Head Station Research Articles

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.

Advanced midwifery practice: intrapartum ultrasonography to assess fetal head station and comparison with vaginal digital examination.

Vaginal digital examination is considered the gold standard to evaluate patients during labor and delivery. However, transperineal ultrasound has been suggested as an effective tool in determining fetal head station during labor. Angle of progression (AOP), head-perineal distance (HPD) and head-symphysis distance (HSD) are reliable parameters to assess fetal head station during labor. The study aims were to evaluate how midwives can use AOP, HSD, HPD to assess the accuracy of digital vaginal exploration limited to the fetal head station. Trained midwives for ultrasound analyses performed transperineal ultrasounds during the first stage of labor with 2D-convex probe in 62 pregnant women at term with a single fetus in cephalic presentation. Immediately before the intrapartum ultrasound, the birth attendant performed a digital examination to assess cervical dilatation and head station. The ultrasound scans were compared to the digital vaginal examination through the Tutschek's formula. AOP was wider in women who delivered vaginally without any complication if compared to "complicated delivery" group. HPD and HSD were greater in women who underwent an operative vaginal delivery or caesarean section. The vaginal exploration accuracy was 34%, but when ±1 cm was considered as tolerated, the overall accuracy was 74.19%. Midwives may include ultrasounds in their clinical practice after adequate training or under the supervision of an ultrasound professional as an adjunct tool during labor to evaluate its progress and prevent any deviation from physiology.

Ultrasound before operative vaginal delivery: why and how.

Safe management of the second stage of labor is important. Wait for spontaneous delivery, operative vaginal deliveries and second stage cesarean sections are all options when prolonged second stage occurs. The important question is which option to choose. Fetal head station and fetal head position are used to decide mode of delivery; this has traditionally been decided by performing a digital vaginal examination. Studies have shown that theses clinical examinations of both fetal head station and position are unreliable and that ultrasound might be better option. The International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) published in 2018 guidelines on intrapartum ultrasound and recommends that ultrasound is performed for ascertainment of fetal head position and station before considering or performing an instrumental vaginal delivery for slow progress or arrested labor in the second stage. The determination of the fetal head position, fetal head station and the movement of the fetal head can easily be determined with the help of ultrasound and can help the clinicians in making the right decision on how to proceed when prolonged second stage of labor is diagnosed.

449 Fetal head station at second stage dystocia- does it predict subsequent TOLAC success rate?

The factors associated with successful trial of labor after cesarean (TOLAC) among women with prior cesarean delivery (CD) for second-stage dystocia remain largely unestablished. We aimed to determine whether fetal head station at the index CD predicts the success rate of subsequent trial of labor among primiparous women. A retrospective cohort study conducted at two tertiary, university affiliated medical centers, including all primiparous women with subsequent delivery after CD for second-stage dystocia during 2009-2019. Overall, 481 primiparous women with prior CD for second-stage dystocia, had a subsequent delivery during study period. Of them, 171 (35.6%) women had an elective repeat CD and 310 (64.4%) attempted a TOLAC. Those undergoing TOLAC were younger (P<0.001), with lower rates of hypertensive disorders (P=0.005) and gestational diabetes (P=0.003) at the subsequent pregnancy. Of those undergoing TOLAC (n=310), 222 (71.6%) successfully delivered vaginally. The rate of successful TOLAC was significantly higher in those with fetal head station below the ischial spines at the index CD as compared to those with higher head station (79.0% vs. 60.5%, P<0.001). The proportion of infants weighing >3,500 grams in the subsequent delivery was lower in those with successful compared with failed TOLAC (29.7% vs. 43.2%, OR [95% CI]: 0.56 (0.33-0.93), P=0.03). In a multivariable analysis, lower fetal head station at the index CD was the only independent factor associated with TOLAC success (aOR [95% CI]: 2.38 (1.43, 3.96), P=0.001). Lower fetal head station at the index CD for second-stage dystocia was independently associated with higher VBAC rate, with an overall acceptable success rate. These findings should improve patient counseling and reassure those who wish to delivery vaginally after prior second-stage arrest.

