The effects of CenteringPregnancy on maternal and infant health outcomes: a moderation analysis.

BACKGROUND:CenteringPregnancy (CP) has been expected to produce beneficial outcomes for women and their infants. However, previous studies paid little attention to testing variations in CP's effects across women from different demographic groups. This study aimed to test how multiple demographic factors (obesity, race, ethnicity, marital status and socioeconomic status) moderate CP's effects on health outcomes. METHODS:This study employed a quasi-experimental design. De-identified hospital birth data were collected from 216 CP participants and 1159 non-CP participants. We estimated the average treatment effect of CP on outcome variables as a baseline. Then we estimated the average marginal effect of CP by adding each of the moderating variables in regression adjustment models. RESULTS:CP produced salutary effects among those who were obese or overweight and unmarried as well as women with lower socioeconomic status. These salutary effects were also strengthened as maternal age increased. However, CP was ineffective for Hispanic/Latinx women. CONCLUSIONS:CP produced more beneficial health outcomes for high-risk women such as obese, unmarried women and those with lower socioeconomic status. These are meaningful findings from a public health perspective.