Fetal Head Station Research Articles

Unintended Upper Uterine Wall Extensions at the Time of Cesarean Delivery: Risk Factors and Associated Adverse Maternal and Neonatal Outcomes.

This study aims to estimate the frequency of unintended upper uterine wall extensions during cesarean delivery (CD) and identify associated risk factors and adverse outcomes. A multicenter retrospective cohort study was conducted, including patients who underwent CD between 2005 and 2021. Demographic factors, obstetric history, CD indications, delivery and surgical characteristics, adverse maternal and neonatal outcomes were compared between those with unintended upper uterine wall extensions during CD and those without extensions. Crude and adjusted estimates (odds ratios [ORs] and 95% confidence intervals [CIs]) were used. Among 30,517 patients meeting inclusion criteria, 117 (0.4%) had an unintended upper uterine wall extension. In univariate analysis, upper uterine wall extensions were associated with higher rates of intrapartum CD, second-stage CD, unplanned or emergency CD, CD following failed vacuum delivery or trial of labor after CD, chorioamnionitis, prolonged labor, increased vaginal exams, lower fetal head station, and higher birth weight. During surgery, higher rates of general anesthesia, significant intraperitoneal adhesion, fetal malpresentation, and fetal extraction by the leg were observed. Multivariable analysis identified fetal extraction not by head (adjusted OR [aOR]: 9.17, 95% CI: 5.35-15.73), vertex fetal presentation (aOR: 3.65, 95% CI: 1.81-7.35), second-stage CD (aOR: 3.07, 95% CI: 1.24-7.59), and trial of labor after cesarean (aOR: 2.04, 95% CI: 1.08-3.84) as significant risk factors for unintended upper uterine wall extensions. Additionally, upper uterine wall extensions were associated with higher rates of maternal and neonatal complications, including longer operating times, excessive bleeding, postpartum hemorrhage, intraperitoneal drainage, blood product transfusion, puerperal fever, paralytic ileus, Apgar score < 7 at 1 and 5 minutes, and fetal intracranial hemorrhage. Our study identifies risk factors for unintended upper uterine wall extensions during CD. While these extensions are infrequent, their occurrence is associated with increased maternal and neonatal morbidity. · Unintended upper uterine wall extensions occur in 0.4% of cesarean deliveries.. · Significant risk factors include fetal extraction not by head and second-stage CD.. · Extensions are associated with increased maternal complications like excessive bleeding and prolonged surgery.. · Neonatal complications include lower Apgar scores and intracranial hemorrhage.. · Awareness of these risks is critical for improving cesarean delivery outcomes..

Determinants of Higher Oxytocin Dose Need During Labor Induction

Background: Several guidelines have been published regarding intrapartum oxytocin infusion for labor induction or augmentation; however, many of them lack specificity. Objectives: Therefore, this study aimed to assess the oxytocin dose administered during labor and evaluate its association with maternal characteristics and short-term perinatal outcomes. Methods: This retrospective cross-sectional study was conducted on 162 term pregnant women who were admitted to the labor ward for vaginal delivery in two academic hospitals during 2021 - 2022. Maternal demographic features, obstetric and medical history data, labor process details (initial Bishop score, membrane status on admission and at the time of labor induction or augmentation, latent and active phase duration, oxytocin dose, delivery mode, and neonatal outcomes) were obtained and recorded. Participants were divided into two main groups based on the intrapartum oxytocin dose, and the desired outcomes were reported and compared between the groups. Results: The median maternal age was 28 years (range: 16 - 46). The median oxytocin dose administered during labor induction was 10 mU/min (range: 2.5 - 25 mU/min). Oxytocin dose was significantly correlated with gestational age (P &lt; 0.001), cervical dilation and effacement (P &lt; 0.001), fetal head station (P &lt; 0.001), cervical consistency (P &lt; 0.001), and cervical Bishop score before labor induction (P &lt; 0.001). The cervical dilation at the time of membrane rupture was also positively correlated with the intrapartum oxytocin dose (P = 0.013). Higher gestational age was correlated with a higher required oxytocin dose (P &lt; 0.001). The cesarean rate was 22.8% in the study population, and it was positively correlated with intrapartum oxytocin dose (P &lt; 0.001). Conclusions: The cervical Bishop score and its components, except for cervical position, were correlated with the intrapartum oxytocin dose. In other words, the less favorable the cervix, the higher the likelihood of requiring higher doses of oxytocin and consequently experiencing a longer duration of labor. Additionally, the cesarean rate was higher in those who needed oxytocin doses of more than 10 mU/min; however, short - term neonatal outcomes were not different.

