RESULTS: Of the 1798 women randomized, we excluded 13 multifetalbirths leaving 1785 for analysis: 1491 had an epidural and 294 did not.Of those with epidural, 8.0% had clinical chorioamnionitis comparedwith only 1.0% without epidural: unadjusted OR�8.3 (95% CI: 2.6-26); p�0.0001. After multivariable logistic regression, epidural use(adjusted OR 6.3; 1.9-21), multiparity (0.43; 0.32-0.59) and pre-eclampsia (0.44; 0.21-0.91) were significantly associated with chorio-amnionitis (Table). In additional analyses (Table) we adjusted furtherfor duration of labor (a potential reason for the association with epi-dural and a proxy for number of vaginal exams).CONCLUSION: Epidural use is strongly associated with an increase inthe clinical diagnosis of chorioamnionitis independently of labor du-ration and likely due to epidural fever. Multiparity and preeclampsiaare protective.

279 The impact of delivery timing on cesarean deliveryrisk in women with mild destational diabetesAmelia Sutton1

1For the Eunice Kennedy Shriver National Institute of Child Healthand Human Development Maternal-Fetal Medicine UnitsNetwork, Obstetrics and Gynecology, Bethesda, MDOBJECTIVE: To evaluate the relationship between gestational age (GA)at delivery and the risk of cesarean delivery (CD) in women with mildgestational diabetes (GDM).STUDY DESIGN: This is a secondary analysis of a multi-center RCT ofmild GDM treatment. Women delivering at term (� or equal to 37weeks) were stratified by delivery GA in completed weeks, and deliv-ery mode. CD risk was evaluated using two complementary methods:1) induction of labor (IOL) vs. spontaneous labor: women induced ateach GA compared with those who spontaneously labored and deliv-ered at the same GA (outcome at each week compared with 39 weekreferent), and 2) IOL vs. expectant management: women deliveredafter IOL at each GA compared with those who delivering after spon-taneous labor at the same GA or subsequently after spontaneous orinduced labor (outcome at each week compared with expectant man-agement at that week). Additionally, a composite perinatal outcome(stillbirth, neonatal death, hypoglycemia, hyperbilirubinemia, ele-vated cord-blood C-peptide level, or birth trauma) was evaluated.Logistic regression adjusted for maternal age, parity, ethnicity, BMI,smoking, ultrasound �20 weeks, SGA and GDM treatment group.RESULTS: Among 679 eligible women, the CD rate was 13%. Rates ofCD and crude OR (95% CI), according to GA relative to 39 weeks(method 1), and comparing IOL by GA vs. expectant management(method 2), are presented in the Table. The perinatal composite didnot vary significantly by GA using either analysis method. Multivari-able logistic regression revealed similar findings.CONCLUSION: In pregnancies complicated by mild GDM at term, therisk of CD increases with increasing GA. Delivery before 40 weeks may

reduce CD risk. Labor induction is associated with a 2-4.5 fold in-crease in CD, but only at or after 40 weeks.

280 Transversus abdominal plane (TAP) block foranalgesia after cesarean section reduces narcoticuse in the 24-48 hour postoperative time frameSamit Patel1, Brad M. Dolinsky1, Jennifer Gotkin2, RaywinHuang3, Charles Darling4, Peter Napolitano1

1Madigan Army Medical Center, Obstetrics and Gynecology, Tacoma, WA,2Madigan Army Medical Center, Obstetrics and Gynecology, Olympia, WA,3Madigan Army Medical Center, Department of Clinical Investigation,Tacoma, WA, 4Madigan Army Medical Center, Anesthesia, Tacoma, WAOBJECTIVE: The Transversus Abdominal Plane (TAP) block involvesultrasound guided placement of a peripheral nerve block of the ab-dominal wall immediately after surgery. Our objective was to comparethe narcotic requirements, between 24-48 hours, in both scheduledand non-scheduled postoperative cesarean patients in those who havereceived the TAP block verses intrathecal or intravenous narcotics.STUDY DESIGN: Retrospective cohort study of 50 women who receiveda TAP block for postoperative analgesia after cesarean. One hundredcontrols without a TAP block were matched by parity, indication forcesarean, and BMI. The primary outcome was the total number ofnarcotic tablets 24-48 hours after delivery. Independent t-test and theAnalysis of covariance were employed to determine significant differ-ences (��0.05) between cohorts, adjusting for potential confoundersthat were not matched.RESULTS: The TAP block cohort had a significantly lower number oftotal narcotics than the control cohort (�3.80.5, p�0.001), a reduc-tion of 30%. Even after adjusting for covariates, there was a significantreduction in the total narcotic dose (34% p�.0001) compared to con-trols, mean tablets 6.4 �/�SEM .460, 95% CI (5.5,7.3) vs 9.7�/�SEM .306, 95% CI (9.1,10.3) respectively. In a subgroup analysisof labored women, there was a 41% reduction of dose for the TAPblock cohort ( 5.5 �/�SEM .850, 95% CI (3.8,7,2)) vs 9.2 �/�SEM.553, 95% CI (8.1,10.3), p�.002.CONCLUSION: The TAP block is associated with decreased narcotic us-age 24-48 hours following surgery compared to traditional analgesia.Further randomized studies on relevant patient populations are indi-cated

www.AJOG.org Diabetes, Labor, Medical-Surgical-Disease, Obstetric Quality & Safety, Prematurity, Ultrasound-Imaging Poster Session II

Supplement to JANUARY 2012 American Journal of Obstetrics & Gynecology S135