Randomised Italian Sonography for occiput POSition Trial Ante vacuum (R.I.S.POS.T.A.)

A deep learning approach to identify the fetal head position using transperineal ultrasound during labor

OBJECTIVES

To develop a deep learning (DL)-model using convolutional neural networks (CNN) to automatically identify the fetal head position at transperineal ultrasound in the second stage of labor.

MATERIAL AND METHODS

Prospective, multicenter study including singleton, term, cephalic pregnancies in the second stage of labor. We assessed the fetal head position using transabdominal ultrasound and subsequently, obtained an image of the fetal head on the axial plane using transperineal ultrasound and labeled it according to the transabdominal ultrasound findings. The ultrasound images were randomly allocated into the three datasets containing a similar proportion of images of each subtype of fetal head position (occiput anterior, posterior, right and left transverse): the training dataset included 70 %, the validation dataset 15 %, and the testing dataset 15 % of the acquired images. The pre-trained ResNet18 model was employed as a foundational framework for feature extraction and classification. CNN1 was trained to differentiate between occiput anterior (OA) and non-OA positions, CNN2 classified fetal head malpositions into occiput posterior (OP) or occiput transverse (OT) position, and CNN3 classified the remaining images as right or left OT. The DL-model was constructed using three convolutional neural networks (CNN) working simultaneously for the classification of fetal head positions. The performance of the algorithm was evaluated in terms of accuracy, sensitivity, specificity, F1-score and Cohen's kappa.

RESULTS

Between February 2018 and May 2023, 2154 transperineal images were included from eligible participants across 16 collaborating centers. The overall performance of the model for the classification of the fetal head position in the axial plane at transperineal ultrasound was excellent, with an of 94.5 % (95 % CI 92.0--97.0), a sensitivity of 95.6 % (95 % CI 96.8-100.0), a specificity of 91.2 % (95 % CI 87.3-95.1), a F1-score of 0.92 and a Cohen's kappa of 0.90. The best performance was achieved by the CNN1 - OA position vs fetal head malpositions - with an accuracy of 98.3 % (95 % CI 96.9-99.7), followed by CNN2 - OP vs OT positions - with an accuracy of 93.9 % (95 % CI 89.6-98.2), and finally, CNN3 - right vs left OT position - with an accuracy of 91.3 % (95 % CI 83.5-99.1).

CONCLUSIONS

We have developed a DL-model capable of assessing fetal head position using transperineal ultrasound during the second stage of labor with an excellent overall accuracy. Future studies should validate our DL model using larger datasets and real-time patients before introducing it into routine clinical practice.

The use of intrapartum ultrasound in operative vaginal birth: a retrospective cohort study

BACKGROUND

Poor outcomes from operative vaginal birth have been associated with failure to recognize malposition, breakdown in interdisciplinary communication, and deviation from accepted guidelines. We recently implemented a safety bundle including routine intrapartum ultrasound and a structured time-out and procedural checklist aiming to reduce maternal and perinatal morbidity from operative vaginal birth.

OBJECTIVE

This study aimed to compare births where intrapartum ultrasound was used and those where it was not used during a safety bundle implementation period at Monash Health.

STUDY DESIGN

We performed a retrospective cohort study at Monash Health during the transitional phase of implementing an operative vaginal birth safety bundle. We studied all women with operative vaginal birth and fully dilated cesarean delivery with a singleton cephalic term fetus. We compared births for which intrapartum ultrasound was used and those for which it was not. The primary outcome was neonates delivered in an unexpected position. Neonatal and maternal morbidity were also assessed, including a neonatal composite of Apgar score <7 at 5 minutes, cord lactate >8 mmol/L, need for resuscitation, significant birth trauma, or neonatal intensive care unit admission. To control for confounding by indication, we estimated propensity scores for the probability of using intrapartum ultrasound for each case based on maternal and labor characteristics, and adjusted the effect estimates for the propensity scores using multivariable logistic regression models.

