565: The association between maternal weight gain and neonatal mortality

weight gain and neonatal mortality Joel Larma Ohio State University, Division of Maternal Fetal Medicine, Department of Obstetrics & Gynecology, Columbus, OH OBJECTIVE: To determine the association between maternal weight gain in pregnancy and neonatal mortality using a large population based birth registry. STUDY DESIGN: This is a population based retrospective cohort study of all births between 37 and 42 weeks gestation using the National Health Center for Vital Statistics 2005 Linked Birth/Infant Death Cohort Data Set. The primary outcome was neonatal mortality and the primary predictor was maternal weight gain. Maternal weight gain was categorized as less than 10 pounds, 10-24 pounds, 25-35 pounds and greater than 35 pounds. The referent group for the regression analysis were individuals with 25-35 pounds of weight gain during pregnancy. Initial univariate analysis was performed using Chi-square or Fishers exact tests for categorical variables and the t-test or MannWhitney U test for continuous variables. A multiple logistic regression model was performed using predictor variables that were found to alter the primary OR by 10-15%. Goodness of fit was assessed using the Hosmer-Lemeshow test. All analyses were performed using STATA 11.0. RESULTS: There were 4,145,887 births included in the final analysis with 27,968 cases of infant mortality which corresponds to a neonatal mortality rate of 6.69 cases per 1000 births. The following variables were found to be confounding variables and were included as covariates in the final analysis: maternal race, paternal race, number of prenatal visits and marital status. The adjusted odds ratio (aOR) for neonatal mortality for those who gained 10-24 pounds (relative to those who gained 25-35 pounds) was 1.87 (95% CI 1.11, 1.27). The aOR for neonatal mortality for those who gained 10 pounds was 1.5 (1.23, 1.47) and the aOR for those who gained greater than 35 pounds was 0.99 (0.93, 1.05. The Hosmer-Lemeshow test was nonsignificant indicating goodness of fit. CONCLUSION: There is a significantly increased odds of neonatal mortality among mothers with poor maternal weight gain who delivered a term infant, even after controlling for potential confounding variables. 566 Battle of the sexes: does gender exert a protective effect on neonatal mortality? Joel Larma Ohio State University, Division of Maternal Fetal Medicine, Department of Obstetrics & Gynecology, Columbus, OH OBJECTIVE: To determine the relationship between male gender and neonatal mortality using a large population based birth registry. STUDY DESIGN: This is a population based retrospective cohort study of all births between 23 and 42 weeks gestation using the National Health Center for Vital Statistics 2005 Linked Birth/Infant Death Cohort Data Set. The primary outcome was neonatal mortality and the primary predictor was male gender. The referent group for the regression analysis was female gender. Initial univariate analysis was performed using Chi-square or Fishers exact tests for categorical variables and the t-test or Mann-Whitney U test when appropriate. A multiple logistic regression model was performed using predictor variables that were either chosen a priori or were found to alter the primary OR by 10-15%. Goodness of fit was assessed using the Hosmer-Lemeshow test. All analyses were performed using STATA 11.0. RESULTS: There were 4,145,887 births included in the final analysis with 27,968 cases of infant mortality (6.69 cases per 1000 births). Among these, there were 2,122,872 males (51.20%) and 2,023,015 females born (48.80%) with 10,918 (57.07%) neonatal deaths among males and 8,212 (42.93%) neonatal deaths among females. The neonatal mortality rate for males was 6.00 per 1000 births and was 4.73 per 1000 births for females. The following variables were found to be significant confounders and were included in the final model: maternal age, marital status, tobacco use, congenital anomalies, birthweight, maternal weight gain, number of prenatal visits, low 5 minute Apgar and gestational age. The adjusted odds ratio (aOR) for neonatal death among males relative to females was 1.30 (1.25, 1.36) after controlling for potential confounding variables. The Hosmer-Lemeshow test was nonsignificant indicating goodness of fit. CONCLUSION: There is a significantly increased odds of neonatal mortality among male infants relative to female infants even after controlling for potential confounding variables. www.AJOG.org Epidemiology, Infectious Disease, Intrapartum Fetal Assessment, Operative Obstetrics, Obstetric Quality & Safety, Public Health-Global Health PosterSessionIV