480 Intrapartum sonographic features of cephalopelvic disproportion in non-occiput posterior fetuses: prospective multicenter study

To describe the intrapartum sonographic characteristics of cephalopelvic disproportion (CPD) in labor arrest in non-occiput posterior (OP) position. Prospective study conducted across three tertiary maternity Units and including women with prolonged first stage of labor and fetuses lying in non-OP position. In the recruited cases transabdominal ultrasound was performed in order to evaluate the degree of flection of the fetal head by means of the occiput-spine angle (OSA), while the sonographic indicators of head station – i.e. the angle-of-progression (AoP) and the head-perineum distance (HPD) – and additional signs of CPD were assessed at transperineal ultrasound. Obstetric intervention performed solely based on suspected fetal distress represented exclusion criteria for the study. Overall, 86 women were included. Spontaneous vaginal delivery, instrumental delivery and cesarean section were recorded in 45 (52.3%), 11 (12.8%) and 30 (34.9%) cases, respectively. A wider OSA (126.2+14.4 vs 114.5+23.6 degrees, p=0.006) and AoP (117.5+12.7 vs 104.0+10.7 degrees, p<0.001) and a shorter HPD (39.7+5.2 vs 49.0+9.4 mm, p<0.001) were measured in women who had vaginal delivery compared to those delivered by cesarean section. When investigating the correlation between the OSA and the sonographic indices of head station, the OSA showed a direct correlation with the AoP (Pearson’s correlation 0.449, p<0.01) but no correlation with the HPD (p=0.15); 9 cases showing a narrow AoP, a long HPD and a wide OSA and all delivered by cesarean section were labelled as outliers. Such cases showed a lower maternal height (p<0.01) and a higher ratio between the birthweight and the maternal height (p=0.04) compared to the non-outlier cases. Caput succedaneum and moulding were also noted at transperineal ultrasound in all the outlier cases. Findings from this study suggest that a discrepancy between the width of the OSA and the expected AoP and HPD represent sonographic indicators of CPD in non-OP fetuses diagnosed with labor arrest.

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.

Sonographic measurement of cervical length and head perineum distance before labor to predict time of delivery

Objectives This was an observational study on cervical length and head perineum distance and the prediction of time of delivery. One-hundred and twenty-five nulliparous women with uncomplicated, term, singleton pregnancy were recruited when they presented to the labor ward with show or infrequent painful uterine contractions (less than three contractions in ten minutes on a 30 min cardiotocogram). Apart from digital vaginal examination to assess cervical length and dilatation, sonographic cervical length and head perineum distance were measured by two-dimensional ultrasound. We compared women who delivered within 72 h of presentation of labor symptoms, with women who did not. After excluding ten women whose labor was induced and delivered within 72 h of presentation, one hundred and fifteen women were included for final data analysis. Main findings Forty-nine women (42.6%) delivered while sixty-six women (57.4%) remained undelivered at 72 h of presentation of symptoms of labor. There was no statistically significant difference between the two groups on age, presence of show, contractions, fetal head station and presentation and mode of delivery. For the group who had delivered within 72 h of presentation of labor symptoms, the mean sonographic cervical length was 1.87 cm ± 0.62 cm, while the head perineum distance was 6.01 cm ± 1.15 cm. For the other group, the mean sonographic cervical length was 2.10 cm ± 0.83 cm; head perineum distance was 6.03 cm ± 1.18 cm. There was no statistically significant difference between the groups for both sonographic cervical length (p = .90); and head perineum distance (p = .08). We also compared the cervical length measured by digital vaginal examination versus sonography. The median sonographic measurements were 1.47 cm, 2.11 cm and 2.79 cm at “1 cm,” “2 cm” and “3 cm” digital vaginal measurement, respectively. However, there was extensive overlap between digitally and sonographically measured cervical length. Prediction accuracy of cervical length and head perineum distance was poor. The area under curve (AUC) of receiver operating characteristic (ROC) curve were 0.433 for sonographic cervical length and 0.501 for HPD. Conclusion Transperineal sonographical assessment of cervical length and head perineum distance before labor was not useful in predicting the time of delivery. However, it can be explored as an alternative assessment method when digital vaginal examination is not preferred.