RESULTS

From August 2022 to July 2023, there were 1205 operative vaginal births or fully dilated cesarean deliveries at Monash Health, including 743 (61.7%) forceps, 346 (28.7%) vacuum, and 116 (9.6%) fully dilated cesarean deliveries. Over this time, we observed increased uptake of intrapartum ultrasound from 26% in August 2022 to 60% (P<.001) in July 2023, of the time-out from 21% to 58% (P<.001), and the checklist from 33% to 80% (P<.001) of operative second-stage births. Among the births where intrapartum ultrasound was used (n=509), compared with those where it was not (n=696), there were significantly more forceps births (67% vs 58%; adjusted odds ratio, 1.35; 95% confidence interval, 1.05-1.74; P=.021) and a reduction in vacuum births (24% vs 32%; adjusted odds ratio, 0.77; 95% confidence interval, 0.58-1.01; P=.059). There were no significant differences in fully dilated cesarean delivery or maternal morbidity. Intrapartum ultrasound use was associated with significantly fewer infants being delivered in an unexpected position (0.2% vs 2.2%; adjusted odds ratio, 0.08; 95% confidence interval, 0.00-0.44; P=.019) and a significant reduction in composite neonatal morbidity (22% vs 25%; adjusted odds ratio, 0.73; 95% confidence interval, 0.54-0.97; P=.031).

CONCLUSION

During the implementation of a safety bundle, the use of ultrasound before operative vaginal birth was associated with fewer infants delivered in an unexpected position and reduced neonatal morbidity.

Sonographic evaluation of the fetal head position and attitude during labor

Fetal malpresentation, malposition, and asynclitism are among the most common determinants of a protracted active phase of labor, arrest of dilatation during the first stage, and arrest of descent in the second stage. The diagnosis of these conditions is traditionally based on vaginal examination, which is subjective and poorly reproducible. Intrapartum sonography has been demonstrated to yield higher accuracy than vaginal examination in characterizing fetal malposition, and some guidelines endorse its use for the verification of the occiput position before performing an instrumental delivery. It is also useful for the objective diagnosis of the malpresentation or asynclitism of the fetal head. According to our experience, the sonographic assessment of the head position in labor is simple to perform also for clinicians with basic ultrasound skills, whereas the assessment of malpresentation and asynclitism warrants a higher level of expertise. When clinically appropriate, the fetal occiput position can be easily ascertained using transabdominal sonography combining the axial and the sagittal planes. With the transducer positioned on the maternal suprapubic region, the fetal head can be visualized, and landmarks including the fetal orbits, the midline, and the occiput itself with the cerebellum and the cervical spine (depending on the type of fetal position) can be demonstrated below the probe. Sinciput, brow, and face represent the 3 "classical" variants of cephalic malpresentation and are characterized by a progressively increasing degree of deflexion from vertex presentation. Transabdominal sonography has been recently suggested for the objective assessment of the fetal head attitude when a cephalic malpresentation is clinically suspected. Fetal attitude can be evaluated on the sagittal plane with either a subjective or an objective approach. Two different sonographic parameters such as the occiput-spine angle and the chin-chest angle have been recently described to quantify the degree of flexion in fetuses in non-occiput-posterior or occiput-posterior position, respectively. Finally, although clinical examination still represents the mainstay of diagnosis of asynclitism, the use of intrapartum sonography has been shown to confirm the digital findings. The sonographic diagnosis of asynclitism can be achieved in expert hands using a combination of transabdominal and transperineal sonography. At suprapubic sonography on the axial plane only, 1 orbit can be visualized (squint sign) while the sagittal suture appears anteriorly (posterior asynclitism) or posteriorly (anterior asynclitism) displaced. Eventually the transperineal approach does not allow the visualization of the cerebral midline on the axial plane if the probe is perpendicular to the fourchette. In this expert review we summarize the indications, technique, and clinical role of intrapartum sonographic evaluation of fetal head position and attitude.

