Significantly more boys born to Indian mothers in Canada than to Canadian-born mothers

April 16, 2012

Mothers born in India but living in Canada are significantly more likely to have male babies for their second and third births compared with women in Canada, found a new study of male:female ratios in CMAJ (Canadian Medical Association Journal).

"Our findings raise questions about why there are more male liveborns than female liveborns among Indian who have had two or more previous babies," states Dr. Joel Ray, St. Michael's Hospital and University of Toronto.

Researchers from St. Michael's Hospital and the University of Toronto looked at all live births in Ontario — 766 688 births — between 2002 and 2007. They used the mother's country or region of birth to categorize each birth, with 486 599 from Canada, Europe (58 505), (31 978), China (23 818), rest of East Asia (18 971), Pakistan (18 018), South Korea (3663) and others. They calculated male:female by country or region and the number of previous deliveries the mother had at the current birth (0, 1, 2, 3 or more). They also looked at the country of birth for fathers.

For most women, the male:female ratio was 1.05, and the ratio did not change with increasing numbers of previous births. However, women from India and South Korea who had previous children were significantly more likely to give to males. For Indian-born women with more than one prior child, the male:female ratios were even more pronounced.

Previous research conducted in India and a study looking at Canadian census data for South Asian and East Asian immigrants show similar patterns of higher male: female ratios linked to increasing numbers of children, especially when the prior offspring were girls.

"Whether this difference in ratios was the result of prenatal sex selection should be determined by direct study of practices of sex-selected preimplantation and pregnancy termination among individuals from various world regions," conclude the authors. "In addition, an analysis of the duration of residence in Canada, access to fertility care, family income and parental preferences would be of value in describing factors that might influence prenatal sex selection."

The study was limited to singleton births and could not account for any sex selection in multiple pregnancies from fertility treatments. The researchers also could not determine the sex of older siblings born to the same mother.

CMAJ published an editorial on the topic of sex-selective abortions in Canada earlier this year.

Explore further: Ultrasounds worsen Asia women shortage: UN

More information: Online:

Related Stories

Ultrasounds worsen Asia women shortage: UN

October 6, 2011

Increased access to technology that allows parents to know the sex of their foetus has left Asia short of 117 million women, mostly in China and India, the UN said Thursday.

Female feticide in Canada requires action

January 16, 2012

Canada should prohibit disclosure of the sex of a fetus until after 30 weeks of pregnancy to combat female feticide which is practised by some ethnic groups in Canada and the United States, states an editorial in CMAJ (Canadian ...

Recommended for you

US hospital to offer uterus transplants

November 13, 2015

A leading US hospital said Thursday it is preparing to offer women uterine transplants, a technology that has been proven in Sweden and could help those struggling with infertility.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.