Amniotic fluid levels of phospholipase A2 in fetal rats with retinoic acid induced myelomeningocele: the potential "second hit" in neurologic damage.

OBJECTIVES: There is growing evidence of ongoing, in utero neurological damage in fetuses with myelomeningocele (MMC). Phospholipase A2 (PLA2) has known neurotoxic properties and is predominantly present in its secretory isoform (sPLA2) in meconium, the passage of which is increased in MMC fetuses. The objective of this study was to determine if amniotic fluid (AF) levels of PLA2 are elevated in a rat model of MMC. METHODS: Timed pregnant Sprague-Dawley rats were gavage fed 60 mg/kg/bodyweight retinoic acid (RA) in olive oil at embryonic day 10 (E10). Amniocentesis was performed at multiple gestational time points on MMC fetuses, RA-exposed fetuses without MMC and control fetuses. AF PLA2 levels were analyzed by a fluorescent enzyme activity assay. PLA2 isoforms were determined by measuring activity in the presence of specific inhibitors. RESULTS: There was no difference in AF PLA2 activity between groups on E15. PLA2 activity was significantly increased in MMC fetuses on E17, E19 and E21 (p < 0.001). Secretory PLA2 primarily accounted for the overall greater activity. CONCLUSIONS: PLA2 levels are elevated in the AF of fetal rats with MMC and may contribute to ongoing neural injury. This pathway may be a useful drug target to limit ongoing damage and better preserve neurologic function.

Labor induction utilizing the Foley balloon: a randomized trial comparing standard placement versus immediate removal.

OBJECTIVE: To compare time to delivery between two induction procedures. The Foley balloon is a mechanical method for cervical ripening. However, the device may also result in endogenous prostaglandin release following separation of the chorionic membrane and decidua. Prolonged Foley placement may therefore be unnecessary for successful labor induction. METHOD: Randomized controlled trial of labor induction at LAC+USC Medical Center between 2010 and 2013. Subjects were assigned to either (a) standard placement of the Foley balloon or (b) Foley balloon insufflation and immediate removal. Oxytocin was administered to all subjects not in active labor after 12 h. Delivery information and neonatal outcomes were documented and all patients were followed for 6 weeks for adverse events. RESULT: A total of 79 women were included in the analysis (37 standard and 42 immediate). Induction time was 8.6 h longer in the immediate removal group (23.5 vs 32.1, P=0.002), but the difference in delivery within 24 h did not meet the statistical significance (46.0 vs 28.6%, P=0.11). Similar rates of cesarean delivery, epidural use and abnormal APGAR scores were observed. After controlling for number of vaginal exams and duration of rupture, a decreased risk of infection was observed in the immediate removal group (odds ratio=0.08, 95% confidence interval=0.007 to 0.93, P=0.04). Further, when the analysis was stratified by parity, differences in induction time only persisted in nulliparous women. CONCLUSION: Immediate removal of the Foley balloon may lead to longer overall induction time, but a lower risk of infection. Parous women may be particularly good candidates for this type of induction.

Role of low placental share in twin-twin transfusion syndrome complicated by intrauterine growth restriction.

OBJECTIVES: Prior studies have demonstrated that donor twin survival following treatment of twin-twin transfusion syndrome (TTTS) was highly associated with donor intrauterine growth restriction (IUGR). Here, we hypothesized that donor IUGR may be attributed in part to low placental share. STUDY DESIGN: The study population consisted of all patients who underwent laser treatment for TTTS at a single institution between 2006-2010. Only those pregnancies with dual survival at birth were included so that placental share information could be interpreted. We examined the relationships between Quintero Stage (with separate analysis of Stage III patients with critically abnormal donor Doppler findings) and low placental share (defined as ≤ 30%) with IUGR (<10th percentile) using chi-square analysis and multivariable logistic regression modeling. RESULTS: Of 210 patients treated, 159 (75.7%) had dual survivors at birth. Of these, placental share was documented in 90 cases (56.6%). Twenty-seven (30.0%) had low placental share, and 37 (41.1%) had IUGR. IUGR was associated with low placental share (63.0% vs. 31.7%, P = 0.0116). IUGR was also associated with Stage III patients (57.4% vs. 23.3%, P = 0.0021), and in particular with Stage III patients with donor involvement (77.8% vs. 25.4%, P < 0.0001). In logistic regression modeling, both low placental share and Stage III with donor involvement were independent risk factors for IUGR (OR = 3.5 [1.2-10.3], P = 0.0206, and OR = 10.1 [3.3-30.6], P < 0.0001, respectively). CONCLUSIONS: Donor IUGR in TTTS pregnancies appears to be associated, in part, with low placental share.