NEW DELHI: Some Indian laws promote a preference for sons over daughters, the United Nations said on Thursday in a report that highlights the country's struggle to reverse a long-term decline in the number of girls.

Bans on child marriage, pre-natal sex selection tests and dowries are poorly enforced, while laws excluding daughters and widows from inheriting land still exist, a study by the UN World Population Fund (UNFPA) found.

“This study is significant because it holds up a mirror tothe laws that overtly or covertly fail to address discriminationor promote it,” Lise Grande, UN Resident Coordinator in India,told activists and reporters at the launch in New Delhi.

India has skewed child sex ratios that rights campaigners describe as alarming.

The number of girls under six years old has fallen for the past 50 years and there are now 919 girls to every 1,000 boys, against 976 in 1961, according the 2011 census.

Experts say a strong preference for sons is the root cause behind the uneven ratios, with some parents taking illegal gender tests to abort female foetuses.

Twelve million Indian girls have been aborted in the last three decades, a 2011 study in the British medical journal Lancet found.

Other girls die due to preventable diseases such aspneumonia and diarrhea, because they are sidelined in favour oftheir male siblings when it comes to access to health care andnutrition.

Kirti Singh, a lawyer and author of the UN study entitled ”The Law and Son Preference in India: A Reality Check”, said alack of political will meant many gender laws are not enforced.

Others, she said, are blatantly discriminatory and encourage the view that a male child is more valuable.

“There is, for example, the Goa polygamy law which actually permits a second marriage for the husband when there is no son from the first marriage,” Singh told the Thomson Reuters Foundation, referring to the coastal Indian state.

“There are also laws in some states which do not allow daughters and widows to inherit land.” Singh said this lowered the status of Indian females and legislation not only needed to be strictly implemented but also amended.

New laws, she said, were required to criminalise marital rape and so-called “honour killings”.

According to the latest UN Gender Equality Index, India has one of the worst gender differentials in child mortality of any country, ranking 132 out of 148 nations, worse than Pakistan and Bangladesh.

In much of India, a preference for male children is built into cultural ideology.

Sons are traditionally viewed as the breadwinners who will carry on the family name and perform the last rites of the parents - an important ritual in many faiths.

Girls are often seen as a burden that parents can ill afford, largely due to the hefty dowry of cash and gold jewelry that is required to marry them off.