Lower Rates of Preterm Birth in Women of Arab Ancestry: An Epidemiologic Paradox—Michigan, 1993–2002

Abstract

Preterm birth (PTB), <37 weeks gestation, occurs in 12.1% of live births annually and is associated with significant morbidity and mortality in the United States. Racial/ethnic subgroups are disproportionately affected by PTB. Michigan is home to one of the largest Arab-American communities in the country; however, little is known about PTB in this population. This study examined the maternal demographic profile and risk factors of preterm birth (PTB) among foreign-born and US-born women of Arab ancestry relative to US-born Whites in Michigan. Using Michigan Vital Statistics data, we examined correlates of PTB for primiparous U.S.-born white (n = 205,749), U.S.-born Arab (n=1,697), and foreign-born Arab (n=5,997) women who had had a live-born singleton infant during 1993-2002. We examined variables commonly reported to be associated with PTB, including mother's age and education; insurance type; marital status of parents; receipt of prenatal care; mother's chronic hypertension, diabetes, and tobacco use; and infant sex. Foreign-born Arabs are less educated and more likely to be on Medicaid, and they receive less prenatal care than US-born Whites. Prevalence of PTB was 8.5, 8.0, and 7.5% for US-born Whites, US-born Arabs, and foreign-born Arabs, respectively. Pregnancy-related hypertension was the only predictor of PTB that these three groups had in common: Adjusted Odds Ratio (AOR)=2.1 (95% Confidence Interval (CI)=1.99, 2.21), AOR=2.6 (95% CI=1.24, 5.51), and AOR=2.6 (95% CI=1.55, 4.31) for US-born whites, US-born Arabs, and foreign-born Arabs, respectively. Foreign-born Arab women in Michigan have a higher-risk maternal demographic profile than that of their US-born white counterparts; however, their prevalence of PTB is lower, which is consistent with the epidemiologic paradox reported among foreign-born Hispanic women.