Centering and Racial Disparities (CRADLE study): rationale and design of a randomized controlled trial of centeringpregnancy and birth outcomes

Liwei Chen, Amy H. Crockett, Sarah Covington-Kolb, Emily Heberlein, Lu Zhang, Xiaoqian Sun

In the United States, preterm birth (PTB) before 37 weeks gestational age occurs at an unacceptably high rate, and large racial disparities persist. To date, medical and public health interventions have achieved limited success in reducing rates of PTB. Innovative changes in healthcare delivery are needed to improve pregnancy outcomes. One such model is CenteringPregnancy group prenatal care (GPNC), in which individual physical assessments are combined with facilitated group education and social support. Most existing studies in the literature on GPNC are observational. Although the results are promising, they are not powered to detect differences in PTB, do not address the racial disparity in PTB, and do not include measures of hypothesized mediators that are theoretically based and validated. The aims of this randomized controlled trial (RCT) are to compare birth outcomes as well as maternal behavioral and psychosocial outcomes by race among pregnant women who participate in GPNC to their counterparts in individual prenatal care (IPNC) and to investigate whether improving women's behavioral and psychosocial outcomes will explain the potential benefits of GPNC on birth outcomes and racial disparities. This is a single site RCT study at Greenville Health System in South Carolina. Women are eligible if they are between 14-45 years old and enter prenatal care before 20 6/7 weeks of gestational age. Eligible, consenting women will be randomized 1:1 into GPNC group or IPNC group, stratified by race. Women allocated to GPNC will attend 2-h group prenatal care sessions according to the standard curriculum provided by the Centering Healthcare Institute, with other women due to deliver in the same month. Women allocated to IPNC will attend standard, traditional individual prenatal care according to standard clinical guidelines. Patients in both groups will be followed up until 12 weeks postpartum. Findings from this project will provide rigorous scientific evidence on the role of GPNC in reducing the rate of PTB, and specifically in reducing racial disparities in PTB. Establishing the improved effect of GPNC on pregnancy and birth outcomes can change the way healthcare is delivered, particularly with populations with higher rates of PTB. NCT02640638 Date Registered: 12/20/2015.