Millions of sex-selective abortions in India have skewed gender ratios, and the origins of the problem can be traced to American-supported population control strategies decades ago, a U.S. congressional panel heard Tuesday.

Republican Rep. Chris Smith, a staunch opponent of abortion, took up the issue at the House subcommittee on global health and human rights at a hearing titled, "India's Missing Girls."

The panel has often been a forum for tough criticism of China's one-child policy. Its chair, Smith, was more nuanced in his comments on India, acknowledging that Prime Minister Manmohan has decried the falling proportion of girls in his country. But Smith railed against what he called the systematic "extermination" of female fetuses and authorities' failure to enforce laws against it. He said that has led to a dearth of women which has fueled as men seek marriage partners.

The Indian Embassy in Washington did not immediately respond to a request for comment Tuesday.

India's has grown even as the country has witnessed strong economic growth. The 2011 census showed 914 girls for every 1,000 boys younger than 6. That was a drop from 927 girls for every 1,000 boys a decade previously.

Experts say such ratios are the result of abortions of female fetuses, or sheer neglect leading to a higher death rate among girls. Part of the reason Indians favor sons is the enormous expense of marrying off girls.

Sabu George, a researcher and member of India's Campaign Against Sex Selection, said that over the last decade, more than 6 million female fetuses were eliminated before birth in India. He predicted that the numbers will rise in the coming decade unless there was a more determined effort to enforce existing legislation, which he said is currently only being implemented in the wealthiest state of Maharashtra, where the proportion of girls is even lower than the national average.

Republican Rep. Thomas Marino said that if the national government really wanted the law to be implemented, "they could have an enormous amount of influence over it, instead of saying the problem is with the states."

Matthew Connelly, a history professor at Columbia University in New York, said it was Western development professionals focused on controlling global population growth in the 1960s who first promoted sex-selective abortion. He recounted how the U.S.-based Population Council instructed Indian doctors in how to determine the sex of a fetus, and publicly advocated sex-selective abortions, which began to be done systematically in India by the late 1970s.

"It is precisely because the U.S. took a leading role in advocating population control worldwide that we cannot pretend that we have no responsibility for the consequences," Connelly said in testimony.

Speaking ahead of the hearing, Connelly said that international organizations engaged in family planning are nowadays motivated by ideals of reproductive rights and health, but there's lingering suspicion of public health programs in countries such as India because of what happened in the past.

Mallika Dutt, from the rights group Breakthrough, defended the rights of Indian women to have access to legal abortions.

She had a testy engage with Republican Rep. Randy Weber who pressed her on whether that constituted a "human right."

"Given the many ways in which women are controlled and exploited and abused it's very important for women to have full control over their own reproduction," she said.

Many Republican lawmakers in the U.S. Congress are strong opponents of abortion. Smith is in the vanguard, and said Tuesday he wants to ensure that U.S. development agencies don't support coercive . He's also raised questions about the use of ultrasound equipment from U.S. companies for purposes in India.

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