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

Fetal Head Station at Second-Stage Dystocia and Subsequent Trial of Labor After Cesarean Delivery Success Rate.

To investigate whether fetal head station at the index cesarean delivery is associated with a subsequent trial of labor success rate among primiparous women. A retrospective cohort study conducted at two tertiary medical centers included all primiparous women with subsequent delivery after cesarean delivery for second-stage dystocia during 2009-2019, identified from the electronic medical record databases. Univariate and multivariate analyses were performed to assess the factors associated with successful trial of labor after cesarean (TOLAC) (primary outcome). Additionally, all women with failed TOLAC were matched one-to-one to women with successful TOLAC, according to factors identified in the univariate analysis. Of 481 primiparous women with prior cesarean delivery for second-stage dystocia, 64.4% (n=310) attempted TOLAC, and 222 (71.6%) successfully delivered vaginally. The rate of successful TOLAC was significantly higher in those with fetal head station below the ischial spines at the index cesarean delivery, as compared with those with higher head station (79.0% vs 60.5%, odds ratio [OR] 2.46, 95% CI 1.49-4.08). The proportion of neonates weighing more than 3,500 g in the subsequent delivery was lower in those with successful TOLAC compared with failed TOLAC (29.7% vs 43.2%, OR 0.56, 95% CI 0.33-0.93). In a multivariable analysis, lower fetal head station at the index cesarean delivery was the only independent factor associated with TOLAC success (adjusted OR 2.38, 95% CI 1.43-3.96). Matching all women with failed TOLAC one-to-one to women with successful TOLAC, according to birth weight and second-stage duration at the subsequent delivery, lower fetal head station at the index cesarean delivery remained the only factor associated with successful TOLAC. Lower fetal head station at the index cesarean delivery for second-stage dystocia was independently associated with a higher vaginal birth after cesarean rate, with an overall acceptable success rate. These findings should improve patient counseling and reassure those who wish to deliver vaginally after prior second-stage arrest.

Determination of fetal head station: Do professors and residents of obstetrics and gynecology reach an agreement?

Background: Determination of fetal head station is an important factor during labor progress. This study evaluated the agreement and correlation between professors and residents of obstetrics and gynecology in the determination of fetal head station based on a vaginal examination during labor. Methods: In this cross-sectional study, term pregnant women with cephalic presentation in an active phase of labor underwent vaginal examinations simultaneously by residents and professors of obstetrics and gynecology. Their examination findings regarding a fetal head station, cervical dilation and effacement were recorded both by professors and the residents. Data were analyzed by SPSS version 16 using Spearman’s correlation and Intraclass Correlation Coefficient tests between results obtained by two groups of assessors (residents and professors). Results: Our data analysis showed that the agreement between obstetricians and residents for cervical dilatation, cervical effacement, and a fetal head station was 0.88, 0.9 and 0.67 respectively (p <0.001). The correlation between obstetricians and residents for determination of cervical dilatation, cervical effacement and, a fetal head station was 0.77, 0.79 and 0.52, respectively (p <0.001). Conclusions: The agreement and correlation between professors and residents in obstetrics and gynecology about the determination of fetal head station are lower than those for cervical dilatation and effacement. Because of the importance of accurate determination of fetal head station in the first stage of labor, a new approach (new invented device for determine fetal head station) should be developed to for determining of fetal station.

Transperineal ultrasound assessment of maternal pelvic floor at term and fetal head engagement.

