Authorities investigating after 12-year-old gives birth in Australia

A 12-year-old girl has given birth in Perth, prompting questions from police and other welfare agencies.

A spokeswoman said police were aware of the incident, and were working closely with the families involved and the Department of Communities.

In a statement, the department said it did not comment on individual cases to protect the privacy of children and families.

"If there are concerns that a child may have been sexually abused or is likely to be sexually abused, Communities undertakes a thorough assessment of the situation," the statement read.

"Where necessary, the matter will be referred to the WA police for further investigation and referrals to appropriate supports are provided."

The department said a coordinated response was required from state government and external support agencies, in both the short and long term.

According to the WA Health Department, in 2017, three girls aged 13 or under gave birth, with a similar figure for 2016.

In total in 2017, 91 women aged 16 or younger gave birth and the youngest registered mother was 12.

A dozen 12-year-old girls have given birth in WA since 1980.

The department says the teenage birth rate has dropped from 1.2 per cent in 1980 to 0.3 per cent in 2017.

File image of a swaddled newborn sleeping.