376: Midtrimester placental location and obstetric outcome

Abstract

ObjectiveTo determine whether low placentation in the midtrimester is an independent risk factor for postpartum hemorrhage.Study DesignA retrospective cohort study was conducted of women undergoing transvaginal ultrasonography between 18 0/7 and 23 6/7 weeks gestation. Subjects with low placentation, defined as a placental edge ≤2.5 cm from the cervical os, were included. They were subdivided into three groups: low-lying placenta (LLP - 0.1 to 2.5 cm), marginal previa (MP - touching but not overlapping the os), and complete previa (CP - covering the os). A group of randomly identified control subjects with normal placentation was selected for comparison. Maternal demographic characteristics, follow-up ultrasound data, and delivery data were recorded. Resolution was defined as a follow-up ultrasound that demonstrated the placental edge to be >2.5cm from the cervical os.ResultsFour hundred and ten women with low placentation were identified during the period of study. Resolution rates for LLP, MP and CP were 98.6%, 89.1% and 59.1% respectively. Compared to controls, subjects with midtrimester low placentation had increased rates of postpartum hemorrhage and uterotonic use. In multivariable analysis, these increased risks continued to be present even among women in whom the low placentation resolved (OR 2.81, CI 1.51-5.24, and OR 2.30, CI 1.30-4.06, respectively).ConclusionWomen with a midtrimester diagnosis of low placentation remain at risk for postpartum hemorrhage despite high rates of resolution. ObjectiveTo determine whether low placentation in the midtrimester is an independent risk factor for postpartum hemorrhage. To determine whether low placentation in the midtrimester is an independent risk factor for postpartum hemorrhage. Study DesignA retrospective cohort study was conducted of women undergoing transvaginal ultrasonography between 18 0/7 and 23 6/7 weeks gestation. Subjects with low placentation, defined as a placental edge ≤2.5 cm from the cervical os, were included. They were subdivided into three groups: low-lying placenta (LLP - 0.1 to 2.5 cm), marginal previa (MP - touching but not overlapping the os), and complete previa (CP - covering the os). A group of randomly identified control subjects with normal placentation was selected for comparison. Maternal demographic characteristics, follow-up ultrasound data, and delivery data were recorded. Resolution was defined as a follow-up ultrasound that demonstrated the placental edge to be >2.5cm from the cervical os. A retrospective cohort study was conducted of women undergoing transvaginal ultrasonography between 18 0/7 and 23 6/7 weeks gestation. Subjects with low placentation, defined as a placental edge ≤2.5 cm from the cervical os, were included. They were subdivided into three groups: low-lying placenta (LLP - 0.1 to 2.5 cm), marginal previa (MP - touching but not overlapping the os), and complete previa (CP - covering the os). A group of randomly identified control subjects with normal placentation was selected for comparison. Maternal demographic characteristics, follow-up ultrasound data, and delivery data were recorded. Resolution was defined as a follow-up ultrasound that demonstrated the placental edge to be >2.5cm from the cervical os. ResultsFour hundred and ten women with low placentation were identified during the period of study. Resolution rates for LLP, MP and CP were 98.6%, 89.1% and 59.1% respectively. Compared to controls, subjects with midtrimester low placentation had increased rates of postpartum hemorrhage and uterotonic use. In multivariable analysis, these increased risks continued to be present even among women in whom the low placentation resolved (OR 2.81, CI 1.51-5.24, and OR 2.30, CI 1.30-4.06, respectively). Four hundred and ten women with low placentation were identified during the period of study. Resolution rates for LLP, MP and CP were 98.6%, 89.1% and 59.1% respectively. Compared to controls, subjects with midtrimester low placentation had increased rates of postpartum hemorrhage and uterotonic use. In multivariable analysis, these increased risks continued to be present even among women in whom the low placentation resolved (OR 2.81, CI 1.51-5.24, and OR 2.30, CI 1.30-4.06, respectively). ConclusionWomen with a midtrimester diagnosis of low placentation remain at risk for postpartum hemorrhage despite high rates of resolution. Women with a midtrimester diagnosis of low placentation remain at risk for postpartum hemorrhage despite high rates of resolution.