Socioeconomic impacts on the intergenerational associations of preterm birth.

Background: The impact of socioeconomic status on intergenerational associations of preterm birth (PTB) is poorly understood.

Objective: To estimate the socioeconomic status of intergenerational impact of PTB transmission.

Study design: This retrospective cohort study included all eligible singleton female infants born in Nebraska from 1995 to 2005 (n = 6631) and followed up from 2009 to 2019. Mothers' first singleton infants born 2009-2019 were linked to the mothers and included in the description and generalized estimating equations.

Results: Mothers born PTB were 37% more likely to have a PTB infant after controlling for maternal and grandmother's prenatal care adequacy, maternal residential poverty, pre-pregnancy diabetes, hypertension, C-section, and infants' gender. In poor neighborhoods, the adjusted preterm odds ratio of former born preterm mothers (compared with mother not born PTB) was 1.56 (95% confidence interval (CI): 1.02, 2.38). Moreover, moving from a poor neighborhood to a relatively well-off neighborhood was a protective factor for PTB with an adjusted odds ratio of 0.47 (95% CI: 0.23, 0.95).

Conclusions: Mothers born preterm were at increased risk of having PTB infants, especially in poor areas. Maternal upward social mobility was a protective factor for PTB recurrence.