Reproductive outcomes among Canadian-born and immigrant women with infertility in Ontario: a population-based cohort study

Study question —: Do reproductive outcomes, including live birth rates, differ between Canadian-born women and immigrant women with infertility in Ontario, Canada?

Summary answer — Immigrant women with infertility, particularly refugees, had lower probabilities of live birth within 2 years of diagnosis compared with Canadian-born counterparts.

What is known already — Immigrant populations experience barriers to fertility care, yet population-level data on reproductive outcomes among immigrant women diagnosed with infertility are limited.

Study design, size, duration — This population-based retrospective cohort study used linked administrative and registry data from ICES (formerly the Institute for Clinical Evaluative Sciences) Ontario between 2010 and 2019, with follow-up through 2021. The cohort comprised 254 463 women aged 18-55 years with a new physician-diagnosed infertility visit (OHIP 628), including 177 289 Canadian-born (69.7%) women, 66 131 non-refugee immigrants (26.0%), and 11 043 refugee immigrants (4.3%).

Participants/materials, setting, methods — Immigration status (Canadian-born, non-refugee immigrant, refugee immigrant) was derived from Immigration, Refugees and Citizenship Canada (IRCC-PR) data. The primary outcome was live birth within 2 years of infertility diagnosis. Secondary outcomes included time-to-pregnancy and birth by assisted conception. Relative risks were estimated using log-binomial regression and fecundability odds ratios (FORs) using discrete-time Cox models, adjusting for age, parity, income quintile, rurality, chronic conditions, and index year. Analyses followed the STROBE reporting guidelines.

Main results and the role of chance — Among 177 289 Canadian-born, 66 131 non-refugee immigrant, and 11 043 refugee immigrant women, live birth within 2 years occurred in 68 394 (38.5%) Canadian-born women, 22 363 (33.8%) non-refugees, and 3525 (31.9%) refugees, with aRRs of 0.96 (95% CI 0.94-0.97) and 0.90 (95% CI 0.87-0.94), respectively, compared to the Canadian-born cohort. The median time-to-pregnancy was 10 months (IQR 4-23) for Canadian-born women and 11 months (IQR 4-24) for immigrants, with reduced fecundability among both non-refugee (aFOR 0.97, 95% CI 0.96-0.99) and refugee immigrants (aFOR 0.89, 95% CI 0.86-0.91). Among those who achieved pregnancy, births by assisted conception occurred in 21 449 (24.5%) Canadian-born women, 5174 (17.6%) non-refugees, and 666 (14.4%) refugees, with adjusted RRs of 0.73 (95% CI 0.70-0.75) and 0.64 (95% CI 0.60-0.69), respectively, compared to the Canadian-born cohort.

Limitations, reasons for caution — Administrative data capture physician-diagnosed infertility, which may under-represent immigrants who are less likely to receive a diagnosis, leading to potential selection bias and underestimation of disparities. Residual confounding and incomplete ascertainment of conception type or social determinants remain possible.

Wider implications of the findings — Despite universal health coverage and a publicly funded IVF program, inequities in fertility outcomes persist for immigrants, especially refugees. These findings underscore the need for equity-focused fertility policy that addresses cultural acceptability, diagnostic access, and integration of mental-health supports in reproductive care.