title: Variations in gestational length and preterm delivery by race, ethnicity and migration.
abstract: Preterm delivery rates within industrialized countries have been reported to vary according to the parents' race, ethnicity and migrant status; however, such disparities are poorly understood. In this paper, the available evidence and potential clinical significance of racial/ethnic and migrant disparities in gestational length and preterm delivery are assessed alongside potential explanatory factors. Although measurement bias in gestational length has the potential to inflate disparities, there is a consistently higher risk of preterm birth among some racial/ethnic groups. These differences most likely reflect lasting socio-economic disadvantage and discrimination rather than genetic mechanisms. The effect of migrant status is less conclusive due to heterogeneity of populations and the healthy migrant effect; however, environmental influences in the receiving country are implicated in driving increases of overall preterm rates. When assessing preterm delivery rates across ethnic and migrant groups, the use of standardized, ultrasound-based pregnancy dating methods is crucial to minimize bias. Current evidence does not justify the provision of a different clinical care approach to minority or immigrant women solely based on their race, ethnicity or country of origin; however, these labels may serve as flags for further inquiry on individual risk factors and a detailed obstetric history.
authors.affiliation: Norwegian Advisory Unit on Women's Health, Women and Children's Division, Oslo University Hospital, PO Box 4950, Nydalen, 0424 Oslo, Norway. Electronic address: isorbye@ous-hf.no.
authors.forename: Ingvil K
authors.initials: IK
authors.lastname: Sørbye
authors.affiliation: Centre for Research on Inner City Health, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada.
authors.forename: Susitha
authors.initials: S
authors.lastname: Wanigaratne
authors.affiliation: Centre for Research on Inner City Health, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada; Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada.
authors.forename: Marcelo L
authors.initials: ML
authors.lastname: Urquia
mesh_terms: D019049:Developed Countries; D003906:Developing Countries; D054242:Emigrants and Immigrants; D005006:Ethnicity; D005060:Europe / Q000453:epidemiology; D005260:Female; D005865:Gestational Age; D054624:Health Status Disparities; D054625:Healthcare Disparities / Q000208:ethnology; D006801:Humans; D007231:Infant, Newborn; D008913:Minority Groups; D011247:Pregnancy; D047928:Premature Birth / Q000208:ethnology*; D044469:Racial Groups; D012307:Risk Factors; D012959:Socioeconomic Factors
keywords: ethnicity; gestational length; migration; minority groups; preterm delivery; race