Sex-selective abortions—that is, abortions performed because of the predicted sex of the fetus—occur most frequently where there is a strong gender bias that manifests in a preference for sons. Amniocentesis and sex determination tests have been used to inform parents of the sex of their unborn child. Such cases have resulted in the performing of an abortion when the baby was not of the sex wanted.
In India, over one million (approximately 3,000 a day) female foetuses are aborted each year after testing. In Bombay alone, 258 private centres for amniocentesis have sprung up over the past few years, and 16 government-supported clinics provide the service as well, where the abortion of female foetuses is as high as 99%. Portable ultrasound units have meant that in some areas the service is "more available than running water". It is estimated that between 1978 and 1982, there were over 78,000 cases of amniocentesis followed by abortion of females in India as a whole.