SMFM Abstracts S211
Volume 189, Number 6 Am J Obstet Gynecol 559
OCCIPUT POSTERIOR PRESENTATIONS ARE INCREASED IN FETAL BRAIN INJURY CORTNEY KIRKENDALL1, JEFFREY PHELAN1, 1Childbirth Injury Prevention Foundation, Pasadena, CA OBJECTIVE: To determine whether occiput posterior presentations among singleton term neonates with permanent brain injury are increased over neurologically normal controls. STUDY DESIGN: Singleton term neonates with permanent brain injury were identified (group 1) and compared with previously published neurologically normal controls (group 2 [BMJ 1998;317:1554]). Entry criteria for group 1 were a documented vertex presentation with a known orientation of the VTX in an occiput anterior (OA), transverse(OT), or posterior (OP) position during the delivery process. RESULTS: Of 423 cases of permanent brain injury, 394(93%) had a VTX presentation. Of these, the orientation of the VTX was known in 180 (46%)-OA106 (59%); OT-25 (14%); OP-47 (26%); Other-2 (1%). On comparison, group 1 cases were 9.13 more likely to have an OP presentation than group 2 cases (47/ 180 [26%] vs15/400 [3.8%] OR 9.1,95%CI [4.76,16.6] P, 0.000001). CONCLUSION: The current investigation corroborates previous reports that occiput posterior presentations are significantly increased among cases of fetal brain injury. The clinical significance of this observation will need to be investigated.
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UTERINE TACHYSYSTOLE AND HYPERSTIMULATION DURING INDUCTION OF LABOR MICHAEL BEBBINGTON1, LEO PEVZNER1, ESTHER SCHMUEL1, PETER BERNSTEIN1, ASHLESHA DAYAL1, JONATHAN BARNHARD1, CYNTHIA CHAZOTTE1, IRWIN MERKATZ1, 1Albert Einstein College of Medicine, Obstetrics & Gynecology and Women’s Health, Bronx, NY OBJECTIVE: To analyze the timing of tachysystole and hyperstimulation during induction of labor with misoprostol and dinoprostone. STUDY DESIGN: Patients enrolled in a randomized controlled trial comparing misoprostol with dinoprostone for induction of labor had fetal and uterine monitoring throughout their induction. Patients received either one dinoprostone 10-mg vaginal insert or misoprostol 50 lg pv every 4 hours for a maximum of 3 doses. Oxytocin was then started per protocol if the patient was not in active labor. After delivery, the computerized record was reviewed by a single individual not involved in the patient’s care and blinded to the patient’s treatment allocation. Standard definitions of tachysystole and hyperstimulation were used. Statistical analysis was performed using chi-square. RESULTS: 200 patients were randomized, with 98 allocated to misoprostol, and 102, to dinoprostone. A total of 67 patients experienced tachysystole, 40 in the misoprostol arm and 27 in the dinoprostone group (P = 0.05). There was no difference in the incidence of multiple tachysystole events between the groups (28 vs 17 P = 0.56). Among the patients receiving misoprostol, 23 events occurred after the first dose, 12 following the second and 5 after the third. The incidence of tachysystole after the initial 12 hours of treatment was 10% in the misoprostol group and 60% in the dinoprostone group. Hyperstimulation occurred in 12 patients receiving misoprostol compared to 15 patients receiving dinoprostone. Urgent delivery occurred in 3 patients in each group. These differences were not statistically significant. CONCLUSION: Misoprostol is associated with a significant increase in the frequency of tachysystole when compared to dinoprostone, with no increase in the rate of hyperstimulation or the need for urgent interventions.
