Occiput Posterior Position Research Articles

Clinical case of feto-fetal transfusion syndrome development in dichorionic twin pregnancies with fused placentas

This article analyzes a clinical case of feto-fetal transfusion syndrome development in dichorionic diamniotic twin pregnancies with fused placentas. Feto-fetal transfusion syndrome is a typical complication of the monochorionic type of placentation, but it is quite rare in the dichorionic type of placentation. In this case, the syndrome development became possible due to the close anatomical location of the placentas, which probably led to their fusion and the development of unbalanced interplacental anastomoses. During the observation of the patient in an antenatal clinic, no ultrasound signs of feto-fetal transfusion syndrome were detected. At a 25+5-week gestation period, the patient complained of cramping pains in the lower abdomen and liquid discharge from the genital tract. The patient was hospitalized at the second stage of labor and gave birth through the natural birth canal. The first fetus had polyhydramnios, the second one having extremely low water. The first was a premature boy in the occiput posterior position weighing 980 g and 32 cm in height in a state of severe asphyxia with an Apgar score of 1, 4 and 6 points. The second was a premature boy in breech position weighing 490 g and 32 cm in height, also in a state of severe asphyxia with an Apgar score of 1, 4 and 6 points. The first child developed severe multiple organ failure, which caused death on the twelfth day. The second newborn developed respiratory distress followed by death on the second day of the neonatal period.

A dynamic prediction score for obstetric anal sphincter injury among nulliparous women delivering vaginally.

To develop a risk score for obstetric anal sphincter injury (OASI) occurrence among nulliparous women delivering vaginally, based on data available at admission for delivery and as labor progresses. A retrospective study of all nulliparous women who delivered vaginally between March 2011 and January 2021. Characteristics were compared between OASI and no-OASI groups. Multivariable analyses were performed to identify independent risk factors for OASI occurrence. OASI occurred in 453 (1.7%) of 26081 women who met the inclusion criteria. The following variables were independently associated with OASI: maternal height (adjusted odds ratio [aOR] 0.97, 95% confidence interval (CI) 0.95-0.99), hypertensive disorders (aOR 1.74, 95% CI 1.03-2.95), sonographic fetal weight estimation (aOR 1.00, 95% CI 1.00-1.00), second-stage duration (aOR 1.00, 95% CI 1.00-1.00), occiput posterior position (aOR 2.87, 95% CI 1.79-4.62), and episiotomy performance (aOR 0.63, 95% CI 0.47-0.84). In a risk score based on variables available at admission for delivery, the presence of two factors was associated with 4.3% OASI risk. Upon incorporating intrapartum variables, the presence of two risk factors was associated with 2.9% OASI rate. A dynamic risk score for OASI occurrence based on data available at admission for delivery and as delivery progresses can assist in counseling regarding OASI risk. A dynamic risk score for obstetric anal sphincter injury occurrence based on data available at admission for delivery and intrapartum was developed.

Case 2: Early-Onset Neonatal Sepsis in a Term Neonate

Case 2: Early-Onset Neonatal Sepsis in a Term Neonate

Prophylactic manual rotation of occiput posterior and transverse positions to decrease operative delivery: the PROPOP randomized clinical trial

Persistent occiput posterior and occiput transverse positions are the most common malpositions of the fetal head during labor and are associated with prolonged second stage of labor, cesarean deliveries, instrumental deliveries, severe perineal tears, postpartum hemorrhage, and chorioamnionitis. Manual rotation is one of several strategies described to deal with these malpositions. This study aimed to determine if the trial of prophylactic manual rotation at the early second stage of labor is associated with a decrease in operative deliveries (instrumental and/or cesarean deliveries). We conducted a multicenter, open-label, randomized controlled trial in 4 French hospitals. Women with singleton term pregnancy and occiput posterior or occiput transverse position confirmed by ultrasound at the early second stage of labor and with epidural analgesia were eligible. Women were randomly assigned (1:1) to either undergo a trial of prophylactic manual rotation of occiput posterior or occiput transverse position (intervention group) or no trial of prophylactic manual rotation (standard group). The primary outcome was operative delivery (instrumental and/or cesarean deliveries). The secondary outcomes were length of the second stage of labor, maternal complications (postpartum hemorrhage, operative complications during cesarean delivery, episiotomy and perineal tears), and neonatal complications (Apgar score of <5 at 10 minutes, arterial umbilical pH of <7.10, neonatal injuries, neonatal intensive care unit admission). The main analysis was focused on intention-to-treat analysis. From December 2015 to December 2019, a total of 257 women (mean age, 30.4 years; mean gestational age, 40.1 weeks) were randomized: 126 were assigned to the intervention group and 131 were assigned to the standard group. Operative delivery was significantly less frequent in the intervention group compared with the standard group (29.4% [37 of 126] vs 41.2% [54 of 131]; P=.047; differential [intervention-standard] [95% confidence interval]=-11.8 [-15.7 to-7.9]; unadjusted odds ratio [95% confidence interval]= 0.593 [0.353-0.995]). Women in the intervention group were more likely to have a significantly shorter second stage of labor. Trial of prophylactic manual rotation of occiput posterior or occiput transverse positions during the early second stage of labor was statistically associated with a reduced risk of operative delivery. This maneuver could be a safe strategy to prevention operative delivery.

