One thousand pregnant women - half of whom are Maori - are wanted for a study on their sleep patterns and the few weeks after they have given birth.
The study, led by Massey University sleep researcher Leigh Signal with Sarah-Jaine Paine, aims to determine whether changes in sleep havean impact on the occurrence of depressive symptoms which may be a precursor to post natal depression.
A US study found evidence that women who had disturbed sleep in late pregnancy also had a longer labour and were up to five times more likely to have a Caesarean section.
Dr Signal said similar findings were also reflected in a previous New Zealand feasibility study of 34 women, which showed those who needed medical help during the birth of their babies lost significantly more sleep compared to those who had trouble-free births.
She said she wanted to hear from pregnant women in the lower North Island, across all ages of fertility and every socio-economic group.
The survey would involve women responding to a written questionnaire in late pregnancy, then a phone interview and a further written questionnaire after the birth of their baby.
"We need to understand how these relations work for all women and not just a particular sub population of women."
Dr Paine said that for this reason it was important to secure the support of Maori women whose experience of pregnancy could differ from non-Maori.
"For example Maori women were less likely to have medical intervention during labour and birth," Dr Paine said.
Dr Signal said women would be recruited from areas and district health boards covering Hawke's Bay, Mid-Central Health, Wairarapa, Whanganui, Hutt Valley and Capital and Coast.
"It's not to say that some of the sleep changes during pregnancy are not normal, but we do definitely want to know what the limits of those changes are."