Assessment of fetal head station with transperineal ultrasound: automatic approach versus expert operator evaluation

Assessment of fetal head station with transperineal ultrasound: automatic approach versus expert operator evaluation

Investigating the accuracy of Johnson’s rule in estimating fetal weight

BACKGROUND: Birth weight has a significant impact on perinatal mortality. Therefore, the estimation of fetal weight greatly influences the policies necessary for care during and after delivery. We aimed to investigate Johnson’s rule in estimating fetal weight. MATERIALS AND METHOD: This study was a single-group longitudinal study that was conducted in 6 months from October 2021 to April 2022 on 150 pregnant women in Isfahan-Iran. The sampling method was accessible. Inclusion criteria include being term, singleton, without abnormality, intact membranes, cephalic presentation, and exclusion criteria include diagnosed polyhydramnios or oligohydramnios and mother’s abdominal or pelvic known masses. After completing the informed consent, fetal weight was estimated by Johnson’s rule and was compared with the birth weight. Descriptive and analytical statistics (mean-standard deviation (SD), number-percentage, t-paired, and Spearman’s correlation coefficient) were used to achieve the objectives of the study. The receiver operating characteristic (ROC) curve was also used to determine the sensitivity, specificity, and positive and negative predictive value of Johnson’s law. RESULT: The mean (SD) birth weight was 3032.88 ± 481.11 g and the mean (SD) estimated fetal weight (EFW) by the clinical method was 3152.15 ± 391.95 g. There was a significant difference between the averages (P &lt; 0.001). The percentage error of EFW showed a significant negative correlation (r = -0.286; P &lt; 0.05) with gestational age (GA) and a significant positive correlation (r = 0.263; P &lt; 0.05) with the fetal head station. The sensitivity and specificity of EFW with Johnson’s rule, in normal fetal birth weight, were higher than in low birth weight fetal. The accuracy of EFW with ± 10% of the actual weight was higher in average for gestational age (AGA) (84.3%) and high-for-gestational-age (LGA) (70%) than in low-for-gestational-age (SGA) (4%). The EFW mean percentage error in SGA was higher than in the other two weight groups. This method, especially for AGA and LGA fetuses, can be a suitable alternative to other weight estimation methods. CONCLUSION: Clinical estimation of weight via Johnson’s rule due to availability and no cost can be a suitable method for managing childbirth based on fetal weight.

Does transperineal ultrasound predict the risk of perineal trauma in women with term pregnancy? A prospective observational study.

This study was conducted to evaluate the prevalence of perineal trauma during childbirth and to assess the correlations of the pelvic floor dimensions and fetal head station with obstetric trauma in a prospectively recruited cohort of women. The study included women with a gestational age of at least 37 weeks, who were carrying a single fetus in a cephalic presentation. Transperineal ultrasound (TPU) was performed prior to the onset of labor or labor induction. The purpose was to measure the anteroposterior diameter (APD) of the levator ani muscle (LAM) and the angle of progression, at both rest and maximum Valsalva maneuver. The head-perineum distance was assessed only at rest. A total of 296 women were included. Of the 253 women who delivered vaginally, 19% (48/253) experienced no perineal trauma, 18.2% (46/253) received an episiotomy during childbirth, 34.4% (87/253) sustained a first-degree laceration, 25.3% (64/253) had a second-degree laceration, and 3.2% had a third- or fourth-degree laceration (8/253). Women with episiotomy had a significantly shorter median APD under Valsalva than women without perineal trauma. Furthermore, women with LAM coactivation (identified by a negative difference between the APD at Valsalva and the APD at rest) were approximately three times more likely to undergo an operative vaginal delivery and over five times more likely to sustain a third- or fourth-degree tear during childbirth than women who exhibited normal relaxation of the LAM during the Valsalva maneuver. TPU may predict the risk of perineal trauma in women with term pregnancy during childbirth.