Delivery Mode After Manual Rotation of Occiput Posterior Fetal Positions: A Randomized Controlled Trial.

To evaluate whether manual rotation of fetuses in occiput posterior positions at full dilation increases the rate of spontaneous vaginal delivery. In an open, single-center, randomized controlled trial, patients with a term, singleton gestation, epidural analgesia, and ultrasonogram-confirmed occiput posterior position at the start of the second stage of labor were randomized to either manual rotation or expectant management. Our primary endpoint was the rate of spontaneous vaginal delivery. Secondary endpoints were operative vaginal delivery, cesarean delivery, and maternal and neonatal morbidity. Analyses were based on an intention-to-treat method. A sample size of 107 patients per group (n=214) was planned to detect a 20% increase in the percent of patients with a spontaneous vaginal delivery (assuming 60% without manual rotation vs 80% with manual rotation) with 90% power and alpha of 0.05. Between February 2017 and January 2020, 236 patients were randomized to either manual rotation (n=117) or expectant management (n=119). The success rate of the manual rotation maneuver, defined by conversion to an anterior position as confirmed by ultrasonogram, was 68%. The rate of the primary endpoint did not differ between the groups (58.1% in manual rotation group vs 59.7% in expectant management group (risk difference -1.6; 95% CI -14.1 to 11.0). Manual rotation did not decrease the rate of operative vaginal delivery (29.9% in manual rotation group vs 33.6% in expectant management group (risk difference -3.7; 95% CI -16.6 to 8.2) nor the rate of cesarean delivery (12.0% in manual rotation group vs 6.7% in expectant management group (risk difference 5.3; 95% CI -2.2 to 12.6). Maternal and neonatal morbidity was also similar across the two groups. Manual rotation of occiput posterior positions at the start of second stage of labor does not increase the rate of vaginal delivery without instrumental assistance. ClinicalTrials.gov, NCT03009435.

Can ultrasound on admission in active labor predict labor duration and a spontaneous delivery?

Identifying predictive factors for a normal outcome at admission in the labor ward would be of value for planning labor care, timing interventions, and preventing labor dystocia. Clinical assessments of fetal head station and position at the start of labor have some predictive value, but the value of ultrasound methods for this purpose has not been investigated. Studies using transperineal ultrasound before labor onset show possibilities of using these methods to predict outcomes. This study aimed to investigate whether ultrasound measurements during the first examination in the active phase of labor were associated with the duration of labor phases and the need for operative delivery. This was a secondary analysis of a prospective cohort study at Landspitali University Hospital, Reykjavík, Iceland. Nulliparous women at ≥37 weeks' gestation with a single fetus in cephalic presentation and in active spontaneous labor were eligible for the study. The recruitment period was from January 2016 to April 2018. Women were examined by a midwife on admission and included in the study if they were in active labor, which was defined as regular contractions with a fully effaced cervix, dilatation of ≥4 cm. An ultrasound examination was performed by a separate examiner within 15 minutes; both examiners were blinded to the other's results. Transabdominal and transperineal ultrasound examinations were used to assess fetal head position, cervical dilatation, and fetal head station, expressed as head-perineum distance and angle of progression. Duration of labor was estimated as the hazard ratio for spontaneous delivery using Kaplan-Meier curves and Cox regression analysis. The hazard ratios were adjusted for maternal age and body mass index. The associations between study parameters and mode of delivery were evaluated using receiver operating characteristic curves. Median times to spontaneous delivery were 490 minutes for a head-perineum distance of ≤45 mm and 682 minutes for a head-perineum distance of >45 mm (log-rank test, P=.009; adjusted hazard ratio for a shorter head-perineum distance, 1.47 [95% confidence interval, 0.83-2.60]). The median durations were 506 minutes for an angle of progression of ≥93° and 732 minutes for an angle of progression of <93° (log-rank test, P=.008; adjusted hazard ratio, 2.07 [95% confidence interval, 1.15-3.72]). The median times to delivery were 506 minutes for nonocciput posterior positions and 677 minutes for occiput posterior positions (log-rank test, P=.07; adjusted hazard ratio, 1.52 [95% confidence interval, 0.96-2.38]) Median times to delivery were 429 minutes for a dilatation of ≥6 cm and 704 minutes for a dilatation of 4 to 5 cm (log-rank test, P=.002; adjusted hazard ratio, 3.11 [95% confidence interval, 1.68-5.77]). Overall, there were 75 spontaneous deliveries; among those deliveries, 16 were instrumental vaginal deliveries (1 forceps delivery and 15 ventouse deliveries), and 8 were cesarean deliveries. Head-perineum distance and angle of progression were associated with a spontaneous delivery with area under the receiver operating characteristic curves of 0.68 (95% confidence interval, 0.55-0.80) and 0.67 (95% confidence interval, 0.55-0.80), respectively. Ultrasound measurement of cervical dilatation or position at inclusion was not significantly associated with spontaneous delivery. Ultrasound examinations showed that fetal head station and cervical dilatation were associated with the duration of labor; however, measurements of fetal head station were the variables best associated with operative deliveries.

