Side effects from epidural analgesia in laboring women and risk of cesarean delivery.

BACKGROUND: Epidural analgesia may cause maternal hypotension and changes in the fetal heart rate. The implications of such side effects on the course of labor and delivery are incompletely understood. OBJECTIVE: This study aimed to assess whether the occurrence of maternal or fetal side effects associated with labor epidural analgesia increased the risk for cesarean delivery. STUDY DESIGN: This was a cohort study of all women who underwent epidural analgesia during labor for the period October 1, 2020 to December 31, 2020. Excluded were cases of multiples, fetal death, noncephalic presentation, and gestational age at birth <37.0 weeks. Maternal vital signs and fetal heart rate tracings for the 1 hour before and 1 hour after epidural analgesia was administered were reviewed. The occurrence of maternal hypotension, defined as a continuous variable and dichotomized into a decrease in maternal systolic blood pressure to <90 mm Hg or a drop in systolic blood pressure by >20% below the last value before epidural analgesia was administered, was related to changes in the fetal heart rate category. The principal outcome was cesarean delivery rate; binary logistic regression analysis was used to control for confounders, and mediation model analysis was used to quantify the extent to which significant variables participated in the causation pathway to cesarean delivery (SPSS version 28 was used for the analyses). RESULTS: A total of 439 women met the study criteria. Significant adverse reactions owing to epidural occurred in 184 of 439 women (41.9%) and included severe maternal hypotension in 159 of 439 participants (36.2%) and worsening fetal heart rate category in 50 of 439 participants (11.4%). The logistic regression analysis revealed that cervical dilation at epidural (P=.03), the duration of labor after epidural (P<.001), and worsening fetal heart rate category within 60 minutes of epidural administration (P=.01) were independently associated with recourse to cesarean delivery. The mediation analysis showed that both cervical dilatation at epidural administration and worsening fetal heart rate category had significant direct and indirect effects in the pathway to cesarean delivery. CONCLUSION: Worsening fetal heart rate category related to labor epidural independently increased the risk for cesarean delivery.

Rate of decline of fetal base excess after neuraxial anesthesia for scheduled cesarean delivery.

BACKGROUND: In scheduled cesarean deliveries, the rate of decrease in the umbilical artery pH is related to the severity of maternal hypotension and the interval from spinal placement to delivery. Base excess values have greater use than umbilical artery pH values to time the duration of fetal acidemia because they demonstrate a linear rather than logarithmic correlation with the degree of acidosis. OBJECTIVE: This study aimed to evaluate the rate of decline in the fetal base excess in scheduled cesarean deliveries that were converted to emergency cesarean delivery owing to fetal bradycardia following spinal anesthesia. STUDY DESIGN: All cases of scheduled cesarean deliveries in gestations at >34 weeks' gestation under spinal anesthesia that were converted to emergency cesarean deliveries owing to fetal bradycardia in the period May 2019 to May 2021 were reviewed. Included were those with (1) a preoperative reactive nonstress test and (2) fetal acidemia (umbilical artery pH <7.20). Excluded were those with anesthesia other than spinal and a birthweight below the 10th percentile for gestational age. Time intervals between the completion of spinal anesthesia and delivery were calculated and related to umbilical cord gas analytes. RESULTS: From a cohort of 1064 scheduled cesarean deliveries, 7 fulfilled the study criteria yielding 8 neonates. Mean ± standard error of the mean interval of spinal anesthesia to delivery was 15.0±1.9 minutes, and the decrease in mean blood pressure after spinal anesthesia was 39.1±3.0 mm Hg. Umbilical artery base excess ranged from -5.2 to -16.6 mmol/L (median, -8.0). Based on published normative data of prelabor fetal umbilical artery base excess (-2±0.6 mmol/L), the mean rate of base excess decrease was 0.38±0.25 mmol/minute. CONCLUSION: The rate of decrease in base excess when scheduled cesarean deliveries are converted to emergency cesarean deliveries owing to fetal bradycardia related to spinal anesthesia (1 mmol/2.6 min) matches the estimated rate of loss of base excess (1 mmol/2-3 minutes) reported in cases of severe bradycardia or sentinel events during labor.

