The "occiput-spine angle": a new sonographic index of fetal head deflexion during the first stage of labor.

Fetal head "attitude" (relationship of fetal head to spine) in the first stage of labor may have a substantial impact on labor outcome. The diagnosis of fetal head deflexion traditionally is based on digital examination in labor, although the use of ultrasound to support clinical diagnosis has been recently reported. The aims of this study were: (1) to quantify the degree of fetal head deflection via the use of sonography during the first stage of labor; and (2) to determine whether a parameter derived from ultrasound examination (the occiput-spine angle) has a relationship with the course and outcome of labor. This was a prospective multicentric, cross-sectional study conducted at the Maternity Unit of the University of Bologna and Parma from January 2014 to April 2015. A nonconsecutive series of women with uncomplicated singleton pregnancies at term gestation (37 weeks or more) were submitted to transabdominal ultrasound during the first stage of labor. If fetal position was occiput anterior or transverse, the angle between the fetal occiput and the cervical spine (the occiput-spine angle) was sonographically obtained on the sagittal plane. The measurements of the occiput spine-angle were performed offline by 2 operators who were blinded to the labor outcome. The intra- and interobserver reproducibility and the correlation between the occiput-spine angle and the mode of delivery were evaluated. A total of 108 pregnant women were recruited, 79 of which underwent a spontaneous vaginal delivery and 29 were submitted to obstetric intervention (19 cesarean delivery and 10 instrumental vaginal deliveries). The mean value of the occiput-spine angle measured in the active phase of the first stage was 126° ± 9.8° (SD). The occiput-spine angle measurement showed a very good intraobserver (r = 0.86; 95% confidence interval [95% CI] 0.80-0.90) and a fair-to-good interobserver (r = 0.64; 95% CI 0.51-0.74) agreement. The occiput-spine angle was significantly narrower in women who underwent obstetric intervention (cesarean or vacuum delivery) due to labor arrest (121° ± 10.5° vs 127° ± 9.4°, P = .03). Multivariable logistic regression analysis showed that narrow occiput-spine angle values (OR 1.08; 95% CI 1.00-1.16; P = .04) and nulliparity (OR 16.06; 95% CI 1.71-150.65; P = .02) were independent risk factors for operative delivery. A larger occiput-spine angle width (i.e., >125°) showed to be significantly associated with a shorter duration of labor (hazard ratio = 1.62; 95% CI 1.07-2.45; P = .02). We described herein the "occiput-spine angle," a new sonographic parameter to assess fetal head deflection during labor. Fetuses with smaller occiput-spine angle (<125°) are at increased risk for operative delivery.

Ghi T ，Bellussi F ，Azzarone C ，Krsmanovic J ，Franchi L ，Youssef A ，Lenzi J ，Fantini MP ，Frusca T ，Pilu G ... -  《-》

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

Dall'Asta A ，Rizzo G ，Masturzo B ，Di Pasquo E ，Schera GBL ，Morganelli G ，Ramirez Zegarra R ，Maqina P ，Mappa I ，Parpinel G ，Attini R ，Roletti E ，Menato G ，Frusca T ，Ghi T ... -  《-》

Sonographic diagnosis of fetal head deflexion and the risk of cesarean delivery.

Malpositions and deflexed cephalic malpresentations are well recognized causes of dysfunctional labor, may result in fetal and maternal complications, and are diagnosed more precisely with an ultrasound examination than with a digital examination. This study aimed to assess the incidence of malpositions and deflexed cephalic malpresentations at the beginning of the second stage of labor and to evaluate the role of the sonographic diagnosis of deflexion in the prediction of the mode of delivery. Women in labor with a singleton pregnancy at term with fetuses in a cephalic presentation at 10 cm of cervical dilatation were prospectively examined. A transabdominal ultrasound was performed to assess the fetal head position by demonstrating the fetal occiput or the eyes. Deflexion was assessed by the measurement of the occiput-spine angle when the occiput was anterior or transverse and by qualitative assessment of the relationship between chin and thorax when the occiput was posterior. Transperineal ultrasound was performed in occiput posterior fetuses to discriminate between sinciput, brow, and face presentation. Maternal, labor, and neonatal parameters including maternal age, induction of labor, use of epidural, birthweight, arterial pH, and neonatal intensive care unit admission were recorded. Patients were divided into 2 groups according to the sonographic diagnosis of head deflexion. Adjusted odds ratios were calculated using multivariate logistic regression to determine the association between cesarean delivery and the 2 groups. In addition, labor and neonatal characteristics were compared between occiput anterior and occiput posterior-occiput transverse fetuses. Of the 200 women at the beginning of the second stage, the fetus was in occiput anterior position in 156 (78%), transverse in 11 (5.5%), and posterior in 33 (16.5%) cases. Deflexion was diagnosed in 33 of 156 (21.2%) occiput anterior fetuses and 19 of 44 (43.2%) occiput posterior and occiput transverse fetuses. Cesarean deliveries were significantly associated with fetal head deflexion both in occiput anterior (P=.001) and occiput posterior (P<.001) fetuses. Sonographic diagnosis of fetal head deflexion was an independent risk factor for cesarean delivery both in occiput anterior (adjusted odds ratio, 5.37; 95% confidence interval, 1.819-15.869) and occiput posterior (adjusted odds ratio, 13.9; 95% confidence interval, 1.958-98.671) cases, and it was an independent risk factor for cesarean delivery regardless of the occiput position (adjusted odds ratio, 5.83; 95% confidence interval, 2.47-13.73). The sonographic diagnosis of fetal head deflexion at the beginning of the second stage increases the risk of cesarean delivery.