To evaluate the association between pelvic floor dimensions in nulliparous women at term and fetal head engagement, as assessed by transperineal ultrasound. This was a prospective observational study of nulliparous women at term. Before the onset of labor, transperineal ultrasound was used to measure the anteroposterior diameter (APD) of the levator hiatus and the angle of progression (AoP) at rest, on maximum pelvic floor muscle contraction and on maximum Valsalva maneuver (before and after visual feedback). We assessed the correlation between pelvic floor static and dynamic dimensions (levator hiatal APD and levator ani muscle coactivation) and AoP, which is an objective index of fetal head engagement. In total, 282 women were included in the analysis. Among these, 211 (74.8%) women had a vaginal delivery while 71 (25.2%) had a Cesarean delivery. AoP was narrower in the Cesarean-delivery group at rest, on maximum pelvic floor muscle contraction and on maximum Valsalva, whereas no differences in levator hiatal APD were found between the two groups. We found a negative correlation between levator hiatal APD at rest, on maximum pelvic floor muscle contraction and on maximum Valsalva and the duration of the second stage of labor. There was a positive correlation between AoP and levator hiatal APD on maximum Valsalva maneuver after visual feedback (r = 0.15, P = 0.01). Women with levator ani muscle contraction on Valsalva maneuver (i.e. coactivation), both pre and post visual feedback, had a narrower AoP at rest and on maximum Valsalva. After visual feedback, women with levator ani muscle coactivation had a longer second stage of labor than did those without (80.8 ± 61.4 min vs 62.9 ± 43.4 min (P = 0.04)). Smaller pelvic floor dimensions and levator ani muscle coactivation are associated with higher fetal head station and with a longer second stage of labor in nulliparous women at term. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Intrapartum ultrasound at the initiation of the active second stage of labor predicts spontaneous vaginal delivery

Longer duration of active pushing during labor is associated with a higher rate of operative delivery and an increased risk of maternal and neonatal complications. Although immediate pushing at complete dilatation is associated with lower rates of chorioamnionitis and postpartum hemorrhage, it is also associated with a longer duration of pushing. This study aimed to evaluate whether fetal head station and position, as assessed by ultrasound at the beginning of the pushing process, can predict the mode of delivery and duration of pushing in nulliparous women. This prospective observational study included nulliparous women with neuraxial analgesia and complete cervical dilatation. The following sonographic parameters were assessed just before the beginning of the pushing process, at rest, and while pushing during contraction: head position, angle of progression, head-perineum distance, and head-symphysis distance. The change between rest and pushing was designated as delta angle of progression, delta head-perineum distance, and delta head-symphysis distance. The sonographic measurements and fetal head station assessed by vaginal examination were compared between women who had a spontaneous vaginal delivery to those who underwent an operative delivery, and between those who pushed for more or less than 1 hour. Of the 197 women included in this study, 166 (84.3%) had a spontaneous vaginal delivery, 31 (15.7%) had an operative delivery, 23 (11.6%) had a vacuum delivery, and 8 (4.0%) had a cesarean delivery. Spontaneous vaginal delivery and shorter duration of pushing (less than an hour) were significantly more common with a nonocciput posterior position (10.6% vs 47.3%; P<.005), a wider angle of progression, a shorter head-perineum distance and head-symphysis distance (both during rest and while pushing), and a lower fetal head station as assessed by digital vaginal examination. However, a logistic regression model revealed that only the angle of progression at rest and the delta angle of progression were independently associated with a spontaneous vaginal delivery with an area under the curve of 0.82 (95% confidence interval, 0.76-0.87; P<.0001) and 0.75 (95% confidence interval, 0.67-0.79; P<.0001), respectively. Ultrasound performed at the beginning of the active second stage of labor can assist in predicting the mode of delivery and duration of pushing and perform better than the traditional digital examination, with the angle of progression at rest and delta angle of progression being the best predictors.

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.

