Papua New Guinea's first female governor, Julie Soso, plans to introduce a bill to parliament early next year that would outlaw polygamy.
Governor Soso, who was elected to parliament in August, attended the launch of a report by the New Zealand Parliamentarians' Group on Population and Development this week, which addressed sexual and reproductive health in the Pacific.
She says custom once allowed for only tribal leaders to be married to more than one woman but says nowadays any man can have more than one wife.
She says it's an outdated practice but says poverty is driving some girls into polygamous marriages.
"Young girls are dropping school at early age and they're getting married to a married man and becoming the second or third wife, it's really uncontrollable so anybody can have two, three wives."
Governor Soso says polygamous marriages are not conducive to women making their own decisions.