Families in India are increasingly aborting their second child if they know it to be a girl and they already have a daughter, a study shows. Scientists estimate that up to 6 million girls have been aborted in India over the past decade by couples who do not want a large family and are determined to have a son. The practice is more widespread among wealthier and better educated Indian families, who are better able to afford the prenatal tests and medical intervention they want. While it has been known that there has been a tendency to abort girls in India since the first census in 1871, the latest evidence suggests that the practice is common throughout the country. The research, published in the Lancet , suggests that the Indian government's attempt to tackle the issue by outlawing ultrasound scans that identify the sex of a foetus has not worked. The Pre-Natal Diagnostic Techniques Act was passed in 1996 to stop medical staff telling parents the sex of a foetus.