LAUSR

STUDY DESIGN: This is a secondary analysis of a prospective, multicenter, observational study that included women with prior CD (MFMU Cesarean Registry). Two groups of patients from the registry were studied: patients with MAP and patients with placenta previa regardless of MAP (PP). The exposure of interest was the number of prior CD: 2 CD compared to 1 CD. The primary outcome was PTD <34 weeks. Secondary outcomes included transfusion of blood products, preterm labor requiring hospitalization/tocolysis, NICU admission, and a composite of maternal and neonatal complications. Balance of maternal demographics in the two groups was assessed using two sample t-tests and chisquare tests, and potential confounders were included in multivariable logistic regression models. Backward selection was used to identify parsimonious models. RESULTS: The MAP analysis included 194 women, 97 (50%) of whom had 1 prior CD and 97 (50%) of whom had 2 prior CD. There was no increased risk of PTD <34 weeks in women with 2 prior CD in the setting of MAP (23.7% vs. 29.9%, p1⁄40.27). Only need for plasma transfusion was associated with 2 prior CD (29.9% vs. 17.5%, p1⁄40.04) (Table 1). There were 776 women with PP, 667 (86%) with 1 prior CD and 109 (14%) with 2 prior CD. Similarly, there was no increased risk of PTD <34 weeks with 2 CD in the setting of PP (27.5% vs. 22.6%, p1⁄40.08). However, it was associated with a higher odds of need for transfusion and the maternal composite outcome (Table 2). CONCLUSION: Women with MAP or PP who have had 2 prior CD did not appear to have a higher risk of complications or PTD<34 weeks. Those with 2 prior CD may have a higher risk of maternal complications including need for transfusion products that may be independent of timing of delivery.