The Association between Fetal Head Station at the First Diagnosis of the Second Stage of Labor and Delivery Outcomes

The Association between Fetal Head Station at the First Diagnosis of the Second Stage of Labor and Delivery Outcomes

Fetal Head Station in Active Phase of Labour in Nullipara: Study at a Tertiary Care Centre

Fetal Head Station in Active Phase of Labour in Nullipara: Study at a Tertiary Care Centre

The success of vaginal birth by use of trans-labial ultrasound plus vaginal examination and vaginal examination only in pregnant women with labor induction: a comparative study

BackgroundPredicting the success of vaginal delivery is an important issue in preventing adverse maternal and neonatal outcomes. Thus, this study aimed to compare the success rate of vaginal birth by using trans-labial ultrasound and vaginal examination, and vaginal examination only in pregnant women with labor induction.MethodsThis was a comparative study including 392 eligible pregnant women with labor induction attending to a teaching hospital affiliated with Iran University of Medical Sciences from April to October 2018 in Tehran, Iran. Women were randomly assigned to two groups; the trans-labial ultrasound plus vaginal examination (group A), and the vaginal examination only (group B). Women were included in the study if they satisfied the following criteria: singleton pregnancy, 37 to 42 weeks of gestational age, fetal head presentation, a living fetus with no abnormalities, uncomplicated pregnancy, and no previous cesarean section or any uterine surgery. We used a partograph for both groups to assess the fetal head position and the fetal head station. In group 1, the Angle of Progression (AoP) and Rotation Angle (RA) were also assessed. Finally, the success and progression of vaginal delivery in two groups were compared by predicting the duration of delivery and mode of delivery.ResultsThe findings showed that 8.68% of women in the trans-labial plus vaginal examination group delivered by cesarean section, while 6.13% in the vaginal examination only group delivered by cesarean section (P = 0.55). In women with cesarean section in positive fetal head stations, Angle of Progression (AoP) was significantly decreased ranging from 90 to 135 degrees compared to women who delivered vaginally (135–180 degrees; P < 0.001). In addition, the Rotation Angle (RA) was significantly decreased in women with cesarean section ranging from 0 to 30 degrees compared to women who delivered vaginally (60-90degrees; P < 0.001). Further analysis indicated that a higher risk of cesarean section was associated with vaginal examination only as compared to trans-labial ultrasound plus vaginal examination (HR: 8.65, P < 0.001).ConclusionAngle of Progression (AoP) and Rotation Angle (RA) indexes might be useful parameters to predict labor progression and successful vaginal delivery among women undergoing labor induction.

A framework for computing angle of progression from transperineal ultrasound images for evaluating fetal head descent using a novel double branch network.

Background: Accurate assessment of fetal descent by monitoring the fetal head (FH) station remains a clinical challenge in guiding obstetric management. Angle of progression (AoP) has been suggested to be a reliable and reproducible parameter for the assessment of FH descent. Methods: A novel framework, including image segmentation, target fitting and AoP calculation, is proposed for evaluating fetal descent. For image segmentation, this study presents a novel double branch segmentation network (DBSN), which consists of two parts: an encoding part receives image input, and a decoding part composed of deformable convolutional blocks and ordinary convolutional blocks. The decoding part includes the lower and upper branches, and the feature map of the lower branch is used as the input of the upper branch to assist the upper branch in decoding after being constrained by the attention gate (AG). Given an original transperineal ultrasound (TPU) image, areas of the pubic symphysis (PS) and FH are firstly segmented using the proposed DBSN, the ellipse contours of segmented regions are secondly fitted with the least square method, and three endpoints are finally determined for calculating AoP. Results: Our private dataset with 313 transperineal ultrasound (TPU) images was used for model evaluation with 5-fold cross-validation. The proposed method achieves the highest Dice coefficient (93.4%), the smallest Average Surface Distance (6.268 pixels) and the lowest AoP difference (5.993°) by comparing four state-of-the-art methods. Similar results (Dice coefficient: 91.7%, Average Surface Distance: 7.729 pixels: AoP difference: 5.110°) were obtained on a public dataset with >3,700 TPU images for evaluating its generalization performance. Conclusion: The proposed framework may be used for the automatic measurement of AoP with high accuracy and generalization performance. However, its clinical availability needs to be further evaluated.

