The Indian government children's minister has proposed the introduction of mandatory tests to determine the sex of an unborn child in a bid to counter the disturbing levels of female foeticide.

Prenatal sex tests are officially illegal in India, a policy designed to stop so many unborn girls being aborted by parents desperate for a boy.

But in a speech late Monday, Women and Child Development Minister Maneka Gandhi said a more effective strategy would be to record the sex of a foetus at the outset of the pregnancy and then monitor its progress.

"My personal view is for a change in the present policy. Every pregnant woman should be compulsorily told whether it is a boy or girl," Gandhi said in the city of Jaipur.

"When a woman becomes pregnant that should be registered and that way you will be able to monitor right until the end whether she gave birth or not and what happened."

Parents and doctors can be jailed for up to five years for asking for or conducting a pre-natal sex test but they are still thought to be widespread.

Prime Minister Narendra Modi has implored his country to stop killing unborn girls, warning that its gender imbalance would have serious consequences.

A 2011 study in the British medical journal The Lancet found that up to 12 million girls had been aborted in the last three decades in India.

India had 940 women for every 1,000 men, according to the last official census published in 2011, up from 933 in 2001 in a trend that some campaigners say vindicates the current policy of banning sex tests.