Maternal positioning with flexed thighs to correct foetal occipito-posterior position in labour: A systematic review and meta-analysis

BackgroundFoetal occipto-posterior position during labour can contribute to negative outcomes. Encouraging women to adopt positions utilising thigh flexion with the aim of increasing pelvic diameters and promoting foetal rotation to the occpito-anterior position are often used. However, the efficacy of these strategies has not yet been determined. ObjectiveTo compare the effects of maternal hands and knees or lateral positions with flexed thighs versus control in rotating foetal occipito-posterior to occipito-anterior in the first stage of labour. MethodsThe databases such as MEDLINE/PubMed, CINAHL, Cochrane Central Register of Controlled Trials (CENTRAL) and Embase were searched with dates ranging from 1947 to 2019. We included randomised controlled trials (RCTs) that compared maternal hands and knees, and lateral positions incorporating flexed thighs (spine-femur angle of ≥ 90°) versus control to rotate foetal malposition in the first stage of labour and published in English. Methodological quality was assessed based on Cochrane's Risk of Bias 2 for randomized controlled trials. Two teams of researchers completed the study selection, quality assessment, data extraction and meta-analysis. ResultsSeven RCTs met our inclusion criteria (n = 1422). Whilst there was an increase in the rate of spontaneous foetal rotation from the occipito-posterior to the anterior position, particularly in the first hour after the intervention was adopted, this did not reach statistical significance (RR, 1.15; 95% CI, 0.96–1.39, p = 0.13). The effect was insufficient to influence rates of spontaneous vaginal birth (RR, 1.04; 95% CI, 0.85–1.26, p = 0.72) whilst there was a reduction in the duration of first stage labour (Mean-difference, -27.34; 95% CI, -45.96, -8.72, p = 0.004). ConclusionThis systematic review reports no significant correlation between maternal positioning with flexed thighs and foetal rotation from occipito-posterior to occipito-anterior position during first stage labour. The specific maternal positions tested did not impact on the majority of other labour and birth outcomes. Given that the majority of fetuses will rotate spontaneously to an occipito-anterior position it may be that maternal posturing facilitates earlier rotation in this group but has no effect on the subset of infants that would otherwise persist in the occipito-posterior position to birth.

The association between sonographic fetal head circumference, obstetric anal sphincter injury and mode of delivery: A retrospective cohort study.

There is no consensus to the implications of an increased sonographic fetal head circumference (HC) and its impact on delivery. To examine if there is any association between sonographic fetal HC, obstetric anal sphincter injury (OASIS) and mode of delivery. A retrospective cohort study of term, singleton births between April 2017 and March 2019 at a large regional hospital in Australia with a third trimester ultrasound. Logistic regressions were performed investigating sonographic fetal HC and additional risk factors for OASIS. Further multinomial logistic regressions assessed the relationship between the sonographic HC and mode of delivery. Odds ratios and their 95% CIs were reported. Of 667 eligible women, 487 (73%) had vaginal births, with 32 (6.6%) sustaining an OASIS and 180 (27%) had caesarean sections (CS). The sonographic fetal HC did not show an association with OASIS (odds ratio 1.005; CI 0.99-1.01, P=0.447). A statistically significant association (P<0.05) with OASIS was found with Asian ethnicity (4.38; 1.5-11.32), prolonged second stage (≥2h) (4.26; 1.57-10.49) and occiput posterior position (4.01; 1.08-11.92). For women with a sonographic fetal HC≥90th percentile, the odds of having CS compared to a spontaneous vaginal birth are 2.77 (95% CI: 1.36, 5.62; P=0.005) times higher than those who have a HC<90th percentile. This study does not support the use of sonographic fetal HC in assessing a woman's risk of sustaining an OASIS. Sonographic fetal HC is associated with mode of delivery.

