The New South Wales Government has increased the maximum penalty for performing female genital mutilation from seven to 21 years.

It has also introduced a new offence which will make it a crime to take a girl out of the state to have her genitals mutilated.

Community Services Minister Pru Goward says the new law will close a loophole which previously meant people who took their child overseas for the procedure could avoid being charged.

"It means that whether you are a doctor or a nurse with a scalpel, whether you are a backyard operator with a razor blade or you are a relative buying a plane ticket you are still guilty of female genital mutilation offences and you will face a severe penalty," she said.

The State Government says it expects to see more prosecutions as a result.

Minister for Communities Victor Dominello says it is difficult to know how widespread the problem is in NSW, because so much secrecy surrounds the practice.

"Female genital mutilation is a barbaric practice that belongs in the dark ages," he said.

"The NSW Government with these new laws sends a very clear signal that there will be a zero tolerance approach to this conduct."

NSW now has the toughest penalties in Australia, equal with Tasmania.

Health Minister Jillian Skinner says it is often health professionals who detect and report cases of female genital mutilation, and deliver long-term treatment for victims.

"Often the crime can go undetected for years, first coming to the attention of authorities when an adult presents to a clinician during pregnancy," she said.

"Through the Multicultural Health Communication Service, NSW Health will assist in the development of education campaigns for culturally diverse communities to enhance awareness of these increased penalties and the long-term health impacts on victims."