Head-to-perineum distance measured transperineally as a predictor of failed midcavity vacuum-assisted delivery

During the second stage of labor, in case of a need for a fetal extraction at midcavity, the choice of attempting the procedure between operative vaginal delivery and cesarean delivery is difficult. Moreover, guidelines on this subject are not clear. This study aimed to identify antenatal and intrapartum parameters associated with a failed midcavity vacuum-assisted delivery and its association with maternal and neonatal adverse outcomes. This was a single-center, retrospective, cohort study conducted at a tertiary maternity hospital in France from January 2010 to December 2020. Women with singleton pregnancies under epidural analgesia with nonanomalous cephalic presenting fetuses and gestational ages at ≥37 weeks of gestation, who were submitted to midcavity vacuum-assisted delivery, were included. Following the American College of Obstetricians and Gynecologists definition, midcavity was defined as the presenting part of the fetus (ie, the fetal head) found at stations 0 and +1. For research purposes, all patients were submitted to transperineal ultrasound to evaluate the head-to-perineum distance, however, this measurement did not affect the decision to perform a midcavity vacuum-assisted delivery. The primary outcome of the study was failed midcavity vacuum-assisted delivery leading to cesarean delivery or the use of a different instrument to achieve vaginal delivery. Overall, 951 cases of midcavity vacuum-assisted delivery were included in this study. Failed midcavity vacuum-assisted delivery occurred in 242 patients (25.4%). Factors independently associated with failed midcavity vacuum-assisted delivery included maternal height (adjusted odds ratio, 0.96; 95% confidence interval, 0.94-0.99; P=.002), duration of the active phase of the first stage of labor (adjusted odds ratio, 1.11; 95% confidence interval, 1.05-1.17; P<.001), nonocciput anterior fetal head position (adjusted odds ratio, 1.47; 95% confidence interval, 1.06-2.04; P=.02), z score of the head-to-perineum distance (adjusted odds ratio, 1.23; 95% confidence interval, 1.05-1.43; P=.01), and birthweight of >4000 g (adjusted odds ratio, 2.04; 95% confidence interval, 1.28-3.26; P=.003). Women submitted to a failed midcavity vacuum-assisted delivery were more likely to have a major postpartum hemorrhage (7.1% vs 2.0%; P<.001), whereas neonates were more likely to have an umbilical artery pH of <7.1 (30.5% vs 19.8%; P=.001), be admitted to the neonatal intensive care unit (9.6% vs 4.7%; P=.005), and have a severe caput succedaneum (14.9% vs 0.7%; P<.001). Subgroup analysis on all patients with a fetal head station of 0 found that the head-to-perineum distance was the only independent variable associated with failed midcavity vacuum-assisted delivery (adjusted odds ratio, 1.66; 95% confidence interval, 1.29-2.12; P<.001). The area under the receiving operating characteristic curve of the head-to-perineum distance in this subgroup population was 0.67 (95% confidence interval, 0.60-0.73; P<.001), and the optimal cutoff point of the head-to-perineum distance measurement discriminating between failed and successful midcavity vacuum-assisted deliveries was 55 mm. It was associated with a 0.90 (95% confidence interval, 0.83-0.95) sensitivity, 0.19 (95% confidence interval, 0.14-0.25) specificity, 0.36 (95% confidence interval, 0.30-0.42) positive predictive value, and 0.80 (95% confidence interval, 0.66-0.90) negative predictive value. Study data showed that a high fetal head station, measured using the head-to-perineum distance, and a nonocciput anterior position of the fetal head are independently associated with failed midcavity vacuum-assisted delivery. The result supported the systematic assessment of the sonographic head station and position before performing a midcavity vacuum-assisted delivery.

