Cesarean Delivery For Nonreassuring Fetal Status Research Articles

670 Neonatal outcomes after cesarean for non-reassuring fetal status in the first stage of labor

Non-reassuring fetal status (NRFS) is the second most common indication for cesarean delivery (CD) accounting for 1 in 4 cesareans. We sought to evaluate neonatal outcomes following CD for NRFS. This was a secondary analysis of a prospective cohort study. We included singleton term pregnancies admitted for labor or induction of labor between 2010-2014. The primary outcome was fetal acidemia defined as umbilical artery (UA) pH < 7.1. Secondary outcomes were UA base excess, lactate, and neonatal composite morbidity (hypoxic-ischemic encephalopathy, meconium aspiration syndrome, hypothermia treatment, intubation, mechanical ventilation, neonatal seizure, death). The exposure was first stage CD for any indication that included NRFS and the control group was all other deliveries. Multivariable logistic regression and the Zhang method was used to estimate relative risk and adjust for confounders. We also performed a sensitivity analysis of patients who underwent CD for the sole indication of NRFS. Of the 8580 patients in the cohort, 721 (8.4%) had a first stage CD for NRFS. Among these, 476 (66.0%) were for the sole indication of NRFS. The risk of fetal acidemia was 5 times higher among patients undergoing CD for NRFS compared to all other deliveries (7.3% vs 1.2%, aRR 5.45[95% CI 3.35-8.68]). UA base excess and lactate were higher among patients with CD for NRFS. CD for NRFS was associated with an increased risk of composite neonatal morbidity (4.0% vs 1.0%, aRR 2.52 [95% CI 1.30-4.78]). After restricting the analysis to patients who had CD for the sole indication of NRFS, the risk of fetal acidemia and neonatal morbidity remained significantly higher in the CD for NRFS group than control deliveries. CD for NRFS is associated with an increased risk of fetal acidemia and composite neonatal morbidity. Although the vast majority of infants delivered for NRFS have normal outcomes, these results suggest that the diagnosis of NRFS using continuous fetal monitoring in labor is predictive of adverse outcomes.

961 Patient decisions regarding fetal monitoring in the periviable period and association with outcomes

Management of delivery at periviable gestation requires complex counseling and decision making, including difficult choices about fetal monitoring and intervention for fetal benefit. It is not clear how patients view these decisions, or how these decisions impact outcomes. We hypothesize that, when offered, a significant number of patients forgo monitoring and intervention in the periviable period. Retrospective cohort study of non-anomalous singleton pregnancies delivering between 23w0d and 25w6d at a tertiary care center from 2015 to 2020. Since 2015, we offer patients at these gestational ages options for fetal monitoring, intervention for fetal benefit, and active resuscitation of a liveborn neonate. We aim to characterize the frequency of patients desiring intervention for fetal benefit and identify associated patient characteristics, as well as describe the association with cesarean delivery (CD) and intrapartum demise. 50 subjects were included. 78% desired intervention for fetal benefit, and 84% desired resuscitation if the neonate was born alive, varying significantly by gestational age (Figure). Those desiring intervention were less likely to have a college degree (27% vs 80%, p=0.02) and be nulliparous (46.2% vs 81.8%, p=0.03) (Table). 69% of pregnancies in which intervention was desired resulted in CD (27/39), of which 85% were classical (23/27). Most were in the context of malpresentation (66.7%, 18/27), though 43% (9/21) of patients with cephalic presentation desiring intervention underwent CD for nonreassuring fetal status. Intrapartum demise occurred in 45% (5/11) of pregnancies in which monitoring was not performed. While a majority of patients between delivering between 23w0d and 25w6d desired monitoring and intervention for fetal benefit, this varied significantly by gestational age and patient characteristics. The decision to perform monitoring and intervention for fetal benefit was associated with high frequency of CD, while the decision to forgo monitoring was associated with high frequency of intrapartum demise.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Prostaglandins and cesarean delivery for nonreassuring fetal status in patients delivering small-for-gestational age neonates at term