Society for Maternal-Fetal Medicine Consult Series #60: Management of pregnancies resulting from in vitro fertilization.

The use of assisted reproductive technology has increased in the United States in the past several decades. Although most of these pregnancies are uncomplicated, in vitro fertilization is associated with an increased risk for adverse perinatal outcomes primarily caused by the increased risks of prematurity and low birthweight associated with in vitro fertilization pregnancies. This Consult discusses the management of pregnancies achieved with in vitro fertilization and provides recommendations based on the available evidence. The recommendations by the Society for Maternal-Fetal Medicine are as follows: (1) we suggest that genetic counseling be offered to all patients undergoing or who have undergone in vitro fertilization with or without intracytoplasmic sperm injection (GRADE 2C); (2) regardless of whether preimplantation genetic testing has been performed, we recommend that all patients who have achieved pregnancy with in vitro fertilization be offered the options of prenatal genetic screening and diagnostic testing via chorionic villus sampling or amniocentesis (GRADE 1C); (3) we recommend that the accuracy of first-trimester screening tests, including cell-free DNA for aneuploidy, be discussed with patients undergoing or who have undergone in vitro fertilization (GRADE 1A); (4) when multifetal pregnancies do occur, we recommend that counseling be offered regarding the option of multifetal pregnancy reduction (GRADE 1C); (5) we recommend that a detailed obstetrical ultrasound examination (CPT 76811) be performed for pregnancies achieved with in vitro fertilization and intracytoplasmic sperm injection (GRADE 1B); (6) we suggest that fetal echocardiography be offered to patients with pregnancies achieved with in vitro fertilization and intracytoplasmic sperm injection (GRADE 2C); (7) we recommend that a careful examination of the placental location, placental shape, and cord insertion site be performed at the time of the detailed fetal anatomy ultrasound, including evaluation for vasa previa (GRADE 1B); (8) although visualization of the cervix at the 18 0/7 to 22 6/7 weeks of gestation anatomy assessment with either a transabdominal or endovaginal approach is recommended, we do not recommend serial cervical length assessment as a routine practice for pregnancies achieved with in vitro fertilization (GRADE 1C); (9) we suggest that an assessment of fetal growth be performed in the third trimester for pregnancies achieved with in vitro fertilization; however, serial growth ultrasounds are not recommended for the sole indication of in vitro fertilization (GRADE 2B); (10) we do not recommend low-dose aspirin for patients with pregnancies achieved with IVF as the sole indication for preeclampsia prophylaxis; however, if 1 or more additional risk factors are present, low-dose aspirin is recommended (GRADE 1B); (11) given the increased risk for stillbirth, we suggest weekly antenatal fetal surveillance beginning by 36 0/7 weeks of gestation for pregnancies achieved with in vitro fertilization (GRADE 2C); (12) in the absence of studies focused specifically on timing of delivery for pregnancies achieved with IVF, we recommend shared decision-making between patients and healthcare providers when considering induction of labor at 39 weeks of gestation (GRADE 1C).

Neonatal complications in vacuum-assisted vaginal delivery: are they associated with number of pulls, cup detachments, and duration of vacuum application?

