Short birth-to-pregnancy intervals among African-born black women in Washington State

Abstract

Background: Short birth-to-pregnancy intervals have been associated with adverse perinatal outcomes. Racial disparities in short birth-to-pregnancy intervals and adverse perinatal outcomes are also well known. However, little is known about birth-to-pregnancy intervals among African-born black women in the US and risk factors that contribute to short birth-to-pregnancy intervals in this population.Objectives: To investigate the risk and associated risk factors of short birth-to-pregnancy intervals among African-born black women in Washington State.Study design: A retrospective cohort study using data from linked birth certificate and hospital discharge records for 18,984 consecutive, singleton birth pairs (1992–2013) to African-born black (n = 3312), US-born white (n = 7839), and US-born black women (n = 7833) in Washington State. Logistic regression models were used to determine adjusted odds ratios (aOR) and 95% confidence intervals (CI).Results: Women with short birth-to-pregnancy intervals (<6 months) comprised 10.0% of African-born women, 4.3% of US-born white women, and 6.8% of US-born black women. African-born black women had 3-fold (aOR 3.44; 95%CI: 2.53–4.68) and 1.5-fold (aOR 1.49; 95%CI: 1.28–1.74) higher risk of short birth-to-pregnancy intervals compared with US-born white women and US-born black women, respectively. Among African-born black women, those born in East Africa (aOR 3.17; 95%CI: 1.92, 5.24) had higher odds of short birth-to-pregnancy intervals compared with those born in other regions of Africa. Maternal age ≥35 years old (aOR 0.59; 95%CI: 0.35, 0.98), multiparity (aOR 0.73; 95%CI: 0.54–0.98), > 12 years education (aOR 0.52; 95%CI: 0.38–0.71), and cesarean delivery in prior births (aOR 0.61; 95%CI: 0.44–0.84) were associated with lower odds of short birth-to-pregnancy intervals among African-born black women.Conclusions: African-born black women have higher risk for short birth-to-pregnancy intervals compared with US-born white and black women. Several risk factors (age, parity, education, and prior delivery type) contribute to short birth-to-pregnancy intervals among African-born black women. Future studies may inform our understanding of factors affecting pregnancy spacing and family planning strategies among African-born black women.