OBJECTIVE: To identify characteristics of pregnant women potentially influencing the decision to participate in peripartum interventional research.

METHODS: Women screened as eligible to participate in two prospective interventional trials conducted in the labor and delivery unit at a single center were included. Characteristics of eligible women were compared based on their decision whether to participate or not. The best predictors of research participation were identified using multivariable logistic regression analyses.

RESULTS: Of the 605 subjects who screened as eligible to participate, 363 (60%) agreed to participate and 242 (40%) declined. Women using a private obstetric provider or who had prior obstetrical complications were less likely to participate [aOR 0.6 (95% CI: 0.4-0.8)] and [aOR 0.6 (95% CI: 0.4-0.9)], respectively. A history of a mental health condition and a higher body mass index (BMI) were marginally more likely to participate [aOR 1.5 (95% CI: 1.0-2.3)] and [aOR 1.03 (95% CI: 1.0-1.1)], respectively. Overall logistic regression model R(2) was 0.23.

CONCLUSIONS: There are differences between eligible subjects who decide to participate or not participate in prospective peripartum interventional research. There is a need to better understand non-participation in order to improve recruitment of representative populations that allow more generalizable research results.