Descent of the presenting part assessed with ultrasound

Fetal head descent can be expressed as fetal station and engagement. Station is traditionally based on clinical vaginal examination of the distal part of the fetal skull and related to the level of the ischial spines. Engagement is based on a transabdominal examination of the proximal part of the fetal head above the pelvic inlet. Clinical examinations are subjective, and objective measurements of descent are warranted. Ultrasound is a feasible diagnostic tool in labor, and fetal lie, station, position, presentation, and attitude can be examined. This review presents an overview of fetal descent examined with ultrasound. Ultrasound was first introduced for examining fetal descent in 1977. The distance from the sacral tip to the fetal skull was measured with A-mode ultrasound, but more convenient transperineal methods have since been published. Of those, progression distance, angle of progression, and head-symphysis distance are examined in the sagittal plane, using the inferior part of the symphysis pubis as reference point. Head-perineum distance is measured in the frontal plane (transverse transperineal scan) as the shortest distance from perineum to the fetal skull, representing the remaining part of the birth canal for the fetus to pass. At high stations, the fetal head is directed downward, followed with a horizontal and then an upward direction when the fetus descends in the birth canal and deflexes the head. Head descent may be assessed transabdominally with ultrasound and measured as the suprapubic descent angle. Many observational studies have shown that fetal descent assessed with ultrasound can predict labor outcome before induction of labor, as an admission test, and during the first and second stage of labor. Labor progress can also be examined longitudinally. The International Society of Ultrasound in Obstetrics and Gynecology recommends using ultrasound in women with prolonged or arrested first or second stage of labor, when malpositions or malpresentations are suspected, and before an operative vaginal delivery. One single ultrasound parameter cannot tell for sure whether an instrumental delivery is going to be successful. Information about station and position is a prerequisite, but head direction, presentation, and attitude also should be considered.

Impact of additional theoretical training program in the diagnosis of the fetal head position during labor: a prospective observational study

BACKGROUND

The accuracy of transvaginal digital examination in determining foetal head position is not high enough. This study aimed to evaluate whether an additional training on our new theory could improve the diagnostic accuracy of the foetal head position.

METHODS

This was a prospective study conducted at a 3a grade hospital. The study included 2 residents in their first year of training in obstetrics without prior experience in transvaginal digital examination. In the observational study, 600 pregnant women without contraindications to vaginal delivery were included. Two residents were simultaneously trained in the theory of traditional vaginal examination, but resident B received an additional theoretical training program. The pregnant women were randomly assigned to have the foetal head position examined by resident A and resident B. The foetal head position was then confirmed by ultrasound, which was performed by the main investigator. After 300 examinations were independently performed by each resident, the accuracy of foetal head position and perinatal outcomes were compared between the two groups.

RESULTS

During the 3-month period, 300 post training transvaginal digital examinations were performed by each resident in our hospital. The two groups were found to be homogeneous for age at delivery, BMI before delivery, parity, gestational weeks at delivery, the rate of epidural analgesia, foetal head position, presence of caput succedaneum, presence of moulding and foetal head station(p > 0.05). The diagnostic accuracy of head position by digital examination was higher for resident B, who was subjected to an additional theoretical training program, than for resident A (75.00% vs. 60.67%, p < 0.001). There were no significant differences in maternal and neonatal outcomes between the two groups (p > 0.05).

CONCLUSION

An additional theoretical training program for residents increased the accuracy of vaginal assessment of foetal head position.

TRIAL REGISTRATION

Registered at Chinese Clinical Trial Registry Platform (ChiCTR2200064783), October 17, 2022. https://www.chictr.org.cn/edit.aspx?pid=182857&htm=4.

Assessment of labor progress by ultrasound vs manual examination: a randomized controlled trial

BACKGROUND

Assessment of labor progress via digital examination is considered the standard of care in most delivery rooms. However, this method can be stressful, painful, and imprecise, and multiple examinations increase the risk for chorioamnionitis. Intrapartum ultrasound was found to be an objective, noninvasive tool to monitor labor progression.

OBJECTIVE

This study aimed to investigate whether, among nulliparous women, the use of intrapartum ultrasound can reduce the rate of intrapartum fever by reducing the number of digital examinations.