Objective: Growth-restricted fetuses have been excluded from many randomized trials of prostaglandins for labor induction. As prostaglandins, particularly misoprostol, are associated with increased rates of cesarean delivery for nonreassuring fetal heart tracing, it is important to assess their safety in pregnancies at higher risk of this complication. The objective of this study was to estimate the association between use of prostaglandins for labor induction in term singleton pregnancies complicated by delivery of small-for-gestational age (SGA) neonates and the risk of cesarean delivery for nonreassuring fetal status (NRFS).Materials and methods: Retrospective cohort study of singleton deliveries ≥37 weeks following induction of labor in patients with SGA (birthweight <10% percentile for gestational age). Patients with prior cesarean delivery or neonates with major congenital anomalies were excluded. Patients were categorized by exposure to prostaglandins. The primary outcome was cesarean delivery for NRFS. Secondary outcomes were any cesarean delivery, a composite of a 5-min Apgar score <7, admission to the neonatal intensive care unit, or neonatal death, and a composite of maternal morbidity (transfusion, postpartum hemorrhage, wound infection, endometritis, fever). Propensity scores for exposure were estimated using a logistic regression model, including parity, comorbidities, and Bishop score. Stabilized weights from inverse probability of treatment weighting were used. Outcomes were compared with relative risks (RRs) and 95% confidence intervals (CIs).Results: There were 1097 patients: 587 (53.5%) exposed to prostaglandins and 510 (46.5%) unexposed. Covariates were balanced in the stabilized sample. Overall, 166 (15.1%) patients had cesarean deliveries for NRFS. In unadjusted analysis, prostaglandin use was associated with an increased RR of cesarean for NRFS (18.3 versus 11.0%, RR: 1.71, 95% CI: 1.27–2.30). In propensity-score-weighted analysis, the RR for cesarean for NRFS was 1.22 (95% CI: 0.93–1.59). There was no significant association between prostaglandin exposure and all-cause cesarean delivery, maternal morbidity, or neonatal morbidity.Conclusion: In propensity score analysis, there was no association between the use of prostaglandins for labor induction at term and cesarean for NRFS in pregnancies complicated by SGA. However, given the retrospective nature of the study, these results should be interpreted with caution.

Liberal versus Indicated Maternal Oxygen Supplementation in Labor: A Before-and-After Trial.

Although supplemental oxygen (SO2) is routinely administered to laboring gravidas, benefits and harms are not well studied. This article compares strategies of liberal versus indicated SO2 therapy during labor on cesarean delivery (CD) rate and neonatal outcomes. A controlled, before-and-after trial of laboring women with term, singleton pregnancies. During an initial 8-week period, maternal SO2 was administered at the discretion of the provider followed by an 8-week period where SO2 was to be given only for protocol indications. Our study included 844 women. There was no difference in number of women receiving SO2 (53% liberal vs. 50% indicated; p = 0.33). For those receiving SO2, there was no difference in SO2 duration (median, 89 minutes [interquartile range, 42-172] vs. 87 minutes [36-152]; p = 0.42). There were no differences in overall CD rate (20% vs. 17%; p = 0.70), CD for nonreassuring fetal status, or use of intrauterine resuscitative measures. There were more 5-minute APGAR < 7 in the indicated group, but no difference in umbilical artery pH < 7.1 or neonatal intensive care unit (NICU) admission. Approximately half of women receive SO2 intrapartum regardless of a strategy of liberal or indicated oxygen use. There were no clinically significant differences in outcomes between strategies.

356: Propensity score analysis of prostaglandin use and cesarean delivery for nonreassuring fetal status in small for gestational age fetuses at term

Growth restricted fetuses have been excluded from many randomized trials of prostaglandin use. The objective of this study was to estimate the association between use of prostaglandins for labor induction in term small for gestational age (SGA) fetuses and the risk of cesarean delivery for nonreassuring fetal status (NRFS). In a retrospective cohort study of consecutive deliveries ≥37 weeks, we analyzed induction of labor in patients with SGA fetuses defined as birthweight <10th%ile for gestational age. Patients with prior cesarean were excluded. Patients were categorized by exposure to prostaglandins. The primary outcome was cesarean delivery for NRFS. Secondary outcomes were any cesarean and a composite of 5-minute Apgar score <7 or admission to higher level nursery. Propensity scores for exposure were estimated using a logistic regression model including parity, comorbidities, and Bishop score. The propensity scores were trimmed at the non-overlapping tails to ensure positivity and were assessed for balance of covariates. Outcomes were compared between propensity score-matched exposed and unexposed patients. Of 1153 patients meeting inclusion criteria, 611 (53.0%) were exposed to prostaglandins and 542 (47.1%) were not. Misoprostol was the most common type of prostaglandin (73.6%). Prostaglandin use was strongly associated with nulliparity and low Bishop score (p<0.001). In unadjusted, non-propensity score-matched analysis, prostaglandin use was associated with an increased risk of cesarean for NRFS (OR 2.14, 95% CI 1.30, 3.50). In the propensity score-matched analysis of 290 exposed and 290 unexposed patients, use of prostaglandins was not associated with a significant risk of cesarean for NRFS (OR 1.32, 95%CI 0.68, 2.54). There was also no association between prostaglandin use and the secondary outcomes. We found no independent association between the use of prostaglandins for labor induction in term SGA fetuses and cesarean for NRFS after adjusting for factors associated with prostaglandin use. This suggests that withholding prostaglandins from patients with SGA fetuses may be unwarranted.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

