Sex ratios at birth among Indian immigrant subgroups according to time spent in Canada

Objectives — To examine whether son-biased male to female (M:F) ratios at birth among linguistically different subgroups of Indian immigrants vary according to duration of residence in Canada.

Methods — We analyzed a retrospective cohort of 46 834 live births to Indian-born mothers who gave birth in Canada between 1993 and 2014. The M:F ratio at birth was calculated according to the sex of previous live births and stratified by (1) time since immigration to Canada (<10 and ≥10 years) and (2) mother tongue (Punjabi, Gujarati, Hindi, and other). We estimated adjusted odds ratios (aORs) using multivariate logistic regression to assess the probability of having a male newborn with 5-year increases in duration of residence in Canada for each language group. ORs were adjusted for married status, knowledge of English/French, maternal education at arrival and age and neighborhood income at delivery.

Results — Among all Indian immigrant women with two previous daughters, M:F ratios were higher than expected (1.92, 95% CI 1.73 to 2.12), particularly among those whose mother tongue was Punjabi (n = 25 287) (2.40, 95% CI 2.11 to 2.72) and Hindi (n = 7752) (1.63, 95% CI 1.05 to 2.52). M:F ratios did not diminish with longer duration in Canada (Punjabi 5-year aOR 1.03, 95% CI 0.81 to 1.31; Hindi 5-year aOR 0.94, 95% CI 0.42 to 2.17).

Conclusion — Among the Punjabi and Hindi women with two previous daughters, longer duration of residence did not attenuate son-biased M:F ratios at the third birth. Gender equity promotion may focus on Punjabi- and Hindi-speaking Indian immigrant women regardless of how long they have lived in Canada.