Intrapartum sonographic assessment of the fetal head flexion in protracted active phase of labor and association with labor outcome: a multicenter, prospective study

To date, no research has focused on the sonographic quantification of the degree of flexion of the fetal head in relation to the labor outcome in women with protracted active phase of labor. This study aimed to assess the relationship between the transabdominal sonographic indices of fetal head flexion and the mode of delivery in women with protracted active phase of labor. Prospective evaluation of women with protracted active phase of labor recruited across 3 tertiary maternity units. Eligible cases were submitted to transabdominal ultrasound for the evaluation of the fetal head position and flexion, which was measured by means of the occiput-spine angle in fetuses in nonocciput posterior position and by means of the chin-to-chest angle in fetuses in occiput posterior position. The occiput-spine angle and the chin-to-chest angle were compared between women who had vaginal delivery and those who had cesarean delivery. Cases where obstetrical intervention was performed solely based on suspected fetal distress were excluded. A total of 129 women were included, of whom 43 (33.3%) had occiput posterior position. Spontaneous vaginal delivery, instrumental delivery, and cesarean delivery were recorded in 66 (51.2%), 17 (13.1%), and 46 (35.7%) cases, respectively. A wider occiput-spine angle was measured in women who had vaginal delivery compared with those submitted to cesarean delivery owing to labor dystocia (126±14 vs 115±24; P<.01). At the receiver operating characteristic curve, the area under the curve was 0.675 (95% confidence interval, 0.538-0.812; P<.01), and the optimal occiput-spine angle cutoff value discriminating between cases of vaginal delivery and those delivered by cesarean delivery was 109°. A narrower chin-to-chest angle was measured in cases who had vaginal delivery compared with those undergoing cesarean delivery (27±33 vs 56±28 degrees; P<.01). The area under the curve of the chin-to-chest angle in relation to the mode of delivery was 0.758 (95% confidence interval, 0.612-0.904; P<.01), and the optimal cutoff value discriminating between vaginal delivery and cesarean delivery was 33.0°. In women with protracted active phase of labor, the sonographic demonstration of fetal head deflexion in occiput posterior and in nonocciput posterior fetuses is associated with an increased incidence of cesarean delivery owing to labor dystocia. Such findings suggest that intrapartum ultrasound may contribute in the categorization of the etiology of labor dystocia.

A randomized controlled trial of prophylactic early manual rotation of the occiput posterior fetus at the beginning of the second stage vs expectant management

Women whose fetuses are in the occiput posterior head position at the time of delivery are known to have longer second stages of labor and more complicated deliveries including more operative deliveries (cesarean, forceps, or vacuum-assisted delivery) and more third- and fourth-degree lacerations than those whose fetuses are in the occiput anterior position. We hypothesized that rotating the fetus at the start of the second stage might decrease these complications. At Utah Valley Regional Medical Center, we randomized term (37 weeks or beyond), nulliparous patients with epidurals and a singleton fetus in the occiput posterior position to either attempted early manual rotation to occiput anterior or to a control group managed expectantly. The control group could later be rotated if indicated by the clinical setting. The primary outcome was the length of the second stage of labor. Dichotomous outcomes were compared utilizing the chi-square test, and continuous outcomes were compared utilizing the Student t test or Wilcoxon rank sum test.The sample size estimate was for 64 patients to be randomized (32 in each group) to show a difference of 36 minutes of pushing time between the 2 groups. We randomized 65 patients (33 to early manual rotation and 32 to control). When we examined a variety of baseline obstetrical characteristics, we found no statistically different values for the 2 groups. The early manual rotation group had a shorter median second stage of labor (65 minutes vs 82 minutes; P=.04). Early manual rotation of the occiput posterior fetus led to a shorter second stage of labor in this small randomized trial. Future larger randomized trials are needed to validate these findings.

