A women's health specialist In Papua New Guinea says a poorly manufactured birth control pill could result in unwanted pregnancies.

Radio Australia's Firmin Nanol reports that the professor of gynaecology at the University of PNG's Medical School says a birth control pill being given to women is of poor quality.

Professor Glen Mola says the pill, Planak, made in Indonesia cannot guarantee them unwanted pregnancy.
 

He says it turns into powder when the packet is opened, before the pill is taken.

"Whoever has made these pills have not compressed them properly and has put no coating on them," he said.

PNG's health authorities say they do not know the existence of the faulty pills.

Health secretary Dr Clement Malau says health inspectors have been asked to investigate and have it replaced.