Effect of Group Prenatal Care Attendance on Gestational Diabetes Mellitus and Preterm Birth.

INTRODUCTION Adequate prenatal care is an important tool for achieving optimal health outcomes for both mothers and their babies. A low group prenatal care (GPNC) attendance rate may influence clinical outcomes. We aimed to estimate the effect of GPNC attendance on the risk of gestational diabetes (GDM) and preterm birth (PTB).

METHODS This is a prospective study that included pregnant individuals (N = 1089) enrolled in the GPNC arm of the Cradle RCT from February 2016 to March 2020. We performed multivariable logistic regressions to estimate the effect of GPNC sessions on PTB or GDM adjusting for potential confounders.

RESULTS Each additional GPNC session attended was associated with a 9% reduction in the risk of PTB (95% CI, 4%-14%) and 1 fewer (95% CI, 0-2) PTB cases per 100 pregnant individuals. Similarly, each additional GPNC session attended was associated with an 11% reduction in the risk of GDM (95% CI, 4%-17%) or 1 fewer (95% CI, 0-2) GDM cases per 100 pregnant individuals. The risk reduction was even higher when attending ≥ 5 GPNC versus < GPNC: adjusted risk ratio [aRR] 0.54: 95% CI (0.36, 0.82) for PTB; aRR: 0.41, 95% CI (0.24, 0.71) for GDM.

CONCLUSIONS Attending more GPNC sessions could lead to a reduction in the risk of PTB and GDM, with an increasing amount of GPNC visits associated with even more risk reduction in PTB and GDM. The relationship between attending prenatal care as a group and mitigation of adverse pregnancy outcome risk is complex and warrants further study.

TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT02640638.