STUDY DESIGN

This was a prospective, randomized controlled trial in term nulliparas admitted with prelabor rupture of membranes, induction of labor, or in latent phase of labor with a cervical dilation of <4 cm. Women were randomized into 1 of the following 2 arms: (1) labor progress assessed by ultrasound, avoiding digital examinations as much as possible; and (2) control group in which labor progression was assessed according to the regular protocol. Before the study, all labor ward physicians underwent training in intrapartum ultrasound.

RESULTS

A total of 90 women were randomized to the ultrasound group and 92 were randomized to the control group. When compared with the control group, the ultrasound group had significantly lower rates of intrapartum fever (11.1% vs 26.1%; P=.01), clinical chorioamnionitis (3.3% vs 16.5%; P>.01), and histologic chorioamnionitis (2.2% vs 9.8%; P=.03). The median number of digital examinations was significantly lower in the ultrasound group (5; interquartile range, 4-6) than in the control group (8; interquartile range, 6-10; P<.01). The median number of digital examinations per hour in the ultrasound group was significantly lower than in the control group (0.2 vs 0.4; P<.01). The induction rates, time from admission to delivery, mode of delivery, Apgar score at 5 minutes, and neonatal intensive care unit admission rates did not differ significantly between the groups.

CONCLUSION

The use of intrapartum ultrasound lessens the total number of digital examinations needed to be performed during labor and, consequently, the incidence of intrapartum fever and chorioamnionitis are reduced. No adverse effects on labor progression and short-term maternal or neonatal outcomes were noted.

Sonographic knowledge of occiput position to decrease failed operative vaginal delivery: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

This study aimed to assess the efficacy of sonographic assessment of fetal occiput position before operative vaginal delivery to decrease the number of failed operative vaginal deliveries.

DATA SOURCES

The search was conducted in MEDLINE, Embase, Web of Science, Scopus, ClinicalTrial.gov, Ovid, and Cochrane Library as electronic databases from the inception of each database to April 2021. No restrictions for language or geographic location were applied.

STUDY ELIGIBILITY CRITERIA

Selection criteria included randomized controlled trails of pregnant women randomized to either sonographic or clinical digital diagnosis of fetal occiput position during the second stage of labor before operative vaginal delivery.

METHODS

The primary outcome was failed operative vaginal delivery, defined as a failed fetal operative vaginal delivery (vacuum or forceps) extraction requiring a cesarean delivery or forceps after failed vacuum. The summary measures were reported as relative risks or as mean differences with 95% confidence intervals using the random effects model of DerSimonian and Laird. An I² (Higgins I²) >0% was used to identify heterogeneity.

RESULTS

A total of 4 randomized controlled trials including 1007 women with singleton, term, cephalic fetuses randomized to either the sonographic (n=484) or clinical digital (n=523) diagnosis of occiput position during the second stage of labor before operative vaginal delivery were included. Before operative vaginal delivery, fetal occiput position was diagnosed as anterior in 63.5% of the sonographic diagnosis group vs 69.5% in the clinical digital diagnosis group (P=.04). There was no significant difference in the rate of failed operative vaginal deliveries between the sonographic and clinical diagnosis of occiput position groups (9.9% vs 8.2%; relative risk, 1.14; 95% confidence interval, 0.77-1.68). Women randomized to sonographic diagnosis of occiput position had a significantly lower rate of occiput position discordance between the evaluation before operative vaginal delivery and the at birth evaluation when compared with those randomized to the clinical diagnosis group (2.3% vs 17.7%; relative risk, 0.16; 95% confidence interval, 0.04-0.74; P=.02). There were no significant differences in any of the other secondary obstetrical and perinatal outcomes assessed.

CONCLUSION

Sonographic knowledge of occiput position before operative vaginal delivery does not seem to have an effect on the incidence of failed operative vaginal deliveries despite better sonographic accuracy in the occiput position diagnosis when compared with clinical assessment. Future studies should evaluate how a more accurate sonographic diagnosis of occiput position or other parameters can lead to a safer and more effective operative vaginal delivery technique.