Operative Deliveries at Full Cervical Dilatation; 'Choosing Between Lesser of Two Evils': A Comparative Study of Morbidities of Vacuum Delivery and Caesarean Section

Introduction: Operative delivery at full cervical dilatation can be either a caesarean section or instrumental deliveries. Instrumental deliveries are well debated options for reducing caesarean section rates but they have their own set of maternal and fetal morbidities. CS at full dilatation of cervix is also demanding due to impacted fetal head. Choice between the two depends on the treating obstetrician. &#x0D; Objective: To assess perinatal morbidities between vacuum delivery and caesarean section at full cervical dilatation. &#x0D; Methodology: This is an observational cross-sectional comparative study done for the duration of one year from January to December 2019. Women undergoing vacuum delivery or caesarean section in full cervical dilatation were compared for maternal and neonatal morbidities. Risk factors associated with these morbidities were also assessed. The morbidities in each group were compared using Pearson's chi square test. Likelihood of morbidities in relation to risk factors was calculated using univariate logistic regression. &#x0D; Results: Prevalence of maternal complications in vacuum delivery was 33.3% (28) and in caesarean was 42.9% (15). Neonatal complications in vacuum delivery was 50% (42) and in caesarean was 48.6% (17). Being a referred case (OR=1.14) and a primigravida (OR=1.45) were risk factors for perinatal morbidities in vacuum delivery. Referred cases (OR=1.52), primigravidas (OR=5.90), head station lower than zero (OR=1.26) and birth weight of more than 3500 gms (OR=2.60) were associated with more number of morbidities in caesarean at full cervical dilatation.&#x0D; Conclusion Operative deliveries at full cervical dilatation, either vacuum or CS carry risk of maternal and neonatal morbidities. Obstetrician should make a decision keeping in mind certain risk factors like referred cases, parity, head station, number of pulls, method of delivery of head and fetal weight so that severe morbidities can be prevented.

Angle of progression in women undergoing trial of labor after cesarean section in predicting mode of delivery

Objective To assess the ability of ultrasonic measurement of angle of progression (AOP) in predicting mode of delivery in women undergoing vaginal birth after cesarean section (CS). Background The intrapartum ultrasound measurement of AOP is reliable regardless of the fetal head station assessed manually or the clinician's level of ultrasound experience. Patients and methods A prospective observational study was conducted from March 2019 to January 2020 at Menoufia University Hospital, including 100 patients with a history of previous one CS in spontaneous labor. Patients were followed up, and AOP was measured in them using transperineal ultrasound. Patients were divided into two groups according to mode of delivery as follows: group 1, delivered by CS, and group 2, delivered by normal vaginal delivery (NVD). Results The mean AOP was decreased in CS group (98.20 ± 15.83) than NVD group (112.21 ± 12.66). Additionally, at cutoff point of AOP less than 95 (86°), area under curve was 0.511 (95% confidence interval: 0.264–0.758; P = 0.024), with sensitivity of 71.4%, specificity of 85.5%, and accuracy 81.5%. However, at cutoff point of AOP more than 95 (113°), area under curve was 0.545 (95% confidence interval: 0.412–0.679; P = 0.016), with sensitivity of 85.7%, specificity of 69.4%, and accuracy 93.25%. Conclusions The AOP was significantly decreased in CS group than NVD group. The results prove a vital role for using this angle as a simple and accurate landmark to evaluate station of fetal head and provide a useful predictor for mode of delivery, particularly in patients with planned vaginal birth after cesarean delivery (VBAC).

The association between fetal head station at the first diagnosis of the second stage of labor and delivery outcomes