Bellussi F ，Livi A ，Cataneo I ，Salsi G ，Lenzi J ，Pilu G ... -  《-》

Measurement of the fetal occiput-spine angle during the first stage of labor as predictor of the progress and outcome of labor.

Maged AM ，Soliman EM ，Abdellatif AA ，Nabil M ，Said OI ，Mohesen MN ，Raslan AN ，Elbaradie SMY ... -  《-》

Prediction of spontaneous vaginal delivery in nulliparous women with a prolonged second stage of labor: the value of intrapartum ultrasound.

A limited number of studies have addressed the role of intrapartum ultrasound in the prediction of the mode of delivery in women with prolonged second stage of labor. The objective of the study was to evaluate the role of transabdominal and transperineal sonographic findings in the prediction of spontaneous vaginal delivery among nulliparous women with prolonged second stage of labor. This was a 2-center prospective study conducted at 2 tertiary maternity units. Nulliparous women with a prolonged active second stage of labor, as defined by active pushing lasting more than 120 minutes, were eligible for inclusion. Transabdominal ultrasound to evaluate the fetal head position and transperineal ultrasound for the measurement of the midline angle, the head-perineum distance, and the head-symphysis distance were performed in between uterine contractions and maternal pushes. At transperineal ultrasound the angle of progression was measured at rest and at the peak of maternal pushing effort. The delta angle of progression was defined as the difference between the angle of progression measured during active pushing at the peak of maternal effort and the angle of progression at rest. The sonographic findings of women who had spontaneous vaginal delivery vs those who required obstetric intervention, either vacuum extraction or cesarean delivery, were evaluated and compared. Overall, 109 were women included. Spontaneous vaginal delivery and obstetric intervention were recorded in 40 (36.7%) and 69 (63.3%) patients, respectively. Spontaneous vaginal delivery was associated with a higher rate of occiput anterior position (90% vs 53.2%, P < .0001), lower head-perineum distance and head-symphysis distance (33.2 ± 7.8 mm vs 40.1 ± 9.5 mm, P = .001, and 13.1 ± 4.6 mm vs 19.5 ± 8.4 mm, P < .001, respectively), narrower midline angle (29.6° ± 15.3° vs 54.2° ± 23.6°, P < .001) and wider angle of progression at the acme of the pushing effort (153.3° ± 19.8° vs 141.8° ± 25.7°, P = .02) and delta-angle of progression (17.3° ± 12.9° vs 12.5° ± 11.0°, P = .04). At logistic regression analysis, only the midline angle and the head-symphysis distance proved to be independent predictors of spontaneous vaginal delivery. More specifically, the area under the curve for the prediction of spontaneous vaginal delivery was 0.80, 95% confidence interval (0.69-0.92), P < .001, and 0.74, 95% confidence interval (0.65-0.83), P = .002, for the midline angle and for the head-symphysis distance, respectively. Transabdominal and transperineal intrapartum ultrasound parameters can predict the likelihood of spontaneous vaginal delivery in nulliparous women with prolonged second stage of labor.

Dall'Asta A ，Angeli L ，Masturzo B ，Volpe N ，Schera GBL ，Di Pasquo E ，Girlando F ，Attini R ，Menato G ，Frusca T ，Ghi T ... -  《-》