Novel artificial intelligence approach for automatic differentiation of fetal occiput anterior and non-occiput anterior positions during labor

OBJECTIVES

To describe a newly developed machine-learning (ML) algorithm for the automatic recognition of fetal head position using transperineal ultrasound (TPU) during the second stage of labor and to describe its performance in differentiating between occiput anterior (OA) and non-OA positions.

METHODS

This was a prospective cohort study including singleton term (> 37 weeks of gestation) pregnancies in the second stage of labor, with a non-anomalous fetus in cephalic presentation. Transabdominal ultrasound was performed to determine whether the fetal head position was OA or non-OA. For each case, one sonographic image of the fetal head was then acquired in an axial plane using TPU and saved for later offline analysis. Using the transabdominal sonographic diagnosis as the gold standard, a ML algorithm based on a pattern-recognition feed-forward neural network was trained on the TPU images to discriminate between OA and non-OA positions. In the training phase, the model tuned its parameters to approximate the training data (i.e. the training dataset) such that it would identify correctly the fetal head position, by exploiting geometric, morphological and intensity-based features of the images. In the testing phase, the algorithm was blinded to the occiput position as determined by transabdominal ultrasound. Using the test dataset, the ability of the ML algorithm to differentiate OA from non-OA fetal positions was assessed in terms of diagnostic accuracy. The F₁ -score and precision-recall area under the curve (PR-AUC) were calculated to assess the algorithm's performance. Cohen's kappa (κ) was calculated to evaluate the agreement between the algorithm and the gold standard.

RESULTS

Over a period of 24 months (February 2018 to January 2020), at 15 maternity hospitals affiliated to the International Study group on Labor ANd Delivery Sonography (ISLANDS), we enrolled into the study 1219 women in the second stage of labor. On the basis of transabdominal ultrasound, they were classified as OA (n = 801 (65.7%)) or non-OA (n = 418 (34.3%)). From the entire cohort (OA and non-OA), approximately 70% (n = 824) of the patients were assigned randomly to the training dataset and the rest (n = 395) were used as the test dataset. The ML-based algorithm correctly classified the fetal occiput position in 90.4% (357/395) of the test dataset, including 224/246 with OA (91.1%) and 133/149 with non-OA (89.3%) fetal head position. Evaluation of the algorithm's performance gave an F₁ -score of 88.7% and a PR-AUC of 85.4%. The algorithm showed a balanced performance in the recognition of both OA and non-OA positions. The robustness of the algorithm was confirmed by high agreement with the gold standard (κ = 0.81; P < 0.0001).

CONCLUSIONS

This newly developed ML-based algorithm for the automatic assessment of fetal head position using TPU can differentiate accurately, in most cases, between OA and non-OA positions in the second stage of labor. This algorithm has the potential to support not only obstetricians but also midwives and accoucheurs in the clinical use of TPU to determine fetal occiput position in the labor ward. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Ultrasound vs routine care before instrumental vaginal delivery: A systematic review and meta-analysis

INTRODUCTION

The objective was to report the role of intrapartum ultrasound examination in affecting maternal and perinatal outcome in women undergoing instrumental vaginal delivery.

MATERIAL AND METHODS

MEDLINE, Embase, CINAHL, Google Scholar and ClinicalTrial.gov databases were searched. Inclusion criteria were randomized controlled trials comparing ultrasound assessment of fetal head position vs routine standard care (digital examination) before instrumental vaginal delivery (either vacuum or forceps). The primary outcome was failed instrumental delivery extraction followed by cesarean section. Secondary outcomes were postpartum hemorrhage, 3rd or 4th degree perineal lacerations, episiotomy, prolonged hospital stay, Apgar score<7 at 5 min, umbilical artery pH <7.0 and base excess greater than -12 mEq, admission to neonatal intensive care unit (NICU), shoulder dystocia, birth trauma, a composite score of adverse maternal and neonatal outcome and incorrect diagnosis of fetal head position. Risk of bias was assessed using the Revised Cochrane risk-of-bias tool for randomized trials (RoB-2). The quality of evidence and strength of recommendations were assessed using the Grading of Recommendations Assessment Development and Evaluation (GRADE) methodology. Head-to-head meta-analyses using a random-effect model were used to analyze the data and results are reported as relative risk with their 95% confidence intervals.