3 Prophylactic Manual Rotation of Persistent Occiput Posterior to decrease operative Delivery: a Multicentric Randomized Trial

Persistent occiput posterior (POP) positions are the commonest malpresentations of the fetal head during labor and are associated with prolonged second stage of labor, cesarean, instrumental deliveries, obstetrical anal sphincter injuries, postpartum hemorrhage and chorioamnionitis. Manual rotation is one of several strategies described to deal with POP. The literature suggests that manual rotation of POP could decrease operative deliveries but no randomized study has confirmed these findings. The aim of this study was to determine if the trial of prophylactic manual rotation during the early second stage of labor is associated with a decrease risk of operative deliveries (instrumental and/or cesarean deliveries). This study was a prospective, randomized, controlled trial conducted in four French hospitals. Women with singleton term pregnancy and POP position confirmed by ultrasound at early second stage of labor and with epidural analgesia were eligible and randomized (1:1) to either receive the trial of prophylactic manual rotation of POP position (intervention group) or no trial of prophylactic manual rotation (standard group). The primary outcome was operative deliveries (instrumental and/or cesarean deliveries). From December 2015 to December 2019, 257 women were randomized: 126 assigned to the intervention group and 131 to the standard group. The groups did not differ in baseline characteristics. Operative delivery was significantly less frequent in the intervention (I) group compared to the standard (S) group (29.4 vs. 41.2%, p=.047, Differentiel (I-S) [95% confidence interval, CI] = -11.8 [-15.7;-7.9]; relative risk [95% CI] = 0.71 [0.51-1.00]). Women in the intervention group were more likely to have a significant shorter second stage of labor and have a neonate with a significant higher Apgar score at 5 minutes. The were no differences in other secondary outcomes. Trial of prophylactic manual rotation of persistent POP positions during the early second stage of labor is associated with a decrease risk of operative delivery.

512 Hands-and-knees position and incidence of occiput anterior position at birth: a systematic review and meta-analysis

Persistent occiput posterior (OP) and occiput transverse (OT) positions are associated with adverse maternal and neonatal outcomes. Our objective was to assess the efficacy of hands-and-knees to increase occiput anterior (OA) position in the second stage of labor or at time of delivery. An electronic search of five databases was performed. We included all randomized controlled trials of singleton gestations at ≥37 weeks that were randomized to either hands-and-knees position or control (i.e., any position other than hands-and-knees). The primary outcome was OA position in second stage of labor or at time of delivery. Secondary outcomes were change to OA position after initial intervention, as well as delivery and neonatal outcomes. A prespecified subgroup analysis for patients in labor was planned for the primary outcome. Meta-analysis was performed using the random-effects model expressed as relative risk (RR) or mean difference with 95% confidence intervals (CI). Heterogeneity was assessed using the I2 statistic. Of 1,079 studies screened, five met inclusion criteria (N=1,727 hands-and-knees position and N=1,641 controls). Duration of intervention varied from 10-60 minutes. Participants using hands-and-knees position did not have an increased rate of OA position during second stage of labor or at time of delivery (RR 1.03, 95% CI 0.92-1.14, 4 studies, 3,178 patients) or after initial intervention (RR 1.60, 95% CI 0.88-2.90, 4 studies, 788 patients). No difference was found on subgroup analysis of patients in labor (RR 1.06, 95% CI 0.87-1.29, 3 studies, 631 patients). Regional anesthesia use, duration of labor, rate of operative or cesarean deliveries, risk of perineal laceration, neonatal birth weight, and low Apgar scores did not differ between groups. Hands-and-knees position does not increase the incidence of OA position in labor or at time of delivery.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

The role of the angle of progression in the prediction of the outcome of occiput posterior position in the second stage of labor

