A new study found if a mother experiences depression during pregnancy, the child becomes slightly more likely to be depressed during adulthood, BBC News reported.

For the study, University of Bristol researchers followed the offspring of more than 8,000 mothers who had either postnatal or antenatal depression during pregnancy. The study also found that medication to treat mental health could lower the risk of future depression.

"Depression in pregnancy should be taken seriously and treated in pregnancy," lead researchers Dr. Rebecca Pearson said. "It looks like there is a long-term risk to the child, although it is small."

When a mother experienced depression during pregnancy, the child was only 1.3 times more likely to become depressed after age 18. Despite the small risk, Pearson said it was not a casual link and needed to be researched further.

Professor Carmine Pariante, of King's College London's Institute of Psychiatry, agreed, but said the mental heath connection originates in the uterus.

"The message is clear - helping women who are depressed in pregnancy will not only alleviate their suffering but also the suffering of the next generation," he said.

Gregorio Maranon General University Hospital's professor Celso Arango agreed and also believed the stress hormones of the mother could affect the child in the womb.

"Women with depression would ideally be treated before getting pregnant, but if they are already pregnant when diagnosed with depression it is even more important that they are treated as it will impact on the mother and child," he said.

From 1991 to 1992, more than 14,000 mothers originally enrolled in a long-term health research project called the Avon Longitudinal Study of Parents and Children. The researchers used this data for their study, published in the journal JAMA Pediatrics.

The researchers also believe there are different factors attached either postnatal or antenatal depression. For example, they found social support to have a bigger impact in postnatal depression.