8: Oxygen for category ii intrauterine fetal resuscitation: a randomized, noninferiority trial

Approximately 2/3 of laboring women receive supplemental oxygen (O2) in an attempt to reverse perceived fetal hypoxemia and prevent acidosis. O2 supplementation is routinely used in patients with Category II fetal heart tracings (FHT). However, this liberal use of intrapartum O2 may not be beneficial, particularly since hyperoxygenation in neonates is harmful. We tested the hypothesis that room air (RA) for Category II FHT is not worse than O2 in reducing umbilical artery (UA) lactate, a marker of metabolic acidosis and neonatal morbidity. This was a randomized controlled noninferiority trial conducted from June 2016 to June 2017. Singleton pregnancies ≥ 37 weeks with Category II FHT necessitating intrauterine resuscitation in active labor (≥6cm) were randomized to RA or 10L/min O2 by face mask until delivery. The primary outcome was UA lactate measured by cord gases collected at delivery. Secondary outcomes were other UA gas components, cesarean delivery for nonreassuring fetal status (NRFS), and operative vaginal delivery. Assuming a mean UA lactate of 3.5 ± 1.6 mmol/L in patients with Category II FHT, 98 patients were needed for 90% power to detect non-inferiority with a margin of 30% and 1-sided alpha of 0.025. We increased the sample size to 114 patients to accommodate 15% loss to unattainable cord gases. Noninferiority was declared if the mean difference in lactate between RA and O2 was <1.0 mmol/L. Analysis was by intention-to-treat. Of the 114 patients randomized, 99 with paired cord gases were included in the intention-to-treat analysis; 48 O2 and 51 RA. There was no difference in mean UA lactate between patients randomized to O2 and RA (mean [95%CI], 3.4 [3.0, 3.8] vs 3.5 [3.1, 4.0]), P=0.69). The mean difference in UA lactate was 0.1 mmol/L (95% CI -0.5, 0.7), which is within the non-inferiority margin (Figure). There were no differences in other UA gas components, operative vaginal delivery or cesarean delivery for NRFS between groups (Table). Among patients with Category II FHT in active labor, intrauterine resuscitation with RA is not inferior to O2 in improving UA lactate. (ClinicalTrials.gov number NCT02741284).View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Is Use of Misoprostol Associated With Failed Induction in Pregnancies With Suspected Placental Insufficiency? [12O

INTRODUCTION: Although misoprostol (MP) has demonstrated efficacy for cervical ripening, a concern with use of MP is uterine tachysystole, leading to fetal intolerance of labor and cesarean delivery (CD). We sought to determine whether indicators of placental insufficiency were associated with higher rates of failed induction and CD in pregnancies when MP was used for cervical ripening. METHODS: Population based retrospective cohort study of patients who underwent MP induction between May 2008-2013. Maternal and labor characteristics were compared between patients with FGR (&lt;10th% estimated fetal weight on ultrasound), oligohydramnios, preeclampsia, and infants born SGA (birth weight less than 10th%). Primary outcome was rate of CD. Secondary outcomes included CD for nonreassuring fetal status (NRFS). Multivariable logistic regression estimated association between indicators of placental insufficiency on the outcome of CD. RESULTS: Of 1,617 inductions during the 6 year period, 580 patients were induced using MP. FGR was suspected in 106 (18.2%). FGR was not associated with higher CD rate in MP inductions [22% versus 29%, p=0.11 (aOR 0.89, 95% CI 0.68-1.16)]. Similarly neither SGA nor oligohydramnios were associated with an increased CD rate, however preeclampsia did demonstrate a trend toward increased CD, aOR 1.21 (95% CI 0.97-1.51). The rate of CD for NRFS was similar between those with FGR and those without FGR (16% vs 15%, p=0.7). CONCLUSION: Despite a biologically plausible concern that MP induction in the setting of FGR and other indicators of placental insufficiency may increase risk for CD and CD for NRFS, our data does not support this.