Occiput posterior position is the most frequent cephalic malposition, and its persistence at delivery is associated with a higher risk of maternal and perinatal morbidity. Diagnosis and management of occiput posterior position remain a clinical challenge. This is partly caused by our inability to predict fetuses who will spontaneously rotate into occiput anterior from those who will have persistent occiput posterior position. The angle of progression, measured with transperineal ultrasound, represents a reliable tool for the evaluation of fetal head station during labor. The relationship between the persistence of occiput posterior position and fetal head station in the second stage of labor has not been previously assessed. This study aimed to evaluate the role of fetal head station, as measured by the angle of progression, in the prediction of persistent occiput posterior position and the mode of delivery in the second stage of labor. We recruited a nonconsecutive series of women with posterior occiput position diagnosed by transabdominal ultrasound in the second stage of labor. For each woman, a transperineal ultrasound was performed to measure the angle of progression at rest. We compared the angle of progression between women who delivered fetuses in occiput anterior position and those with persistent occiput posterior position at delivery. Receiver operating characteristics curves were performed to evaluate the accuracy of the angle of progression in the prediction of persistent occiput posterior position. Finally, we performed a multivariate logistic regression to determine independent predictors of persistent occiput posterior position. Overall, 63 women were included in the analysis. Among these, 39 women (62%) delivered in occiput anterior position, whereas 24 (38%) delivered in occiput posterior position (persistent occiput posterior position). The angle of progression was significantly narrower in the persistent occiput posterior position group than in women who delivered fetuses in occiput anterior position (118.3°±12.2° vs 127.5°±10.5°; P=.003). The area under the receiver operating characteristics curve was 0.731 (95% confidence interval, 0.594-0.869) with an estimated best cutoff range of 121.5° (sensitivity of 72% and specificity of 67%). On logistic regression analysis, the angle of progression was found to be independently associated with persistence of occiput posterior position (odds ratio, 0.942; 95% confidence interval, 0.889-0.998; P=.04). Finally, women who underwent cesarean delivery had significantly narrower angle of progression than women who had a vaginal delivery (113.5°±8.1 vs 128.0°±10.7; P<.001). The area under the receiver operating characteristics curve for the prediction of cesarean delivery was 0.866 (95% confidence interval, 0.761-0.972). At multivariable logistic regression analysis including the angle of progression, parity, and gestational age at delivery, the angle of progression was found to be the only independent predictor associated with cesarean delivery (odds ratio, 0.849; 95% confidence interval, 0.775-0.0930; P<.001). In fetuses with occiput posterior at the beginning of the second stage of labor, narrower values of the angle of progression are associated with higher rates of persistent occiput posterior position at delivery and a higher risk of cesarean delivery.

Persistent occiput posterior position outcomes following manual rotation: a randomized controlled trial

Persistent occiput posterior position in labor is associated with adverse maternal and perinatal outcomes. Prophylactic manual rotation from the occiput posterior position to the occiput anterior position in the second stage of labor is considered a safe and easy to perform procedure that in observational studies has shown promise as a method for preventing operative deliveries. This study aimed to determine the efficacy of prophylactic manual rotation in the management of occiput posterior position for preventing operative delivery. The hypothesis was that among women who are at least 37 weeks pregnant and whose baby is in the occiput posterior position early in the second stage of labor, manual rotation will reduce the rate of operative delivery compared with the "sham" rotation. A double-blinded, parallel, superiority, multicenter, randomized controlled clinical trial in 4 tertiary hospitals was conducted in Australia. A total of 254 nulliparous and parous women with a term pregnancy and a baby in the occiput posterior position in the second stage of labor were randomly assigned to receive either a prophylactic manual rotation (n=127) or a sham rotation (n=127). The primary outcome was operative delivery (cesarean, forceps, or vacuum delivery). Secondary outcomes were cesarean delivery, combined maternal mortality and serious morbidity, and combined perinatal mortality and serious morbidity. Analysis was by intention to treat. Proportions were compared using chi-square tests adjusted for stratification variables using the Mantel-Haenszel method or the Fisher exact test. Planned subgroup analyses by operator experience and by manual rotation technique (digital or whole-hand rotation) were performed. Operative delivery occurred in 79 of 127 women (62%) assigned to prophylactic manual rotation and 90 of 127 women (71%) assigned to sham rotation (common risk difference, 12; 95% confidence interval,-1.7 to 26; P=.09). Among more experienced operators or investigators, operative delivery occurred in 46 of 74 women (62%) assigned to manual rotation and 52 of 71 women (73%) assigned to a sham rotation (common risk difference, 18; 95% confidence interval,-0.5 to 36; P=.07). Cesarean delivery occurred in 22 of 127 women (17%) in both groups. Instrumental delivery (forceps or vacuum) occurred in 57 of 127 women (45%) assigned to prophylactic manual rotation and 68 of 127 women (54%) assigned to sham rotation (common risk difference, 10; 95% confidence interval,-3.1 to 22; P=.14). There was no significant difference in the combined maternal and perinatal outcomes. Prophylactic manual rotation did not result in a reduction in the rate of operative delivery. Given manual rotation was associated with a nonsignificant reduction in operative delivery, more randomized trials are needed, as our trial might have been underpowered. In addition, further research is required to further explore the potential impact of operator or investigator experience.

