Being a refugee or having a refugee status? Birthweight and gestational age outcomes among offspring of immigrant mothers in Sweden

Abstract

Aims: to evaluate whether the information on refugee status based on the residence permit is a useful source of information for perinatal health surveillance. Methods: Using the Swedish population registers (1997-2012), we use multinomial regression models to assess the associations between migration status (refugee and non-refugee) and birth outcomes derived from birthweight and gestational age: low birthweight (LBW) (<2500 g), macrosomia (≥4000 g); preterm: (<37 w) and post-term (≥42 w). The Swedish-born population was used as a reference group. Results: Compared to the Swedish-born population, an increased OR (odds ratio) of LBW and post-term was found among migrants with and without refugee status (respectively: OR for refugees: 1.47 [95% CI: 1.33-1.63] and non-refugees:1.27 [95% CI: 1.18-1.38], for refugees: 1.41 [95% CI: 1.35-1.49] and non-refugees:1.04 [95% CI: 1.00-1.08]) with statistically significant differences between these two migrant categories. However, when looking at specific regions of origin, few regions show differences by refugee status. Compared to Swedes, lower or equal ORs of preterm and macrosomia are observed regardless of migratory status. Conclusions: Small or no differences were observed in birth outcomes among offspring of women coming from the same origin with different migratory status, compared to their Swedish counterparts. This suggests that information on migration status is not a relevant piece of information to identify immigrant women at higher risk of experiencing adverse reproductive outcomes. Our results however might be explained by the large proportion of women coming to Sweden for family reunification who are classified as non-refugee migrants.