Outcome of Unengaged Fetal Head at Term in Nullipara

Introduction: Engagement of fetal head is usually regarded as a phenomenon of labor in nullipara. It commonly occurs during the last few weeks in nullipara, in majority by 38 weeks or even during the first stage of labor. The aim of this study was to determine the outcome of unengaged fetal head at term in nullipara. Materials And Methods: This study was conducted at obstetrics and gynecology unit, tertiary care teaching hospital, Peshawar. This was a descriptive cross-sectional study which was conducted during 12th Jan 2021 to 10th April 2022, in which a total of 111 patients were included in the study using 16.89% proportion of caesarean section¸95% confidence level and 7% margin of error under WHO software for sample size determination. Results: In this study, patients were in age range 19-35 years and heights of the patients were 140-160cm. Among 111 patients, normal vaginal delivery occurred in 71.71% patients, instrumental delivery in 10.8% and 18.2% patients underwent low segment caesarean section. Total number of nullipara with unengaged head were divided into four groups based on fetal head station in early labor. Total number of nullipare in each group of which 30.6% were free head, 43.2% at -3 station group, 21.62%-2 station group and 45% in -1 group Practical implication in nulliparous patients a high station at the onset of labour is not necessarily an omnious finding, even though the incidence of arrest disorders are higher when station is -3,or floating ,obstetricians can still be optimistic towards vaginal delivery. Conclusions: Nullipara with unengaged head at term during labors should be regarded with suspicion and as such should be regarded with apprehension in labor. Dysfunctional labor occurs in only small proportion of patients with unengaged head. It is concluded that the incidence of active surgical intervention in nullipara with unengaged fetal head at term is quite high. Keywords: Primigravidae, engagement of head, delivery, LSCS, Head station.

Head position and vacuum-assisted delivery using the Kiwi Omnicup.

To evaluate the association between fetal head position during prevacuum assessment and adverse outcomes. This retrospective cohort study included all vacuum-assisted deliveries using the Kiwi Omnicup over 5 years. Primary outcomes were third- or fourth-degree perineal tear, pH < 7.1, and subgaleal hematoma (SGH). AGAR, neonatal intensive care unit admission, cephalohematoma, Erb's palsy, third-stage duration, and postpartum hemorrhage were secondary. Outcomes were compared between the occiput posterior (OP) and occiput anterior (OA) positions. The study included 1960 patients. OP position was more likely to involve epidural analgesia (311 [82.5%] vs. 1216 [77%], P= 0.020), higher fetal head station (P= 0.001), higher percentage of cup detachments (121 cases [32.1%] vs. 307 [19.4%], P= 0.001), and longer procedure (5.5 ± 3.7 min vs. 4.7 ± 2.8 min, P= 0.001). OP was associated with umbilical cord pH< 7.1 (21 [5.5%] vs. 52 [3.9%], P= 0.032), NICU admissions (16 [4.2%] vs. 38 [2.4%], P= 0.049), SGH (18 [4.8%] vs. 38 [2.4%], P= 0.013), and high-degree perineal tears (12 [3.2%] vs. 26 [1.7%], with borderline significance, P= 0.051). SGH and high-grade tears remained significantly associated with OP position (P= 0.008 and P= 0.016, respectively) after adjusting for maternal age, nulliparity, diabetes, epidural anesthesia, preprocedure head station, and birth weight. OP position is an independent risk-factor for anal sphincter injury and SGH during vacuum-assisted delivery.

Ultrasound in labor: clinical practice guideline recommendation by the World Association of Perinatal Medicine (WAPM) and the Perinatal Medicine Foundation (PMF)

This recommendation document follows the mission of the World Association of Perinatal Medicine (WAPM) in collaboration with the Perinatal Medicine Foundation (PMF). We aim to bring together groups and individuals throughout the world for standardization to implement the ultrasound evaluation in labor ward and improve the clinical management of labor. Ultrasound in labor can be performed using a transabdominal or a transperineal approach depending upon which parameters are being assessed. During transabdominal imaging, fetal anatomy, presentation, liquor volume, and placental localization can be determined. The transperineal images depict images of the fetal head in which calculations to determine a proposed fetal head station can be made.

