645: Electronic fetal monitoring in the United States: temporal trends in neonatal mortality and morbidity

Abstract

temporal trends in neonatal mortality and morbidity Cande V. Ananth, Suneet P. Chauhan, Han-Yang Chen, Mary E. D’Alton, Anthony M. Vintzileos Columbia University Medical Center, Department of Obstetrics and Gynecology, New York, NY, East Virginia Medical School, Department of Obstetrics and Gynecology, Norfolk, VA, Center for Urban Population Health, Department of Biostatistics, Milwaukee, WI, Winthrop University Hospital, Department of Obstetrics and Gynecology, Mineola, NY OBJECTIVE: The use of electronic fetal monitoring (EFM) has remained one of the fundamental screening tools to ensure fetal wellbeing in contemporary obstetrics. Despite its wide-spread utilization, whether EFM has helped reduce neonatal morbidity and mortality remains equivocal. We examine temporal trends in the utilization of EFM in the US, and quantify the extent to which such trends are associated with the decline in neonatal mortality and morbidity. STUDY DESIGN: We designed a retrospective cohort study of over 55 million non-anomalous singleton live births (24-44 weeks) delivered in the US between 1990 and 2004 to examine trends in EFM utilization. Changes in the risks of early and late neonatal mortality, cesarean and operative delivery for non-reassuring (NR) fetal status, Apgar score 4 at 5 min, and neonatal seizures at 34 weeks were examined in relation to changes in EFM utilization. Log-Binomial regression models were used to estimate risk ratios (RR) and 95% confidence intervals (CI) following adjustment for confounders. RESULTS: Utilization of EFM increased from 73.4% in 1990 to 85.7% in 2004 a relative increase of 17% (Fig). This EFM increase was associated with an additional 5% and 3% decline in early and late neonatal deaths, respectively, at 24-33 weeks, as well as a 3-7% additional decline in the 5-minute Apgar score 4 at 24-33, 34-36 and 37-44 weeks gestation. Increasing EFM use was also associated with 2-4% incremental increased rate of cesarean delivery for NR-fetal status, and a 3-4% operative delivery for NR-fetal status at 24-33, 34-36 and 37-44 weeks gestation. Increasing EFM was virtually not associated with any incremental changes in the rate of neonatal seizures. CONCLUSION: The temporal increase in EFM utilization in the US appears to be moderately associated with the recent declines in neonatal mortality, especially at preterm gestational ages, and increases in cesarean and operative deliveries for non-reassuring fetal status. This study adds a new dimension to well-known benefits of EFM. 646 Obstetrical interventions among nulliparous women in the United States, 2005-07 Cande V. Ananth, Allen J. Wilcox, Cynthia Gyamfi-Bannerman Columbia University Medical Center, Department of Obstetrics and Gynecology, New York, NY, National Institute of Environmental Health Sciences, Epidemiology Branch, Research Triangle Park, NC OBJECTIVE: Maternal or fetal compromise warrants urgent obstetrical intervention (labor induction, cesarean delivery), while reasons for elective deliveries may be less obvious. We characterize maternal profiles associated with elective and indicated deliveries, and contrast neonatal mortality in these two groups with that of spontaneous deliveries. STUDY DESIGN: This study was based on 1.7 million singleton live births delivered at 24-44 weeks to nulliparous US women in 2005-07. Three groups were characterized: indicated, elective, and spontaneous deliveries. Indicated deliveries included cesarean or labor induction for small for gestational age ( 3 percentile), non-reassuring fetal status, or gestational hypertension/preeclampsia. At 37 weeks, iatrogenic deliveries for women with chronic hypertension, pregestational or gestational diabetes were also considered indicated, as were breech presentations with delivery at 39 weeks. Pre-labor cesareans were considered elective. Women not classified as having an elective or indicated delivery were assigned to the spontaneous delivery group. RESULTS: 49% of births were classified as spontaneous delivery, 16% as indicated and 36% as elective. The proportion of births with elective deliveries increased sharply with advancing gestational age (Fig). Compared with spontaneous deliveries, women with either indicated or elective deliveries were less likely to deliver on weekend days. Women with elective deliveries were more likely to be older, educated, married, white, and non-smokers. The risk of neonatal mortality was consistently higher at every gestation week among elective compared to spontaneous deliveries. CONCLUSION: This study suggests that women with elective deliveries are at a socio-economic advantage compared with women undergoing spontaneous births, and elective and indicated deliveries are more likely on weekdays. Elective interventions are associated with increased neonatal mortality. The latter observation underscores the need for careful evaluation of risks and benefits when considering elective interventions. www.AJOG.org Epidemiology, Infectious Disease, Intrapartum Fetal Assessment, Operative Obstetrics, Obstetric Quality & Safety, Public Health-Global Health PosterSessionIV