In her new book "Unnatural Selection," Science writer Mara Hvistendahl examines how the trend toward choosing boys over girls through sex-selective abortions has spread through the developing world, particularly in Asia. Coining the term "Generation XY," Hvistendahl provides the grim results of sex selection: while the natural sex ratio at birth is 105 boys born for every 100 girls, in India the figure has risen to 112 boys and in China, 121. The Chinese city of Lianyungang actually recorded 163 boys per 100 girls in 2007.

The shortage of women is already giving rise to deep societal problems. New markets have been created for women in Asia, including wedding agencies that arrange marriages between South Korean men and women often from poorer nearby countries like Vietnam, that now account for 11% of all marriages in South Korea. There is also a growing practice of child marriage in China, where wealthier families buy young girls to secure wives for their sons early. And with so many surplus men (e.g., up to a fifth of men will be single in northwestern India by 2020), she suggests that the excess testosterone could lead to raised levels of crime and violence.

But what distinguishes Hvistendahl's book from other similar reports is that, as the Guardian notes in a profile today, she "lays the blame squarely on western governments and businesses that have exported technology and pro-abortion practices without considering the consequences," unlike other accounts, that solely basing sex selection on cultural practices.

Amniocentesis and ultrasound scans have had largely positive applications in the west, where they have been used to detect fetal abnormalities. But exported to Asia and eastern Europe they have been intricately linked to an explosion of sex selection and a mushrooming of female abortions. Hvistendahl claims western governments actively promoted abortion and sex selection in the developing world, encouraging the liberalization of abortion laws and subsidizing sales of ultrasounds as a form of population control.

"It took millions of dollars in funding from US organizations for sex determination and abortion to catch on in the developing world," she writes.

Moreover, she also blames the UNFPA, the UN's main population agency, for refusing to own up to its role in funding sex-selection.

In 1979 China signed a $50m four-year deal with a UN body designed to help it control its spiralling population through family planning. It was the largest foreign aid package Beijing had accepted in almost 20 years. But the funds became entwined in China's one-child policy that was just taking hold, and instead of sponsoring an education drive for small families, the money was used to pay for posters in Chinese villages proclaiming "You can abort it! But you cannot give birth to it."

"The effects of the major UN agency tasked with population advocacy distancing itself from the issue of sex selective abortion are immense," she writes, noting that the agency's foot-dragging has discouraged other global funds from engaging with the crisis.

On the other hand, Richard Dawkins at BoingBoing takes on Hvistendahl's thesis, arguing that Western science and governments are not culpable for making sex selection possible and prevalent -- and the fault remains in cultural practices. He notes that in the past, cultures with a lower value for women "might have fostered selective infanticide of newborn girls." Now "scientific culture makes it possible to know the sex of a fetus, say by amniocentesis or ultrasound scanning." To that he asks, "Why do we blame science for offering a method to do bad things?"

He argues further that "sex selection, in societies that value sexual equality, could have beneficial effects on curbing overpopulation," in that it "could help provide parents with exactly the family balance they want." The factors that brought about the XY generation may better "be blamed on the cultural and religious practices that despise and discriminate against women in the first place."