Sarah S Osmundson1, Amy E Wong, Susan E Gerber. 1. Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA. s.osmundson@gmail.com
Abstract
OBJECTIVES: The purpose of this study was to assess whether low placentation in the second trimester is an independent risk factor for postpartum hemorrhage. METHODS: A retrospective cohort study of women undergoing transvaginal sonography between 18 weeks' and 23 weeks 6 days' gestation was conducted. Patients were subdivided into three groups: low-lying placenta (0.1-2.5 cm), marginal previa (touching but not overlapping the os), and complete previa (covering the os). Low placentation was used as a descriptive for all cases (low-lying placenta, marginal previa, and complete previa) in this study. A group of randomly identified control patients with normal placentation was selected for comparison. RESULTS: During the period of study, 410 women with low placentation were identified. Compared to controls, patients with second-trimester low placentation had increased rates of postpartum hemorrhage and uterotonic use. These increased risks persisted even among women in whom the low placentation resolved (odds ratio, 2.72; 95% confidence interval, 1.46-5.07; odds ratio, 2.18; 95% confidence interval, 1.24-3.84). CONCLUSIONS: Women with a second-trimester diagnosis of low placentation are at increased risk of postpartum hemorrhage.
OBJECTIVES: The purpose of this study was to assess whether low placentation in the second trimester is an independent risk factor for postpartum hemorrhage. METHODS: A retrospective cohort study of women undergoing transvaginal sonography between 18 weeks' and 23 weeks 6 days' gestation was conducted. Patients were subdivided into three groups: low-lying placenta (0.1-2.5 cm), marginal previa (touching but not overlapping the os), and complete previa (covering the os). Low placentation was used as a descriptive for all cases (low-lying placenta, marginal previa, and complete previa) in this study. A group of randomly identified control patients with normal placentation was selected for comparison. RESULTS: During the period of study, 410 women with low placentation were identified. Compared to controls, patients with second-trimester low placentation had increased rates of postpartum hemorrhage and uterotonic use. These increased risks persisted even among women in whom the low placentation resolved (odds ratio, 2.72; 95% confidence interval, 1.46-5.07; odds ratio, 2.18; 95% confidence interval, 1.24-3.84). CONCLUSIONS:Women with a second-trimester diagnosis of low placentation are at increased risk of postpartum hemorrhage.