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MISOPROSTOL VERSUS DINOPROSTONE FOR LABOR INDUCTION AT TERM: A RANDOMIZED CONTROLLED TRIAL MICHAEL BEBBINGTON1, ESTHER SCHMUEL1, LEO PEVZNER1, PETER BERNSTEIN1, ASHLESHA DAYAL1, JONATHAN BARNHARD1, CYNTHIA CHAZOTTE1, IRWIN MERKATZ1, 1Albert Einstein College of Medicine, Obstetrics & Gynecology and Women’s Health, Bronx, NY OBJECTIVE: To determine if intravaginal misoprostol is more effective than dinoprostone for the induction of labor. STUDY DESIGN: Between April 2001 and May 2003, women presenting for labor induction with a Bishop score #6 were enrolled. Women with SROM, prior uterine surgery, multiple gestation, and malpresentation were excluded. Patients were randomized to receive one 10-mg dinoprostone vaginal insert or misoprostol 50-lg tablet pv every 4 hours for a maximum of three doses. Oxytocin was then started per protocol if the patient was not in active labor. The primary outcome was the induction to delivery interval. Chi-square and t-test were used as appropriate. RESULTS: 200 patients were randomized, 98 to misoprostol and 102 to dinoprostone. The patients were comparable with respect to maternal age, parity, gestational age, indication for induction, and Bishop score. Both the interval to active labor (774.3 ± 52.1 min vs 1088.2 ± 76.8 min, P = 0.0009) and the induction-to-delivery interval (1053.1 ± 62.6 min vs 1456 ± 74.4 min, P < 0.0001) were shorter in the misoprostol arm. The number of patients requiring oxytocin augmentation (47 vs 76), the mean dose infused (6.5 ± 0.9 lg/min vs 13.0 ± 1.1 lg/min), and the duration of use (270.6 ± 38.5 min vs 572.5 ± 48.7 min) were lower with misoprostol (P < .0001). There were no differences in route of delivery, Apgar scores, or NICU admissions. Length of stay was shorter in the misoprostol group (P = 0.03). Although misoprostol use was associated with more tachysystole events (40 vs 27, P = 0.05), there was no difference in the incidence of hyperstimulation (P = 0.683). CONCLUSION: Misoprostol is a more effective labor induction agent than dinoprostone, with no increased maternal or neonatal morbidity.
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SHOULDER DYSTOCIA IS ASSOCIATED WITH PROTRACTED ACTIVE LABOR IN NULLIPAROUS WOMEN SHOBHA MEHTA1, EMILY HAMILTON2, EMMANUEL BUJOLD1, SUSAN BERMAN1, ROBERT SOKOL1, SEAN BLACKWELL1, 1Wayne State University, Obstetrics/Gynecology, Detroit, MI 2McGill University, Obstetrics & Gynecology, Montreal, Quebec OBJECTIVE: To evaluate the progression of the first stage of labor in pregnancies complicated by shoulder dystocia (SD). STUDY DESIGN: A computerized perinatal database was used to identify all nulliparous women with SD delivering at a single institution from 1997-2001. Controls were matched based on birth weight, induction, and race. Labor progress was quantified using a mathematical model that compared cervical dilations in the study group to a preexisting reference population, which was adjusted at each exam for parity and changing conditions, such as contraction frequency, epidural use, and cervical assessment at the previous examination. Statistical methods included paired t test, Wilcoxon rank sum, and chi-square. RESULTS: A total of 7904 nulliparous patients met inclusion criteria and delivered vaginally. Of these, 0.8% (65) had SD. Neurologic injury occurred in 27.7% (18/65), which was comparable to previously reported range of 4%-40%. There was no difference in mean dilation (2.4 vs 2.5), effacement (69.4% vs 69.3%) or station (2.6 vs 2.5) when patients with SD were compared to controls. Of note, overall labors were slow, with the mean percentile ranking of 30.0% vs 30.3%. The incidences of very slow labor, defined as the proportion of examinations under the 5th (18.8% vs 18.9%) or the 10th percentile (32.7% vs 35.8%) were similar. However, SD patients had a significantly lower mean percentile ranking at the last exam of the first stage (40.7% vs 55.6%, P = 0.012). CONCLUSION: With SD, there is a relative slowing of labor progression occurring late in the first stage that is not explained by differences in fetal weight, induction, epidural, or uterine contraction patterns. The degree of slowness is well within the limits of normal labor progression. It presages the previously described prolongation of the second stage (Mehta et al., CAOG, 2003).