RESULTS

Five studies were included (1463 women). There was no difference in the maternal, pregnancy or labor characteristics between the two groups. An ultrasound assessment prior to instrumental vaginal delivery did not affect the cesarean section rate compared with standard care (p = 0.805). Likewise, the risk of composite adverse maternal outcome (p = 0.428), perineal lacerations (p = 0.800), postpartum hemorrhage (p = 0.303), shoulder dystocia (p = 0.862) and prolonged stay in hospital (p = 0.059) were not different between the two groups. Composite adverse neonatal outcome was not different between the women undergoing and those not undergoing ultrasound assessment prior to instrumental delivery (p = 0.400). Likewise, there was no increased risk with abnormal Apgar score (p = 0.882), umbilical artery pH < 7.2 (p = 0.713), base excess greater than -12 (p = 0.742), admission to NICU (p = 0.879) or birth trauma (p = 0.968). The risk of having an incorrect diagnosis of fetal head position was lower when ultrasound was performed before instrumental delivery, with a relative risk of 0.16 (95% confidence interval 0.1-0.3; I² :77%, p < 0.001).

CONCLUSIONS

Although ultrasound examination was associated with a lower rate of incorrect diagnoses of fetal head position and station, this did not translate to any improvement of maternal or neonatal outcomes.

Number and quality of randomized controlled trials in obstetrics published in the top general medical and obstetrics and gynecology journals

BACKGROUND

There has been an increasing number of randomized controlled trials published in obstetrics and maternal-fetal medicine to reduce biases of treatment effect and to provide insights on the cause-effect of the relationship between treatment and outcomes.

OBJECTIVE

This study aimed to identify obstetrical randomized controlled trials published in top weekly general medical journals and monthly obstetrics and gynecology journals, to assess their quality in reporting and identify factors associated with publication in different journals.

STUDY DESIGN

The 4 weekly medical journals with the highest 2019 impact factor (New England Journal of Medicine, The Lancet, The Journal of the American Medical Association, and British Medical Journal), the top 4 monthly obstetrics and gynecology journals with obstetrics-related research (American Journal of Obstetrics & Gynecology, Ultrasound in Obstetrics & Gynecology, Obstetrics & Gynecology, and the British Journal of Obstetrics and Gynaecology), and the American Journal of Obstetrics & Gynecology Maternal-Fetal Medicine were searched for obstetrical randomized controlled trials in the years 2018 to 2020. The primary outcome was the number of obstetrical randomized controlled trials published in the obstetrics and gynecology journals vs the weekly medical journals and the percentage of trials published, overall and per journal. The secondary outcomes included the proportion of positive vs negative trials overall and per journal and the assessment of the study characteristics of published trials, including quality assessment criteria.

RESULTS

Of the 4024 original research articles published in the 9 journals during the 3-year study period, 1221 (30.3%) were randomized controlled trials, with 137 (11.2%) randomized controlled trials being in obstetrics (46 in 2018, 47 in 2019, and 44 studies in 2020). Furthermore, 33 (24.1%) were published in weekly medical journals, and 104 (75.9%) were published in obstetrics and gynecology journals. The percentage of obstetrical randomized controlled trials published ranged from 1.5% to 9.6% per journal. Overall, 34.3% of obstetrical trials were statistically significant or "positive" for the primary outcome. Notably, 24.8% of the trials were retrospectively registered after the enrollment of the first study patient. Trials published in the 4 weekly medical journals enrolled significantly more patients (1801 vs 180; P<.001), received more often funding from the federal government (78.8% vs 35.6%; P<.001), and were more likely to be multicenter (90.9% vs 42.3%; P<.001), non-United States based (69.7% vs 49.0%; P=.03), and double blinded (45.5% vs 18.3%; P=.003) than trials published in the obstetrics and gynecology journals. There was no difference in study type (noninferiority vs superiority) and trial quality characteristics, including pretrial registration, ethics approval statement, informed consent statement, and adherence to the Consolidated Standards of Reporting Trials guidelines statement between studies published in weekly medical journals and studies published in obstetrics and gynecology journals.

