549: Routine antepartum testing in women of advanced maternal age

of advanced maternal age Rachel Pilliod, Sarah Little, Aaron Caughey, Chloe Zera Brigham & Women’s Hospital, Obstetrics & Gynecology, Boston, MA, Brigham & Women’s Hospital, Obstetrics & Gynecology, Division of Maternal Fetal Medicine, Boston, MA, Oregon Health & Science University, Obstetrics & Gynecology, Portland, OR OBJECTIVE: Women of advanced maternal age (AMA) are at higher risk of poor obstetrical outcomes, including stillbirth and increased risk of cesarean section. Our study investigates the outcomes and costs of weekly antepartum testing for these women. STUDY DESIGN: A cost effectiveness model was created to compare routine antepartum testing starting at 36-40 weeks of gestation to expectant management in a hypothetical study population of women with advanced maternal age (AMA) who were otherwise low risk nulliparas with vertex, singleton gestations stratified by age groups of 35-39 and 40. Women not delivered by 41 weeks of gestation were induced. We accounted for an increased likelihood of cesarean delivery amongst AMA women. Baseline assumptions included a weekly IUFD risk of 0.068% with a relative risk of 1.73 and 2.33 for women 35-39 and 40 respectively. We assumed that antepartum testing was 70% sensitive and 90% specific. The cost-effectiveness threshold was set to $100,000 per QALY. Base-case and one-way sensitivity analysis of model parameters were performed. RESULTS: For AMA women between 35-39 and AMA women 40, weekly antepartum testing beginning at 36 weeks of gestation was cost-effective at $16,103 and $11,692 per quality-adjusted life-year (QALY) as compared to no antenatal testing. Two hundred and one women between 35-39 and 150 women 40 would need to be treated to prevent one stillbirth leading to 40 and 30 additional inductions of labor respectively. CONCLUSION: In our decision analytic model, we find that routine antepartum testing for AMA, but otherwise low risk women beginning at 36 weeks of gestation is cost-effective and leads to improved clinical outcomes. 550 Prenatal detection of structural cardiac defects and presence of associated anomalies: a prospective study of 1244 fetal echocardiograms Sinead Farrell, Aoife McTiernan, Colin Walsh, Colin McMahon, David Coleman, Orla Franklin, Cecilia Mulcahy, Shane Higgins, Peter McParland, Rhona Mahony, Stephen Carroll, Fionnuala McAuliffe University College Dublin, Dept of Obstetrics and Gynaecology, School of Medicine and Medical Science, Dublin, Ireland, National Maternity Hospital, Department of Fetal Medicine, Dublin, Ireland, Our Lady’s Children’s Hospital Crumlin, Department of Cardiology, Dublin, Ireland OBJECTIVE: To document detection of fetal cardiac defects in relation to (i) the indication for referral for fetal echocardiography, (ii) presence of associated extra-cardiac anomalies and (iii) karyotypic abnormalities. STUDY DESIGN: This is a prospective study from 2007-2011 inclusive. Data were recorded for fetal echocardiography and analysed for referral indication, the presence of extra-cardiac anomalies and invasive testing. RESULTS: During the five year period 1244 echocardiographs were recorded, 242 (19.5%) of which had a structural cardiac defect, table 1. The most common defects were AVSD (n 36), VSD (n 26), transpositions (n 15), tetralogy (n 15), hypoplastic left heart (n 27), coarctation (n 6) and valvular defects (n 30). Abnormal anatomy scan was the best indicator for detecting the presence of cardiac defects, compared to all other indications (p 0.0001). Invasive testing was performed for 44% of those identified with a cardiac anomaly, of which 54 (51%) were abnormal karyotypes including 48 trisomies, 5 microdeletions and one triploidy. Thirty-seven percent (n 89) of those with a cardiac anomaly also had an extra-cardiac defect, including ventriculomegaly, omphalocele, duodenal atresia, and cleft lip/ palate. In addition these fetuses were significantly more likely to have a karyotypic abnormality when compared with those with an isolated cardiac anomaly (p 0.0001). CONCLUSION: This study suggests most congenital cardiac defects occur in a low risk population, highlighting the importance of the 20week anomaly scan for detection of cardiac and other defects prenatally. Significant numbers of chromosomal and extra-cardiac defects in this study emphasize the importance of thorough evaluation of any fetus identified with a cardiac defect.