RT Journal Article SR Electronic T1 Revisiting instrumental vaginal delivery rates in obese pregnant women JF Archives of Disease in Childhood - Fetal and Neonatal Edition JO Arch Dis Child Fetal Neonatal Ed FD BMJ Publishing Group Ltd and Royal College of Paediatrics and Child Health SP Fa88 OP Fa88 DO 10.1136/archdischild.2011.300162.44 VO 96 IS Suppl 1 A1 D Janga A1 M Parisaei A1 K Erskine YR 2011 UL http://fn.bmj.com/content/96/Suppl_1/Fa88.1.abstract AB Introduction Obesity is the greatest threat to the childbearing population of UK. According to the 2003–2005 CEMACH report, half of those who died were obese, 15% extremely obese. Materials and methods We performed a prospective study in our unit for a period of 4 months (February–May 2009), total deliveries during this period were 1560. The details were collected from 1235 (79.2% of the cases). To evaluate the prevalence of morbid obesity (body mass index (BMI) 35 or more) in our pregnant women and their obstetric outcome, we looked into the booking BMI and collected their demographic details. We compared the outcomes in the group with BMI less than 35 with the second group comprising of women with BMI 35 or more. Results The prevalence of obesity in our population was 212/1235 (18%), and 8% (n=88) had BMI of 35 or more. The median BMI was 38. Preeclampsia was significantly higher in the obese pregnant women (0.5% vs 10.2%, p= 0.049). Increased incidence of augmentation with oxytocin, post-partum haemorrhage and neonatal intensive care admission rates were noticed in the group with BMI>35. Caesarean section (CS) rates were higher in the obese group (emergency CS rates of 10.6% vs 19.3%, p=0.02 and elective CS rates 14% vs 21.6%, p=0.06). Interestingly the instrumental vaginal delivery rates were lower in the obese group (3.4% vs 11.4%, p=0.01). The rates of third degree tears and shoulder dystocia were not significantly different. Discussion This study showed that the women with greater BMI (>35), had an increased caesarean section rates, but lower instrumental delivery rates in contrast.