714: Adverse outcome in planned out-of-hospital births versus planned hospital births in Oregon

Abstract

versus planned hospital births in Oregon Jonathan Snowden, Janice Snynder, Stella Dantas, Lani Doser, Yvonne Cheng, Aaron Caughey Oregon Health and Science University, Department of Obstetrics & Gynecology, Portland, OR, Northwest Permanente PC, Physicians and Surgeons, Department of Obstetrics & Gynecology, Portland, OR, University of California, San Francisco, Department of Obstetrics & Gynecology, San Francisco, CA OBJECTIVE: While recent research has been able to delineate planned home birth from accidental home birth in the US, there remain challenges to delineating planned hospital births from births occurring in the hospital after transfer. We compared perinatal outcomes between planned home births and planned hospital births in Oregon. STUDY DESIGN: This study was a retrospective cohort study of all births occurring in Oregon between 2008 and 2010, using vital statistics data. In 2008 the Oregon birth certificate began collecting data on hospital transfers, allowing identification of intended hospital births. We calculated the prevalence of several adverse outcomes (including neonatal death and low Apgar scores) in planned home births and planned hospital births, using multiple hospital comparison groups. Hospital comparison groups A and B excluded hospital transfers to get at intended hospital birth; Comparison group A was further limited to births meeting eligibility criteria for home birth in Oregon (e.g, gestational age 35 or greater, no preeclampsia, etc). The conventional hospital comparison group (group C, frequently employed due to data limitations) was all hospital births regardless of transfer status. RESULTS: When comparing planned home birth to the appropriate hospital comparison group (A), the rate of neonatal death was lower in hospital births (0.08% versus 0.26%, P 0.002), as was the rate of 5-minute Apgar score 7. NICU admission was more common in planned hospital births in comparison group A (3.3% versus 0.7%; P 0.001). For all outcomes studied, rates were higher in hospital comparison groups B and C, reflecting the higher risk profile of hospital transfers and other high-risk births excluded from comparison group A. CONCLUSION: It is now acknowledged that studying the relative safety of birth locale requires analysis of planned home birth; similarly, it is important to compare these outcomes to intended hospital births, where prevalence of adverse outcomes is much lower than in hospital births overall. 715 Development and validation of a risk factor scoring system for first-trimester prediction of pre-eclampsia Katherine Goetzinger, Methodius Tuuli, Alison Cahill, George Macones, Anthony Odibo Washington University in St. Louis, Obstetrics and Gynecology, St. Louis, MO OBJECTIVE: 1) To develop a risk-based scoring system for first-trimester prediction of pre-eclampsia (PEC) by combining maternal characteristics and first-trimester biomarkers of placental dysfunction and 2) to validate this scoring system in our patient population. STUDY DESIGN: This is a secondary analysis of a prospective cohort of 1200 patients presenting for aneuploidy screening between 11-14 weeks’ gestation. Maternal history was collected through questionnaire and medical record review. Maternal serum pregnancy-associated plasma protein A (PAPP-A) levels were measured by immunoassay and bilateral uterine artery (UA) Doppler studies performed. The primary outcome was PEC, defined as blood pressure 140/90 in the presence of proteinuria after 20 weeks’ gestation. Using the first half of the study population, a prediction model for PEC was created, and a weighted score was assigned to each risk factor based on the adjusted odds ratios from the model. Receiver-operating characteristic (ROC) curves and test performance characteristics were used to determine the optimal score for the prediction of PEC. The model was then validated in the second half of the study population by comparing test performance characteristics and area under the ROC curves (AUC). RESULTS: Significant risk factors and their weighted scores derived from the prediction model were chronic hypertension (4), history of PEC (3), pre-gestational diabetes (2), body mass index 30 kg/m (2), presence of bilateral UA notching (1), and PAPP-A multiples of the median 10th percentile (1). The AUC for the risk scoring system was 0.76 (95% CI 0.69-0.83), and the optimal threshold for predicting PEC was a total score of 6. This AUC did not differ significantly from the AUC observed in our validation cohort [AUC 0.78 (95% CI 0.690.86), p 0.75]. Test characteristics are shown in the Table. CONCLUSION: We present a reproducible risk-based scoring system for first-trimester prediction of PEC that may be useful in future intervention studies. Rates of labor induction among women without indications for IOL of varying body mass index in California, 2007