Controversy surrounds the impact of the fetal head station on labor duration and mode of delivery. Although an extensive body of evidence has been published evaluating fetal head station in early labor, there is a paucity of data on the impact of fetal head descent during the second stage. This study aimed to explore the association between fetal head station at the diagnosis of the second stage of labor and the second stage duration and the risk of operative delivery. This is a retrospective cohort study of all singleton vertex deliveries in a single tertiary center (2011-2016). Women were grouped according to fetal head station upon the diagnosis of the second stage of labor as follows: above (S<0), at the level (S=0), and below (S>0) the level of the ischial spine. The duration of the second stage and the risk of operative delivery were compared between the groups and stratified by parity. Overall, 34,334 women met the inclusion criteria. Of these, 18,743 (54.6%) were nulliparous and 15,591 (45.4%) were multiparous. Of the nulliparous women, 8.1%, 35.8%, and 56.1% were diagnosed as having fetal head above, at the level, and below the ischial spine upon second stage diagnosis. Of the multiparous women, 19.7%, 35.6%, and 44.7% were diagnosed as having fetal head above, at the level, and below the ischial spine. Fetal head station upon second stage diagnosis was independently and significantly associated with second stage duration (P<.001); however, its contribution was 4.5-fold among nulliparous women compared with multiparous women. In multivariable analysis, after controlling for maternal age, gestational age at delivery, prepregnancy body mass index, epidural anesthesia, and birthweight, the risk of operative delivery was substantially increased in a dose-dependent pattern for both nulliparous and multiparous women. The fetal head station at the first diagnosis of the second stage is significantly and independently associated with the duration of the second stage and correlated with the risk of operative delivery in both nulliparous and multiparous women (P<.001).

Association of traction force and adverse neonatal outcome in vacuum-assisted vaginal delivery: A prospective cohort study.

Traction force is a possible risk factor for adverse neonatal outcome in vacuum extraction delivery, but the knowledge is scarce and further investigation is needed. Our hypothesis was that high-level traction force increases the risk of admission to the neonatal intensive care unit. The study was a hospital-based prospective cohort study on low- and mid-vacuum extractions at the labor and delivery ward, Karolinska University Hospital, Huddinge, Sweden. Traction forces were measured in 331 women. An electronical handle was used to measure and register traction force. The main exposure variable was high-level traction force (≥75th percentile) during the first three pulls and the primary outcome was admission to the neonatal intensive care unit. Logistic regression was used to estimate the adjusted risk. Among the exposed, 14/84 (16.7%) were admitted to neonatal intensive care, and among the unexposed 10/247 (4%). The crude odds ratio (OR) of admission to the neonatal intensive care unit when exposed to high-level traction force was 4.7, and the adjusted (birthweight, gestational length, cup detachment, number of pulls, duration, duration >15minutes, mid-cavity fetal head station, failed extraction, indication and parity) OR was 2.85 (95% confidence interval [CI] 1.09-7.48). No significant effect was seen in Apgarscores <7 at 5minutes or pH<7.1. High-level traction force may be a risk factor for neonatal complications. Although these results do not mandate any alterations in clinical guidelines, perioperative feedback on traction force may be useful to alert the obstetrician to a timely conversion to cesarean section. To study plausible traction force specific outcomes such as head traumas, a larger sample size is required.

Sonopartogram versus conventional partogram for monitoring progress of labor: a prospective observational study

BackgroundRepeated digital vaginal examination during labor may be uncomfortable for women and increases the risk of ascending infection. Transperineal ultrasound can assess fetal head descent, position, and cervical dilatation without these side effects. This study was conducted to evaluate the accuracy of transperineal ultrasound in monitoring labor progress.ResultsThe study included 40 primigravida women in labor. Fair correlation was found between the assessment of fetal head station by vaginal examination (VE) and fetal head perineal distance (HPD) by transperineal ultrasound (TPUS) (Kendall’s tau-b (τ) = − 0.299, 95% CI = − 0.479 to − 0.0863, p value = .0063) (Spearman rho = − .3844, p value = .0143; r2 = 0.1478). Strong correlation was found between the cervical dilatation assessed by VE and by TPUS (Pearson’s r = .8601, 95% CI = 0.7493 to 0.9240, p value < .0001, r2 = 0.7396). There is moderate agreement between VE and TPUS as regards the assessment of head position on the face-clock [weighted kappa (κ) = .557, 95% CI = .362 to.753].ConclusionTransperineal ultrasound can be used as an alternative to repeated digital examination for assessment of labor progress.