Predicting cesarean delivery for failure to progress as an outcome of labor induction in term singleton pregnancy

Induction of labor is one of the most common interventions in modern obstetrics, and its frequency is expected to continue to increase. There is inconsistency as to how failed induction of labor is defined; however, the majority of studies define success as the achievement of vaginal delivery. Induction of labor in nulliparous women poses an additional challenge with a 15% to 20% incidence of failure, ending in emergency operative deliveries. The Bishop score has been traditionally used before decisions for induction of labor. Nonetheless, it is subjective and prone to marked interobserver variation. Several studies have been conducted to find alternative predictors, yet a reliable, objective method still remains to be introduced and validated. Hence, there is still a need for the development of new predictive tools to facilitate informed decision making, optimization of resources, and minimization of potential risks of failure. Furthermore, a peripartum transperineal ultrasound scan has been proven to provide objective, noninvasive assessment of labor. This study aimed to assess the feasibility of developing and validating an objective and reproducible model for the prediction of cesarean delivery for failure to progress as an outcome of labor induction in term singleton pregnancies. This was a prospective observational cohort study conducted in Cairo University Hospitals and University of Bologna Hospitals between November 2018 and November 2019. We recruited 382 primigravidae with singleton term pregnancies in cephalic presentation. All patients had baseline Bishop scoring together with various transabdominal and transperineal ultrasound assessments of the fetus, maternal cervix, and pelvic floor. The managing obstetricians were blinded to the ultrasound scan findings. The method and indication of induction of labor, the total duration of stages of labor, mode of birth, and neonatal outcomes were all recorded. Women who had operative delivery for fetal distress or indications other than failure to progress in labor were excluded from the final analysis, leaving a total of 344 participants who were randomly divided into 243 and 101 pregnancies that constituted the model development and cross-validation groups, respectively. It was possible to perform transabdominal and transperineal scans and assess all the required parameters on all study participants. Univariate and multivariate analyses were used for selection of potential predictors and model fitting. The independent predictive variables for cesarean delivery included maternal age (odds ratio, 1.12; P=.003), cervical length (odds ratio, 1.08; P=.04), angle of progression at rest (odds ratio, 0.9; P=.001), and occiput posterior position (odds ratio, 5.7; P=.006). We tested the performance of the prediction model on our cross-validation group. The calculated areas under the curve for the ability of the model to predict cesarean delivery were 0.7969 (95% confidence interval, 0.71-0.87) and 0.88 (95% confidence interval, 0.79-0.97) for the developed and validated models, respectively. Maternal age and sonographic fetal occiput position, angle of progression at rest, and cervical length before labor induction are very good predictors of induction outcome in nulliparous women at term.

Sonographic confirmation of fetal position before operative vaginal delivery should be recommended in clinical guidelines

Sonographic confirmation of fetal position before operative vaginal delivery should be recommended in clinical guidelines

Clinical Effect of Hand Rotation of Fetal Head in Treatment of Occipitotransverse Position and Occipitoposterior Position in Difficult Labour

Clinical Effect of Hand Rotation of Fetal Head in Treatment of Occipitotransverse Position and Occipitoposterior Position in Difficult Labour

When does fetal head rotation occur in spontaneous labor at term: results of an ultrasound-based longitudinal study in nulliparous women

Improved information about the evolution of fetal head rotation during labor is required. Ultrasound methods have the potential to provide reliable new knowledge about fetal head position. The aim of the study was to describe fetal head rotation in women in spontaneous labor at term using ultrasound longitudinally throughout the active phase. This was a single center, prospective cohort study at Landspitali - The National University Hospital of Iceland, Reykjavík, Iceland, from January 2016 to April 2018. Nulliparous women with a single fetus in cephalic presentation and spontaneous labor onset at ≥37 weeks' gestation were eligible. Inclusion occurred when the active phase could be clinically established by labor ward staff. Cervical dilatation was clinically examined. Fetal head position and subsequent rotation were determined using both transabdominal and transperineal ultrasound. Occiput positions were marked on a clockface graph with 24 half-hour divisions and categorized into occiput anterior (≥10- and ≤2-o'clock positions), left occiput transverse (>2- and <4-o'clock positions), occiput posterior (≥4- and ≤8 o'clock positions), and right occiput transverse positions (>8- and <10-o'clock positions). Head descent was measured with ultrasound as head-perineum distance and angle of progression. Clinical vaginal and ultrasound examinations were performed by separate examiners not revealing the results to each other. We followed the fetal head rotation relative to the initial position in the pelvis in 99 women, of whom 75 delivered spontaneously, 16 with instrumental assistance, and 8 needed cesarean delivery. At inclusion, the cervix was dilated 4 cm in 26 women, 5 cm in 30 women, and ≥6 cm in 43 women. Furthermore, 4 women were examined once, 93 women twice, 60 women 3 times, 47 women 4 times, 20 women 5 times, 15 women 6 times, and 3 women 8 times. Occiput posterior was the most frequent position at the first examination (52 of 99), but of those classified as posterior, most were at 4- or 8-o'clock position. Occiput posterior positions persisted in >50% of cases throughout the first stage of labor but were anterior in 53 of 80 women (66%) examined by and after full dilatation. The occiput position was anterior in 75% of cases at a head-perineum distance of ≤30 mm and in 73% of cases at an angle of progression of ≥125° (corresponding to a clinical station of+1). All initial occiput anterior (19), 77% of occiput posterior (40 of 52), and 93% of occiput transverse positions (26 of 28) were thereafter delivered in an occiput anterior position. In 6 cases, the fetal head had rotated over the 6-o'clock position from an occiput posterior or transverse position, resulting in a rotation of >180°. In addition, 6 of the 8 women ending with cesarean delivery had the fetus in occiput posterior position throughout the active phase of labor. We investigated the rotation of the fetal head in the active phase of labor in nulliparous women in spontaneous labor at term, using ultrasound to provide accurate and objective results. The occiput posterior position was the most common fetal position throughout the active phase of the first stage of labor. Occiput anterior only became the most frequent position at full dilatation and after the head had descended below the midpelvic plane.

