psychiatrist and co-author Dr. Nanette Gartrell, Visiting Scholar at the Williams Institute. “Some of our earlier studies have shown that lesbian mothers feel pressured to justify the quality of their parenting because of their sexual orientation.”

While this new study only took into account lesbian households, researchers from Bar-Ilan University in Israel conducted a similar study that examined how the brains of men and women changed when they became parents. This research included 89 straight moms and dads and 48 gay dads. MRI measurements revealed that the brain activity of gay dads was remarkably similar to that of heterosexual mothers and fathers. In fact, the connections between emotional and cognitive functions in the brains of gay dads grew stronger as they spent more time with their children.

Around six million children in the U.S. are being raised by at least one LGBT parent. Adoptions are regulated on a state-by-state basis, and some states have passed laws that allow adoption agencies, due to religious beliefs, to prohibit LBGT couples from adopting.

When it comes to parenting, evidence suggests cooperation and mutual support between parents are much more important than sexual orientation.

Source: NeJaime D, Gartrell N, Bos H, et al. Same-sex and Different-sex Parent Households and Child Health Outcomes: Findings from the National Survey of Children’s Health. Journal of Developmental and Behavioral Pediatrics. 2016.