More than a third of pregnant women at Middlemore hospital were not screened for sexually transmitted diseases, even though guidelines say they should.
Details of a study are in the latest issue of the New Zealand Medical Journal.
Dr Alec Ekeroma says just 64% of pregnant women at the hospital were screened for sexually transmitted infections in 2009,which is too low.
He says STIs increase risks to the health of the mother and baby during pregnancy.
Dr Ekeroma says the screening needs to be taken seriously and the Ministry of Health needs to reinforce its guidelines.
The study also shows a higher proportion of Maori and Pacific Island women were screened compared to other groups.