The Value of Fetal Head Station as a Delivery Mode Predictor in Primiparous Women at Term before the Onset of Labor

Objective: Our objective was to demonstrate the role of the clinical determination of fetal head station (FHS) at term to predict the delivery mode in primiparous women before the onset of labor. Methods: This prospective study included unselected primiparous women at term who presented at our tertiary maternity. We excluded multiparous patients, pregnancies with a planned Cesarean section, non-cephalic presentations, and multiple pregnancies. The protocol included weekly clinical examinations to assess the FHS. The results were used to describe the clinical fetal head descent at term. We correlated the fetal head station determinations at each week with labor outcome, including the evaluations performed within the week before delivery. Results: The data show no significant differences between vaginal (VD) and Cesarean section delivery (CS) cases regarding FHS determined at each week at term. The median determinations at the gestational ages (GW) from 37 to 41 were −2 and −3, similar between the two groups, with a more consistent difference at 41 GW: station -1 for VD compared to −3 for CS. There were significant differences between the “week before delivery” evaluations of the two groups. The determinations showed for both groups similar minimum (−5), maximum (+1), and median (−2) FHS values. Most vaginal deliveries cases presented at weekly examinations with increasing rates toward more advanced stations: from 10% at station −4 to 35% at station −1. Although we investigated a low-risk group, we found significant differences between the vaginal and Cesarean groups in terms of age, weight, and BMI. We provided a multiple logistic regression equation that considered the predictive clinical variables at term: the fetal head situation, age, weight, height, and BMI. Conclusion: The clinical evaluation of fetal head station in primiparous before labor onset has a limited value regarding the prediction of the delivery mode. There is a potential benefit for the determinations performed within the week before delivery, but such a policy would require weekly assessments of the FHS at term, which is unlikely to be implemented. Another potential benefit would involve estimating labor outcomes in late-term or prolonged pregnancy. The fine tuning of the logistic prediction should be achieved by increasing the studied population and the number of centers involved before counseling primiparous women at term based on the clinical fetal engagement data.

Ultrasound in labor: clinical practice guideline and recommendation by the WAPM-World Association of Perinatal Medicine and the PMF-Perinatal Medicine Foundation.

This recommendation document follows the mission of the World Association of Perinatal Medicine in collaboration with the Perinatal Medicine Foundation. We aim to bring together groups and individuals throughout the world for standardization to implement the ultrasound evaluation in labor ward and improve the clinical management of labor. Ultrasound in labor can be performed using a transabdominal or a transperineal approach depending upon which parameters are being assessed. During transabdominal imaging, fetal anatomy, presentation, liquor volume, and placental localization can be determined. The transperineal images depict images of the fetal head in which calculations to determine a proposed fetal head station can be made.

Intrapartum ultrasound use in clinical practice as a predictor of delivery mode during prolonged second stage of labor.

To determine the validity of intrapartum ultrasound (IPUS), and particularly the angle of progression (AOP), in predicting delivery mode when measured in real-life clinical practice among women with protracted second stages of labor. Using electronic medical records, nulliparous women with a second stage of labor of ≥ 3h ("prolonged") and a documented AOP measurement during the second stage were identified. The ability of a single AOP measurement in "prolonged" second stage to predict a vaginal delivery (VD) was assessed. Fetal head descent, measured by AOP change/h (calculated from serial measurements), was compared between women who delivered vaginally and those who had a cesarean delivery (CD) for arrest of descent. Of the 191 women who met the inclusion criteria, 62 (32.5%) delivered spontaneously, 96 (50.2%) had a vacuum extraction (VE) and 33 (17.3%) had a CD. The mean AOP was wider among women who had VD (spontaneous or VE) compared to those who had CD (153° ± 19 vs. 133° ± 17, p < 0.001). Wider AOPs were associated with higher rates of VD and an AOP ≥ 127° was associated with a VD rate of 88.6% (148/167). Among the 87 women who had more than one AOP measurement, the mean AOP change per hour was higher in the VD group than in the CD group (15.1° ± 11.4° vs. 6.2° ± 6.3°, p < 0.001). Ultrasound-assessed fetal head station in nulliparous women with a protracted second stage of labor can be an accurate and objective additive tool in predicting the mode and interval time to delivery in real-life clinical practice.

