Maternal Socioeconomic Mobility and Preterm Delivery: A Latent Class Analysis.

Objective Growing evidence suggests that maternal socioeconomic mobility (SM) is associated with pregnancy outcomes. Our study investigated the association between maternal SM from childhood to adulthood and the risk of preterm delivery (PTD), and examined heterogeneity of associations by race/ethnicity. Methods In this study, 3019 pregnant women enrolled from 5 Michigan communities at 16-27 weeks' gestation (1998-2004) provided their parents' socioeconomic position (SEP) indicators (education, occupation, receipt of public assistance) and their own and child's father's SEP indicators (education, occupation, Medicaid status, and household income) at the time of enrollment. Latent class analysis was used to identify latent classes of childhood SEP indicators, adulthood SEP indicators, and SM from childhood to adulthood, respectively. A model-based approach to latent class analysis with distal outcome assessed relations between latent class and PTD, overall and within race/ethnicity groups. Results Three latent classes (low, middle, high) were identified for childhood SEP indicators and adulthood SEP indicators, respectively; while four latent classes (static low, upward, downward, and static high) best described SM. Women with upward SM had decreased odds of PTD (Odds ratio = 0.60, 95% confidence interval: 0.42, 0.87), compared to those with static low SEP. This SM advantage was true for all women and most pronounced in white/others women. Conclusions Maternal experiences of upward SM may be important considerations when assessing PTD risk. Our results support the argument that policies and programs aimed at improving women's SEP could lower PTD rates.