Association of white blood cell count after operative vaginal delivery with maternal adverse outcome: A retrospective cohort study.

Abstract

The white blood cell count is often used to assess the maternal condition after an operative vaginal delivery. However, it remains unknown whether the maternal white blood cell count on the day after delivery is associated with sequential maternal adverse outcomes, especially infectious complications. The aim of this study was to investigate the association between maternal white blood cell count on the day after operative vaginal delivery and sequential maternal adverse events. The study was a retrospective cohort study using the Medical Data Vision claims database containing administrative claims data, discharge abstracts, and laboratory values in Japan. We identified all patients who underwent operative vaginal delivery with data on maternal white blood cell count from December 2011 to November 2020. The main composite outcome was maternal adverse outcomes, comprising additional treatment for maternal injuries, postpartum intravenous antibiotic use, and intensive care unit use during hospitalization. We conducted a restricted cubic spline analysis to investigate the nonlinear association between white blood cell count and the primary outcome. There were 485 eligible patients including 73 patients with occurrence of the primary outcome. The median (interquartile range) white blood cell count on the day after delivery in all eligible women was 15,170 (12,610-18,300)/mL. In the restricted cubic spline analysis, there was no significant association of white blood cell count with the primary outcome. White blood cell count on the day after operative vaginal delivery was not significantly associated with maternal adverse outcomes during hospitalization.