Intrapartum ultrasound during rotational forceps delivery: a novel tool for safety, quality control, and teaching

Operative vaginal delivery and, in particular, rotational forceps delivery require extensive training, specific skills, and dexterity. Performed correctly, it can reduce the need for difficult late second-stage cesarean delivery and its associated complications. When rotation to occiput anterior position is achieved, pelvic trauma and anal sphincter injury commonly associated with direct delivery from occiput posterior positions may be avoided. We report the original and novel use of real-time intrapartum ultrasound simultaneously during Kielland's rotational forceps delivery to monitor correct execution and increase maternal safety. This is a prospective observational study performed at the Charité University Hospital in Berlin between 2013 and 2018. Simultaneous, real-time, intrapartum suprapubic ultrasound during Kielland's rotational forceps deliveries were performed in a series of laboring women with normal fetuses and arrest of labor in the late second stage and with a fetal head malposition, requiring operative vaginal delivery. In addition to vaginal palpation for head station, rotation, and asynclitism, intrapartum ultrasound was also used to objectively determine head station, head direction, and midline angle. The operator was not blinded to the ultrasound findings. The delivering obstetrician examined the woman and performed the delivery. An assistant, trained in intrapartum ultrasound, placed a curved-array transducer transversely in the midline just above the pubic bone to display the forceps blades being applied and the rotation of the fetal head in occiput anterior position. In all 32 laboring women included in the study, the blades were applied correctly and the fetal heads successfully rotated to an occiput anterior position with direct ultrasound confirmation, and vaginal delivery was achieved. There were no cases of difficult application, repeat application, slippage of the blades, or rotation of the fetal head in the wrong direction. Maternal outcomes showed no vaginal tears, cervical tears, or postpartum hemorrhage >500 mL. There was 1 case of third-degree perineal tear (3a). Neonatal outcomes included mild hyperbilirubinemia (n=1), small cephalohematoma conservatively managed (n=1), and early-onset group B streptococcus sepsis secondary to maternal colonization (n=1). There were no neonatal deaths. Ultrasound guidance during Kielland's rotational forceps delivery is an original and novel approach. We describe the use of intrapartum ultrasound in assessing fetal head station and position and also to simultaneously and objectively monitor performance of rotational forceps delivery. Intrapartum ultrasound enhances operator confidence and, possibly, patient safety. It is a valuable adjunct to obstetrical training and can improve learning efficiency. Real-time ultrasound guidance of fetal head rotation to occiput anterior position with Kielland's forceps may also protect the perineum and reduce anal sphincter injury. This novel approach can lead to a renaissance in the safe use of Kielland's forceps.

Feasibility, Reliability, and Agreement of Transperineal Ultrasound Measurement: Results from a Longitudinal Cohort Study

Objectives: To evaluate the feasibility, reliability, and agreement of serial transperineal ultrasound (TPU) assessment of fetal head station (parasagittal angle of progression [psAOP], head-perineum distance [HPD], and head-symphysis distance [HSD]) and sonographic cervical dilatation (SCD), compared to fetal head station and cervical dilatation determined by vaginal examination, respectively. Methods: This was a prospective longitudinal study in singleton pregnancies undergoing induction of labor at term. Paired assessment of fetal head station and cervical dilatation by vaginal examination, with TPU assessment of psAOP, HPD, HSD, and SCD was made serially. Feasibility, correlation, reliability, and agreement were determined. Results: 1,139 paired measurements among 326 women were included. psAOP and HPD were achievable in all assessments. HSD was not achievable in 3.4% (11/326) due to high fetal head station. Fetal head station by vaginal examination was positively correlated with psAOP (rho = 0.70) but negatively correlated with HPD (rho = −0.57) and HSD (rho = −0.52). The feasibility to measure SCD reduced as cervical dilatation increased. Cervical dilatation and SCD were positively correlated (rho = 0.96) with strong agreement (concordant correlation coefficient = 0.925). Conclusions: Measurements of psAOP and HPD are feasible and correlate significantly with fetal head station by vaginal examination. Measurement of HSD is not feasible when fetal head station is high. Measurement of SCD is feasible, but it is more difficult in the advanced stage of labor. The correlation, reliability, and agreement between SCD and cervical dilatation by vaginal examination are high.