New evidence from think tank Koi Tu has found at least 15 percent of Kiwi women are affected by mental distress during the perinatal period.

That number rises to 33 percent for Maori, Asian, and Pacific women.

Koi Tu Director Sir Peter Gluckman told Mike Hosking the research shows the consequences of a stressed mother for both them and their babies are serious.

He says unless we identify stress early in mothers, we will see more children fail at school, and more women commit suicide.

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