Maternal education and adverse birth outcomes among immigrant women to the United States from Eastern Europe: a test of the healthy migrant hypothesis.

Immigrant women to the U.S. often have more favorable birth outcomes than their native-born counterparts, including lower rates of preterm birth and low birth weight, a phenomenon commonly attributed to a healthy migrant effect. However, this effect varies by ethnicity and country of origin. No previous study has examined birth outcomes among immigrants from the post-Communist countries of Eastern Europe, a group which includes both economic migrants and conflict refugees. Using data on 253,363 singletons births from New York City during 1995-2003 we examined the risk of preterm birth (PTB) (<37 weeks) or delivering a term small-for-gestational-age (SGA) infant among immigrants from Russia and Ukraine (RU), Poland, and former Yugoslavia Republics (FYR) relative to US-born non-Hispanic whites (NHW). Women in all three Eastern European groups had significantly later entry into prenatal care, were more likely to be Medicaid recipients, and had lower educational attainment than US-born NHW. In binomial regression analyses adjusting for age, education, parity, and pre-pregnancy weight, women from RU and FYR had lower risk of PTB than US-born NHW, whereas women from Poland had similar risk. Lower SGA risk was found among women from Poland and FYR, but not RU. When stratified by education, women with <12 years of education from all Eastern European groups had a reduced risk of PTB relative to US-born NHW. An educational gradient in PTB and SGA risk was less pronounced in all Eastern European groups compared to US-born NHW. The healthy migrant effect is present among immigrants from Eastern Europe to the U.S., especially among women with less education and those from the former Yugoslavia, a group that included many conflict refugees.