Around 10 million female foetuses may have been aborted in India over the past two decades because of ultrasound sex screening and a traditional preference for boys, according to a study published online in The Lancet. Researchers based in Canada and India looked through data from a national survey, conducted among 1.1 million households in 1998, and at information about 133,738 births that took place in 1997.
They found that in cases where the preceding child was a girl, the gender ratio for a second birth was just 759 girls to 1,000 boys.
And when the two previous children were girls, this ratio fell even further, to 719 girls to 1,000 boys.
On the other hand, when the preceding child or children were male, the gender ratio among successive births was about the same.
Based on the natural sex ratio in other countries, around 13.6-13.8 million girls should have been born in India in 1997 -- but the actual number was 13.1 million.
"We conservatively estimate that prenatal sex determination and selective abortion accounts for 0.5 million missing girls yearly," said one of the authors, Prabhat Jha of St. Michael's Hospital at the University of Toronto, Canada.
"If this practice has been common for most of the past two decades since access to ultrasound became widespread, then a figure of 10 million missing female births would not be unreasonable."
The "girl deficit" is far more prominent in educated women, the investigators found.
The number of boys born as second children was twice as high among this group than among illiterate mothers.
However, the deficit did not vary by religion.
The study published by the London-based medical journal comes on the heels of a report last October by the United Nations Population Fund (UNFPA), which warned that infanticide or abortion was driving India towards a gender imbalance with alarming social consequences.
Afghanistan, China, Nepal, Pakistan and South Korea face similar problems, the UNFPA said.
