(279) Migration and severe maternal outcomes in high income countries: a systematic review and meta-analysis

To assess migrants' risk of severe maternal outcomes compared to native women in high income countries overall, according to host country, and by the migrant’s region of birth.

Study Design:

Systematic literature review and meta-analysis using MEDLINE/Pubmed and EMBASE databases between 1990 and 25 March, 2022. Observational studies comparing the risk of maternal mortality or all-cause or cause-specific severe maternal morbidity in high income countries between migrant, defined by birth outside the host country, and native women, were included. Case-control and case studies were excluded. We used the Newcastle–Ottawa scale tool to assess risk of bias and performed random-effects meta-analyses when possible. Subgroup analyses were planned by host country and migrant’s region of birth.

Results:

From 2010 unique references, 36 studies reporting data from 32 databases in Europe, Australia, United States of America, and Canada were included. In Europe, migrants had a higher risk of maternal mortality than native women (pooled RR 1.36; 95%CI 1.13-1.64), but not in United States of America and Australia. Some subgroups of migrants, including those born in sub-Saharan Africa (pooled RR 3.33; 95%CI 2.52-4.40), Latin America and the Caribbean (pooled RR 2.82; 95%CI 1.15-6.93), and Asia (pooled RR 1.77, 95%CI 1.31-2.39) were at higher risk of maternal mortality than natives, but not those born in Europe or the Middle East and North Africa. Although studied less often and with heterogeneous definitions, patterns were similar for all-cause severe maternal morbidity and maternal intensive care unit admission.

Conclusion:

The differential risk of severe maternal outcomes in migrant versus native women in high income countries varies by host country and women’s region of origin. Our findings provide insight into the mechanisms of these inequalities. Harmonized definitions for all-cause and cause-specific severe maternal morbidity are needed to facilitate relevant syntheses of the available evidence regarding these inequalities in the future, in order to guide policies and care.