Anatomical identification of ischial spines applicable to intrapartum transperineal ultrasound based on magnetic resonance imaging of pregnant women

Objective Intrapartum transperineal ultrasound is considered useful in judging fetal head descent; however, the inability to detect ischial spines on ultrasound images has been a drawback to its legitimacy. The current study aimed to determine the anatomical location of ischial spines, which can be directly applied to intrapartum transperineal ultrasound images. Method Based on magnetic resonance imaging (MRI) of 67 pregnant women at 33+2 [31+6-34+0] weeks gestation (median [interquartile range: IQR]), we calculated the angle between the pubic symphysis and the midpoint of ischial spines (midline symphysis-ischial spine angle; mSIA), which is theoretically equivalent to the angle of progression at fetal head station 0 on ITU, by determining spatial coordinates of pelvic landmarks and utilizing spatial vector analysis. Furthermore, we measured symphysis-ischial spine distance (SID), defined as the distance between the vertical plane passing the lower edge of the pubic symphysis and the plane that passes the ischial spines. Results As a result, mSIA was 109.6° [105.1–114.0] and SID 26.4 mm [19.8–30.7] (median, [IQR]). There was no correlation between mSIA or SID and maternal characteristics, including physique. Conclusions We established a novel method to measure the components of the pelvic anatomy by analyzing the three-dimensional coordinates of MRI data and identified the anatomical location of ischial spines which can be applied to ultrasound images. Our results provide valuable evidence to enhance the reliability of intrapartum transperineal ultrasound in assessing fetal head descent by considering the location of ischial spines.

Prediction of labor outcome by measuring the angle of progression using two dimensional trans-perineal Ultrasound: A prospective cohort study

Background: Failure of descent due to fetal malposition is one of the most common indications for performing surgical deliveries. It has recently been suggested that trans-perineal intra-partum ultrasonography may be useful in assessing fetal head engagement, position and station as well as it’s reliable, cheap, painless and effective tool. Measuring the ‘angle of progression’ could assist in the obstetrician’s decision regarding mode of delivery. Objectives: The primary outcome is to use the AOP to develop a predictive model for the probability of successful vaginal delivery. Secondary outcomes including assessment of possibly successful VBAC in previous one CS women. Methods: We recruited 500 women in labor. For each woman, a (TPU) was performed to measure the AOP in late first and second stages of labor. We compared AOP between women who delivered fetuses through vaginal route to those who delivered by CS. Results: Through 467 women included in the study, AOP was significantly Higher in spontaneous vaginal delivery group (with cut off 123°±8.5°) as compared with women delivered by vacuum or by CS (113°±10.5°) (P=0.003). The VBAC as another secodary outcome seems to be insignificant. Conclusions: TPU is safe, non-invasive and easily preformed technique which is useful to predict labor outcomes.

The Assessment of Intrapartum Transperineal Ultrasonographic Parameters for their Effectiveness in Evaluation of Progress of Labor and Prediction of Mode of Delivery in Egyptian Women

