Prognostic value of the aortic isthmus Doppler assessment on late onset fetal growth restriction.

Background As conflicting results have been reported about the association of reversed flow on the aortic isthmus (AoI) and adverse perinatal results in fetal growth restriction (FGR), we aim to compare perinatal outcomes (including tolerance to labor induction) of late-onset FGR between those with anterograde and reversed AoI flow. Methods This was an observational retrospective cohort study on 148 singleton gestations diagnosed with late-onset FGR (diagnosis ≥32+0 weeks), with an estimated fetal weight (EFW) <10th centile and mild fetal Doppler alteration: umbilical artery (UA) pulsatility index (PI) >95th centile, middle cerebral artery (MCA)-PI <5th centile or cerebral-placental ratio <5th centile. Anterograde AoI flow was present in n=79 and reversed AoI flow in n=69. Delivery was recommended from 37 weeks in both groups. Perinatal results were compared between the groups. Results The global percentage of vaginal delivery of fetuses with anterograde and reversed blood flow was 55.7% vs. 66.7% (P=0.18) and the percentage of cesarean section (C-section) for non-reassuring fetal status was 12.7% vs. 15.9% (P=0.29), respectively. When evaluating those that underwent labor induction, the vaginal delivery rate was 67.9% vs. 77.2% (P=0.17), respectively. There were no significant differences regarding any other perinatal variables and there were no cases of severe morbidity or mortality. Conclusion We observed that the presence of reversed AoI flow does not worsen perinatal outcomes on fetuses with late-onset growth restriction with mild Doppler alterations. Attempt of labor induction is feasible in these fetuses regardless of the direction of AoI flow.

Time remaining in labor and probability of vaginal delivery as a function of the angle of progression in a low risk population with a normal first stage of labor. In-house observational study and comparison with the data in the literature.

BACKGROUND: The aim of the study was to investigate whether the angle of progression (AoP), as measured by transperineal ultrasound, was predictive of both the time remaining in labor and vaginal delivery. METHODS: This was a prospective observational cohort study involving 270 low-risk women with singleton pregnancies at term. The AoP, measured at the end of the first stage of labor, was used as a predictive variable of time remaining in labor and mode of delivery. The Kaplan Meier and Cox algorithms were used to evaluate the time elapsed between AoP measurement and delivery as a function of AoP. Instead, logistic regression was used to calculate the adjusted probability of vaginal delivery as a function of AoP. RESULTS: Of the 270 women enrolled, 15 (5.6%) delivered by cesarean section and 33 (12.1%) by vacuum or forceps. The AoP, stratified by quartiles, was a significant predictor of the time remaining in labor, even after adjustment for possible confounders (Body Mass Index [BMI], oxytocin administration and parity). The mean±SD second stage of labor length for each AoP quartile was 134±25, 126±18, 96±33 and 58±23 minutes (P value<0.001, ANOVA). The mean±SD probability of a vaginal delivery expressed as a function of the AoP quartile (adjusted for BMI) was 51.5±0.16%, 81.5±0.10%, 97.0±0.16% and 99.3±0.004% at the AoP of the 1st, 2nd, 3rd and 4th quartiles, respectively, (P value<0.001 ANOVA). CONCLUSIONS: The AoP was directly associated with the time remaining in labor and was predictive of a successful vaginal delivery; however, the impact on clinical practice seems low.