128: The interaction between preeclampsia and race-ethnicity as a factor in the preterm delivery of twin gestations

Abstract

and race-ethnicity as a factor in the preterm delivery of twin gestations Judith Chung, Yvonne W. Cheng, Jonathan M. Snowden, Rachel Pilliod, Amy E. Doss, Aaron Caughey University of California, Irvine, Obstetrics and Gynecology, Orange, CA, University of California, San Francisco, Department of Obstetrics, Gynecology, and Reproductive Sciences, San Francisco, CA, Oregon Health Sciences, Obstetrics and Gynecology, Portland, OR, Oregon Health and Science University, Department of Obstetrics and Gynecology, Portland, OR OBJECTIVE: Multiple gestations and African-American women have been shown to have an increased risk of preeclampsia. The purpose of this investigation was to evaluate the incidence of preeclampsia among twin gestations delivering prior to 37 weeks gestation and to evaluate the interaction between preeclampsia and racial-ethnic group in this preterm population. STUDY DESIGN: This is a retrospective cohort study of twin gestations delivered at 24 0/7-36 6/7 weeks gestation in the state of California during the year 2006. Using logistic regression, odds ratios (OR) and 95% confidence intervals (CI) for preeclampsia were then determined as a function of gestational age at delivery, divided into three categories: 24-27, 28-31, 32-37 weeks. For each gestational age category, the impact of racial-ethnic group on the odds of preeclampsia were then evaluated. RESULTS: The highest odds of preeclampsia was seen among twin gestations delivered between 32-37 weeks (aOR, 1.75; 95% CI, 1.571.95), while there was a reduced odds of preeclampsia among twins delivering between 24-27 weeks (aOR, 0.74; 95% CI, 0.61-0.90) and 28-32 weeks (aOR, 0.42; 95% CI, 0.27-0.65). Racial-ethnic differences in the odds of preeclampsia were most apparent among deliveries at 32-37 weeks, with the highest odds seen among Caucasian women (aOR, 1.19; 95% CI, 0.78-1.83). African-American women delivering at any of the preterm gestations did not have an increased odds of preeclampsia. CONCLUSION: Preeclampsia appears to be a significant contributor to the preterm delivery twin pregnancies only at the later preterm gestations (32-37 weeks). While African-Americans may have an overall higher incidence of the disease, Caucasian women with twin pregnancies, who require delivery at these later preterm gestations, seem to have the highest burden of disease. Preeclampsia is reduced among all race-ethnic groups if delivery occurs at before 32 weeks. 129 Obstetrical outcomes in patients with low-lying placenta in the second trimester Justin Bohrer, William Goh, Cori-Ann Hirai, James Davis, Ivica Zalud University of Hawaii John A Burns School of Medicine, Obstetrics, Gynecology & Women’s Health, Honolulu, HI, University of Hawaii John A Burns School of Medicine, Clinical Research Center, Honolulu, HI OBJECTIVE: The objective of our study was to determine if women with a history of a low-lying placenta (LLP) in the second trimester have increased blood loss at delivery. STUDY DESIGN: IRB exemption was obtained. A total of 178 electronic charts were reviewed of patients referred for an ultrasound examination at a single institution between January 2009 and February 2011. 89 patients with a LLP on ultrasound between 16 and 22 weeks gestation were compared with 89 time-matched controls. A placenta was designated low-lying if its edge was within 2 cm proximity to the internal cervical os on transvaginal ultrasound. Data was analyzed using JMP (SAS Institute Inc, Cary, NC). RESULTS: Of the 89 patients in the LLP cohort, all but one resolved on repeat ultrasound in the third trimester. Age (OR 1.07, 95% CI 1.021.13) and history of dilation and curettage procedures (OR 1.55, 95% CI 1.04-2.45) were indentified as risk factors for LLP using univariate analysis. Gravity, parity, ethnicity, smoking status, number of prior cesarean deliveries, and uterine surgeries were similar between groups. Age remained the only independent predictor of LLP after controlling for potential confounders (adj OR 1.07, 95% CI 1.021.13). Mean change in hemoglobin following delivery in the LLP cohort ( 1.56 g/dL, SD 1.13) was greater than that in the control group (1.22 g/dL, SD 0.94, p .0358). Mean change in hemoglobin remained significantly different between groups after excluding the patient with persistent LLP and controlling for differences in parity and mode of delivery (p .0098). 6 patients (6.7%, 95% CI 3.1-13.9%) with LLP required inpatient admission for antepartum bleeding compared with 0 (0%, 95% CI .02-4.0%) admissions in the control group (p .029). Birthweight, incidence of preterm birth, umbilical artery pH, estimated blood loss, incidence of postpartum hemorrhage, mode of delivery, and gestational age at delivery were similar between groups. CONCLUSION: Patients with a LLP in the second trimester are at increased risk for antepartum admissions for bleeding and have increased blood loss at the time of delivery.