CONCLUSION

Approximately 45 trials in obstetrics are being published every year in the highest impact journals, with one-fourth being in the weekly medical journals and the remainder in the obstetrics and gynecology journals. Only about a third of published obstetrical trials are positive. Trials published in weekly medical journals are larger, more likely to be funded by the government, multicenter, international, and double blinded. Quality metrics are similar between weekly medical journals and obstetrics and gynecology journals.

Women's compliance with ultrasound in labor: a prospective observational study

OBJECTIVE

To explore women's compliance with ultrasound evaluation (UE) during labor compared with standard vaginal examination (VE).

METHODS

This is a prospective observational cohort study including uncomplicated singleton pregnancies with the fetus in vertex presentation from 37 weeks of gestation. Labor progress was assessed by both VE and UE. Women acceptability was assessed using a modified Wijma Delivery experience questionnaire (W-DEQ) based on six different items and resulting in a score ranging from 6 (not tolerated) to 36 (well tolerated). The primary outcome of the study was to compute the differences in the overall modified W-DEQ questionnaire between UE and VE. Secondary outcomes were to assess the differences between UE and VE in each individual item of modified W-DEQ questionnaire and to elucidate whether such differences persist in pregnancies experiencing compared to those not experiencing prolonged labor or unplanned emergency operative delivery.

RESULTS

One hundred and twenty-four women were included in the study and 109 completed the full questionnaire. The overall global acceptability score was significantly higher for UE compared to VE (27 IQR 25-29 versus 18 IQR 16-22; p ≤ .001). When stratifying the analysis to each individual item of the W-DEQ questionnaire separately, significant differences for intrusiveness (p = .04); painful (p = .01) and privacy ensured (p = .01) were found between UE and VE. In pregnancies experiencing prolonged labor, the global W-DEQ acceptability score for UE resulted significantly higher (30 versus 23; p = .005) than in those delivering within 12 hours. Likewise, UE acceptability score was significantly higher (28 IQR 24-30 versus 22 IQR 20-25; p = .01) in women having spontaneous vaginal birth compared to those undergoing operative delivery. Finally, there was no difference in the acceptability score between women with spontaneous onset of labor compared to those undergoing elective induction.

CONCLUSIONS

UE is better tolerated VE for assessment of labor progress; women's compliance with UE prior to delivery increased in the presence of prolonged labor or unplanned operative delivery.

Giant splenic cyst with expectant management in pregnancy: A case report and review of the literature

A 22-year-old primigravida was diagnosed with an 18-cm splenic cyst during routine third-trimester routine ultrasound examination. She was referred to a tertiary obstetric hospital and after multidisciplinary consultation, expectant management was decided on. Induction of labour was performed at term and she delivered vaginally with vacuum extractor application without complications. Percutaneous aspiration and sclerotherapy of the cyst was performed one week after delivery. She was hemodynamically stable throughout.

•

The diagnosis of large splenic cyst during pregnancy is a rare event and management is not standardized.

•

Different managements have been reported, but no strong evidence was found to support the superiority of any single treatment.

•

We report a case of a hemodynamically stable woman diagnosed with a large splenic cyst in the third trimester.

•

Expectant management was decided on, induction of labour was performed at term and the patient delivered vaginally.

•

Pregnant women diagnosed with a splenic cyst should be managed by a multidisciplinary team.

Transabdominal and transperineal ultrasound vs routine care before instrumental vaginal delivery - A randomized controlled trial

INTRODUCTION

The role of intrapartum ultrasound as an ancillary method to instrumental vaginal delivery is yet to be determined. This study aimed to compare the use of transabdominal and transperineal ultrasound with routine clinical care before performing an instrumental vaginal delivery, regarding the incidence of adverse maternal and neonatal outcomes.