Fetal descent in nulliparous women assessed by ultrasound: a longitudinal study

Ultrasound measurements offer objective and reproducible methods to measure the fetal head station. Before these methods can be applied to assess labor progression, the fetal head descent needs to be evaluated longitudinally in well-defined populations and compared with the existing data derived from clinical examinations. This study aimed to use ultrasound measurements to describe the fetal head descent longitudinally as labor progressed through the active phase in nulliparous women with spontaneous onset of labor. This was a single center, prospective cohort study at the Landspitali - The National University Hospital of Iceland, Reykjavik, Iceland, from January 2016 to April 2018. Nulliparous women with a single fetus in cephalic presentation and spontaneous labor onset at a gestational age of ≥37 weeks, were eligible. Participant inclusion occurred during admission for women with an established active phase of labor or at the start of the active phase for women admitted during the latent phase. The active phase was defined as an effaced cervix dilated to at least 4 cm in women with regular contractions. According to the clinical protocol, vaginal examinations were done at entry and subsequently throughout labor, paired each time with a transperineal ultrasound examination by a separate examiner, with both examiners being blinded to the other's results. The measurements used to assess the fetal head station were the head-perineum distance and angle of progression. Cervical dilatation was examined clinically. The study population comprised 99 women. The labor patterns for the head-perineum distance, angle of progression, and cervical dilatation differentiated the participants into 75 with spontaneous deliveries, 16 with instrumental vaginal deliveries, and 8 cesarean deliveries. At the inclusion stage, the cervix was dilated 4 cm in 26 of the women, 5 cm in 30 of the women, and ≥6 cm in 43 women. One cesarean and 1 ventouse delivery were performed for fetal distress, whereas the remaining cesarean deliveries were conducted because of a failure to progress. The total number of examinations conducted throughout the study was 345, with an average of 3.6 per woman. The ultrasound-measured fetal head station both at the first and last examination were associated with the delivery mode and remaining time of labor. In spontaneous deliveries, rapid head descent started around 4 hours before birth, the descent being more gradual in instrumental deliveries and absent in cesarean deliveries. A head-perineum distance of 30 mm and angle of progression of 125° separately predicted delivery within 3.0 hours (95% confidence interval, 2.5-3.8 hours and 2.4-3.7 hours, respectively) in women delivering vaginally. Although the head-perineum distance and angle of progression are independent methods, both methods gave similar mirror image patterns. The fetal head station at the first examination was highest for the fetuses in occiput posterior position, but the pattern of rapid descent was similar for all initial positions in spontaneously delivering women. Oxytocin augmentation was used in 41% of women; in these labors a slower descent was noted. Descent was only slightly slower in the 62% of women who received epidural analgesia. A nonlinear relationship was observed between the fetal head station and dilatation. We have established the ultrasound-measured descent patterns for nulliparous women in spontaneous labor. The patterns resemble previously published patterns based on clinical vaginal examinations. The ultrasound-measured fetal head station was associated with the delivery mode and remaining time of labor.

VP58.03: The role of the angle of progression in the prediction of the outcome of occiput posterior position in the second stage of labour

VP58.03: The role of the angle of progression in the prediction of the outcome of occiput posterior position in the second stage of labour