127: Advanced maternal age: what is the risk of stillbirth & infant death by each additional week of expectant management?

stillbirth & infant death by each additional week of expectant management? Jessica Page, Jonathan Snowden, Emily Griffin, Yvonne Cheng, Amy Doss, Melissa Rosenstein, Aaron Caughey Oregon Health and Science University, Obstetrics and Gynecology, Portland, OR, University of California, San Francisco, Obstetrics and Gynecology, San Francisco, CA OBJECTIVE: To determine the composite risk of stillbirth and infant death by week of gestation at term in advanced maternal age (AMA) pregnancies compared to pregnancies not complicated by AMA. STUDY DESIGN: A retrospective cohort study was conducted using 2005 National birth certificate data including AMA pregnancies. Term stillbirth by gestational age (GA) was calculated using a denominator of 10,000 ongoing pregnancies. Infant death was defined as mortality within the first year of life and was calculated per 10,000 deliveries at each GA. Advanced maternal age was defined as age 35 or greater. A composite mortality rate was used to estimate the risk of stillbirth by remaining pregnant for an additional week and infant death risk at the next week of gestation. Exclusion criteria included fetal anomalies and multiple gestations. RESULTS: The risk of stillbirth was higher in the AMA population by GA at term and interestingly, infant death rates were lower in AMA pregnancies throughout all term GAs. Composite risk of expectant management, defined as the ongoing risk of stillbirth during the additional week plus the risk of infant death at the following week, was higher at GAs 38wks in the AMA population, indicating that the risk of stillbirth exceeds that of infant death at these GAs. The point at which risk of expectant management surpassed that of infant death in the non-AMA population occurred at 39 wks GA, reflecting the increased risk of stillbirth in AMA pregnancies. CONCLUSION: The composite risk of expectant management of AMA pregnancies at term exceeds the infant mortality risk at 38 weeks due to the continuing increases in risk of stillbirth at later GAs. These risks should be taken into account when determining the optimal time of delivery for AMA pregnancies. 128 Opiate abuse/usage in pregnancy and newborn head circumference Kevin Visconti, Kerry Hennessy, Craig Towers, Mark Hennessy, Bobby Howard University of Tennessee Medical Center, Obstetrics & Gynecology, Maternal-Fetal Medicine, Knoxville, TN OBJECTIVE: To evaluate whether opiate abuse/usage in pregnancy affects newborn head circumference. Opiate abuse in pregnancy has significantly increased in our location and large dosages of strong oral agents (oxycodone, oxymorphone, and buprenorphine) are the primary drugs ingested. Most of the literature to date in pregnancy has evaluated heroin and methadone. STUDY DESIGN: All newborns admitted to the neonatal intensive care unit for treatment of neonatal abstinence syndrome were prospectively collected. The birth and perinatal ultrasound information were retrospectively obtained and analyzed. Data collected included the gestational age (GA) at delivery, gender, birthweight, head circumference (HC) at birth, the opiate type, and the perinatal ultrasound assessment of growth parameters prior to delivery. RESULTS: From January 1, 2010 to June 30, 2012, 323 neonates were admitted for the treatment of NAS. A total of 93 (28.8%) had a HC 10th percentile for GA (p 0.01) compared to controls. Of these 93, 25 (7.7%) were 3rd percentile and 68 (21.1%) were 3rd 10th percentile; however, 62.4% were AGA in birthweight at delivery. Of the 323 total cases, 196 (61%) had at least one ultrasound evaluation in the perinatal unit prior to delivery and of these, 141 were within 10 days of birth. Based on the ultrasound parameters, a HC 5th percentile was found in 38.4% of cases of which 73% were consistent with the post-delivery findings. Of interest, the femur length measurements were 5th percentile in 36.3% of fetuses in these 141 ultrasound evaluations; however, 69.4% were AGA for birthweight at delivery. Risk of stillbirth, infant death & expectant management by week of gestational age at Term in AMA pregnancies www.AJOG.org Clinical Obstetrics, Epidemiology, Fetus, Medical-Surgical Complications, Neonatology, Physiology/Endocrinology, Prematurity Poster Session I