But many mothers want boys not girls, and the Indian Medical Association says the law is almost impossible to uphold.

The law is almost impossible to enforce

In some sections of Indian society, having daughters is less acceptable than having sons.

Dr V Parameshvara, a former president of the Indian Medical Association, says intrinsically women have a lower status in India than men.

He says girls can bring economic and social burdens to a family, and rather than bring children into the world to be ill-treated by a patriarchal society, expectant mothers prefer to abort their female babies.

The proportion of females to males in India has been going down since the beginning of the 20th century, with up to 50m fewer women in the population than expected.

In recent years, the ratio has dropped dramatically.

Dr Parameshvara says there has been a long-standing tradition in some circles of killing girl babies just after birth.

But because technology now allows mothers to know the sex of their child before it is born, terminations have become widespread.

Dr Parameshvara claims that a law introduced specifically to prevent abortions because of the sex of the unborn child is being ignored throughout the country.

The Indian Medical Association is urging international colleagues at the World Medical Association to support a campaign against female feticide and female infanticide to rid India of what it calls "this social evil".