Introduction: High fetal head station has been associated with prolonged labor and delivery outcomes. Although clinical assessment of fetal head station is both subjective and unreliable, women with prolonged labor are subjected to multiple digital vaginal examinations. The use of ultrasound has been proposed to aid in the management of labor since 1990s. Ultrasound examination is more accurate and reproducible than clinical examination in the diagnosis of fetal head station and in the prediction of arrest of labor. Ultrasound examination can, to some extent, distinguish those women destined for spontaneous vaginal delivery and those destined for operative delivery and may predict the outcome of instrumental vaginal delivery. Such a technique has the potential to reduce the frequency of intrusive internal examinations and associated infection and could be useful in allowing the assessment of women in whom digital VE is traumatic or contra-indicated. Intrapartum ultrasound not only provides objective and quantitative data in labor, but also helps to make more reliable clinical decisions aiming to improve obstetric outcomes of both the mother and fetus as a supplementary tool for active management.&#x0D; Aim of the work: This study aims at assessing the value of intrapartum transperineal ultrasonography as a quantitative and objective tool in the evaluation of progress of labor and prediction of mode of delivery.&#x0D; Subjects: This study was a prospective observational study conducted on 600 primiparous women in active first stage of labor admitted to Kasr Al Ainy maternity hospital from January 2017 to June 2018. The studied population was divided into two groups. Group A of 300 women with normal progress of labor and group B of 300 women with prolonged 1st stage of labor.&#x0D; Methods: Fetal head station(FHS) was assessed clinically by digital vaginal examination (dVE) and sonographically by transperineal ultrasound measurement of head perineal distance (HPD) and angle of progression (AOP). Intrapartum care of the patient continued as normal based only on digital vaginal examinations using the modified WHO partogram. (1). Statistical analysis was targeted towards assessing the potential of the intrapartum ultrasonography in the evaluation of progress of labor and prediction of mode of delivery.&#x0D; Results: All studied parameters for assessment of FHS (dVE, HPD, and AOP) significantly corelated with each other and with both progress of labor and mode of delivery with P value (&lt;0.001). The highest sensitivity for prediction of progress of labor is observed using dVE (83%), the highest specificity is observed using AOP (78.3%). The highest sensitivity for prediction mode of delivery is for combined HPD &amp; AOP (97.7%) while the highest specificity is for AOP (81%). When combining both HPD and AOP for prediction of mode of delivery, the assessment of both parameters was found to have a high sensitivity of 97.7% and a high positive predictive value of 86.63%.&#x0D; Conclusion: Intrapartum ultrasound examination is a valuable tool in the prediction of progress of labor and mode of delivery. The assessment of fetal head station by transperineal ultrasound measurement of HPD and AOP is much more informative of the progress of labor and the mode of delivery than digital assessment of fetal head station.&#x0D; Keywords: Labor, intrapartum ultrasound, Angle of progression, Head perineal distance, fetal head station, digital vaginal examination.

Is duration of passive second stage associated with a risk of hysterotomy extension during cesarean?

ObjectiveTo assess obstetric factors associated with hysterotomy extension among women undergoing a second-stage cesarean.Study designThis 5-year retrospective cohort study (2013–2017) included all women with second-stage cesarean deliveries of live-born singleton fetuses in cephalic presentation at term. It took place at a tertiary center that practices delayed pushing. We performed univariable and multivariable logistic regression to assess the maternal, obstetric, and neonatal factors associated with hysterotomy extension mentioned in the surgical report. Operative time, postpartum hemorrhage, and maternal complications were also studied.ResultsOf the 3350 intrapartum cesareans, 2637 were performed at term for singleton fetuses in cephalic presentation: 747 (28.3%) during the second stage of labor, 83 (11.1%) of which were complicated by a hysterotomy extension. The median duration of the passive phase of the second stage did not differ between women with and without an extension (164 min versus 160 min, P = 0.85). No other second-stage obstetric characteristics, i.e., duration of the active phase, fetal head station, or fetal malposition, were associated with the risk of extension. Factors significantly associated with extension were the surgeon’s experience and forceps use during the cesarean. Women with an extension, compared to women without one, had a longer median operative time (49 min versus 32 min, P<0.001) and higher rates of postpartum hemorrhage and blood transfusion (respectively, 30.1% versus 15.1%, p = 0.002 and 7.2% versus 2.4%, P = 0.03).ConclusionThe risk of a hysterotomy extension does not appear to be associated with second-stage obstetric characteristics, including the duration of the passive phase of this stage. In our center, which practices delayed pushing, prolonging this passive phase beyond 2 hours does not increase the risk of hysterotomy extension in second-stage cesareans.