A new study hints that some families of Indian and South Korean origin in Ontario may be practising sex selection to ensure they have boy babies.

The study shows that the ratio of boy births to girl births is higher than average among those two communities, at least among babies born to women who’ve already had one child.

Normally in Canada there are 105 boys born for every 100 girls.

But the study, published in this week’s issue of the Canadian Medical Association Journal, shows that in women who came to Ontario from South Korea and who had a second child, 120 boys are born for every 100 girls.

For mothers who came to Canada from India, there are 111 boys for every 100 girls among second children, and 136 boys for every 100 girls among third children.

Dr. Joel Ray, the lead author of the study, says the figures are suggestive but this type of study can’t definitely say that sex selection is behind those elevated rates of boy babies.

That’s because of some limitations of the study. For one thing, Ray’s group doesn’t have information about the gender of the first child in all these families. Nor do they have evidence to explain the differences. Ray cautioned people shouldn’t make assumptions about his findings.

“We would strongly discourage people from drawing conclusions. Those conclusions are really presumptuous,” he said in an interview.

“Medical science and other forms of science have often drawn conclusions about a whole bunch of different things that when you complete the picture you end up realizing the conclusions were premature and wrong.”

Ray said he’s currently working on a follow-up study, looking at data on spontaneous and elective abortions in Ontario. That carefully anonymized data set shows the number and gender of children previously born to women undergoing abortions and is broken down by the women’s ethnic background as well.

The suggestion that women from some immigrant groups are selectively aborting female fetuses because they favour boy babies is a hot button topic.

Earlier this year the then acting editor of the Canadian Medical Association Journal, Dr. Rajendra Kale sparked a heated debate with an editorial he wrote suggesting sex selection is being practised by some Canadians of Asian descent.

He suggested groups that govern doctors across the country should adopt policies whereby women would not be informed of the sex of their fetus before 30 weeks gestation, to foil the practice.