Couples raising a child with developmental disabilities do not face a higher risk of divorce, especially if they have larger families, as compared to those couples raising typically developing kids, new research has found.

Parenting a child with a developmental disability involves challenges and rewards that are unique to each family and prior research has shown that parents of a child with a developmental disability tend to experience greater marital stress compared to peers raising typically developing children.

As a result, there has been "a conception that, in general, parents of children with disabilities are more likely to experience divorce, and we wanted to test that assumption", said first author of the study Eun Ha Namkung from University of Wisconsin-Madison, in the US.

The team used data from the Wisconsin longitudinal Study that has been following more than 10,000 men and women who graduated from Wisconsin high schools in 1957 and some of their siblings for more than 50 years.

The researchers found that about 22 percent of parents with a child with developmental disability experienced divorce over the span of the study.

They also found that among couples with children without any disabilities, the risk of divorce was lowest for couples with one child and increased with each successive child.

In contrast, the risk of divorce for parents of children with developmental disabilities remained unchanged with increasing family size.

"Our results clearly show that the effects of having additional children are different for families of individuals with developmental disabilities compared to the effects on the general population," said Namkung.

He suggested that "other children in the family may be a vital support system for parents coping with the care of a child with a developmental disability".

The study was published in the American Journal on Intellectual and Developmental Disabilities.