Infant Mental Health Association lobbyists say a parent and infant unit for mothers with mental health problems is urgently needed in the North Island.
New Zealand so far has only one such unit in Christchurch, which holds five beds and cots for South Island patients.
International figures used in the Healthy Beginnings Report released this year show the North Island should have four units to help mothers with mental health problems during pregnancy.
An association executive member, Tanya Wright says not helping mothers with mental health needs is affecting children in their adult life.
"There's good evidence that these mothers and their children struggle for years and years - even once an acute illness is past - because the right intervention hasn't been provided," says Ms