PURPOSE: To explore whether the characteristics of vacuum delivery are associated with the occurrence of head injury and neonatal complications. METHODS: Retrospectively cohort study of vacuum-assisted attempted vaginal deliveries of singletons. We studied the association of total duration of vacuum application and number of pulls and cup dislodgement with (1) primary outcome: the occurrence of major (subgaleal hemorrhage, skull fracture, and intracranial hemorrhage) or minor (cephalohematoma, scalp laceration more extensive than simple abrasions) neonatal head injuries and (2) secondary outcome: the occurrence of neonatal complications, including 5-min Apgar score <7, umbilical artery pH < 7.10, shoulder dystocia, or need for neonatal intensive care unit admission. Logistic regression analysis was used to control for confounders. RESULTS: Vacuum-assisted delivery was attempted in 555 women. It was successful in 515 cases, and it failed in 40 (7.2 %). Head injury occurred in 32 (6.2 %) of vaginally delivered neonates, and it was related to duration of vacuum application (P = 0.004) and birth weight (P = 0.048). However, the associations lost a statistical significance at the multivariate analysis. Neonatal complications occurred in 25 cases (5 %), and they were associated with meconium-stained amniotic fluid (P < 0.001) and duration of vacuum application (P = 0.03) at the multivariate analysis. However, most of the complications were actually associated with the need for vacuum delivery rather than the procedure itself. CONCLUSION: Neonatal head injury after vacuum application is not independently related to total duration of vacuum application, number of pulls, or cup dislodgements.

Risk factors for cerebral palsy in PPROM and preterm delivery with intact membranes (.).

OBJECTIVE: Gestational age (GA) at delivery and spontaneous prematurity are independent risk factors for cerebral palsy (CP). The aim of this study is to investigate perinatal risk factors for CP in spontaneous preterm delivery. METHODS: A retrospective cohort study of all single pregnancies complicated by spontaneous preterm labor (PTL) or PPROM with delivery at <34 weeks from January 2006 to December 2012 was performed. We compared demographic, obstetric, neonatal, and placental histology variables in cases of spontaneous preterm birth in reference to the development of CP. Statistical analysis included chi-square, one-way ANOVA and logistic regression analysis. p < 0.05 was considered significant. RESULTS: Two hundred sixty-one women were included for this study. Of 249 survivors, 5 babies died during the first year of life, 52 did not fulfill the inclusion criteria for neurologic follow-up, and 24 were lost to follow up. Thus 168 infants in the study cohort underwent neurologic follow-up. We observed 26 cases of CP. Factors related to CP were lower GA at PROM (p = 0.007) and longer latency from PPROM to delivery (p = 0.002) in the PPROM group, lower GA at delivery (p < 0.001) and presence of funisitis (p <0.001) in the PTL group. CONCLUSIONS: GA at membrane rupture in PPROM and GA at delivery in PTL are significantly associated with CP. A process leading to neurological damage may be initiated at the moment of membranes rupture in cases of PPROM and at the time of PTL in the group with intact membranes.

Effect of oxytocin during labor on neonatal acidemia.

OBJECTIVE: To assess the factors affecting neonatal acidemia, including occurrence of tachysystole/hypertonus in fetuses exposed to oxytocin during labour and with continuously-monitored fetal heart rate (FHR) tracings. METHODS: Prospective observational study of all women with term pregnancies who received oxytocin for induction/augmentation of labour. FHR tracings were prospectively classified using ACOG classification. Independent predictors of neonatal acidemia were identified using multivariate linear regression with p < 0.05 considered significant. RESULTS: We included 430 women, 236 of whom (54.9%) had spontaneous onset of labour. The duration of active phase of the second stage of labour and the presence of abnormal FHR tracing during labour were significantly associated with UA pH (p < 0.001) and BE (p < 0.001), while maximum dose of oxytocin (p < 0.17; p < 0.7) and tachysystole (p < 0.9; p < 0.8) were not. At logistic regression, the duration of active phase of the second stage of labour was independently predictive of neonatal acidemia (p < 0.009) while abnormal FHR tracing approached significance (p < 0.088). CONCLUSIONS: In women receiving oxytocin during labour, the duration of active phase of the second stage of labour correlates with neonatal acidemia, whereas maximum dose of oxytocin, duration of oxytocin administration and occurrence of tachysystole during labour do not.