MATERIAL AND METHODS

A randomized controlled trial was conducted between October 2016 and March 2019 in two tertiary care maternity hospitals in Lisbon, Portugal. Women at term, with full cervical dilatation, singleton fetuses in cephalic presentation, and with an established indication for instrumental vaginal delivery, were approached for enrollment. After informed consent was obtained, randomization into one of two groups was carried out. In the experimental arm, women underwent transabdominal ultrasound for determination of the fetal head position and transperineal ultrasound for evaluation of the angle of progression, before instrumental vaginal delivery. In the control arm, no ultrasound was carried out before instrumental vaginal delivery. Primary outcomes were composite measures of maternal and neonatal morbidity. Composite maternal morbidity consisted of severe postpartum hemorrhage, perineal trauma, and prolonged hospital stay. Composite neonatal morbidity consisted of low 5-minute Apgar score, umbilical artery metabolic acidosis, birth trauma, and neonatal intensive care unit admission.

RESULTS

A total of 222 women were enrolled (113 in the experimental arm and 109 in the control arm). No significant differences between the two arms were found in composite measures of maternal (23.9% in the experimental group vs 22.9% in the control group, odds ratio 1.055, 95% CI 0.567-1.964) or neonatal morbidity (9.7% in the experimental group vs 6.4% in the control group, odds ratio 1.571, 95% CI 0.586-4.215), nor in any of the individual outcomes.

CONCLUSIONS

In this small randomized controlled trial that was stopped for futility before reaching the required sample size, transabdominal and transperineal ultrasound performed just before instrumental vaginal delivery did not reduce the incidence of adverse maternal and neonatal outcomes, when compared with routine clinical care.

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.

Impact of ultrasound guided training in the diagnosis of the fetal head position during labor: A prospective observational study

OBJECTIVES

To assess whether the additional training with transabdominal ultrasound may improve the accuracy of the transvaginal digital examination in the assessment of the fetal head position during the active stage of labor.

METHODS

Prospective observational study involving 2 residents in their 1 st year of training in Obstetrics with no prior experience in neither transvaginal digital examination nor ultrasound. Women with term, cephalic presenting fetus and active labor with cervical dilation ≥ 8 cm and ruptured membranes were included. In the preliminary phase of the study, the resident A ("blinded") was assigned to assess the fetal head position by transvaginal digital examination, while the resident B ("unmasked") performed transvaginal digital examination following transabdominal ultrasound, which was considered to be the gold standard to determine the fetal head position. After 50 examinations independently performed by each resident in the training phase, a post-training phase of the study was carried out to compare the accuracy of each resident in the diagnosis of fetal head position by digital assessment. The occiput position was eventually confirmed by ultrasound performed by the main investigator.

RESULTS

Over a 6 months period, 90 post-training vaginal examinations were performed by each resident. The number of incorrect diagnoses of head position was higher for the "blinded" resident compared with the "unmasked" resident subjected to the ultrasound training (28/90 or 31.1 % vs 15/90 or 16.7 % p = 0.02). For both residents a wrong diagnosis was more likely with non-OA vs OA fetuses but this difference was statistically significant for the "blinded" Resident (10/20 or 50 % vs 18/70 or 25.7 % p = 0.039) but not for the "unmasked" Resident (5/18 or 27.9 % vs 10/72 or 13.9 % p = 0.16).

CONCLUSION

The addition of transabdominal ultrasound as a training tool in the determination of the fetal head position during labor seems to improve the accuracy of the transvaginal digital examination in unexperienced residents.

Ultrasound feedback training increases trainee accuracy in vaginal assessment of fetal head position in labor

OBJECTIVE

To evaluate the impact of an immediate ultrasound feedback intervention on trainee accuracy in vaginal-examination-based assessment of fetal head position.

METHODS

This was a prospective cohort study conducted at a single tertiary care center. Six third-year and six fourth-year residents in an obstetrics and gynecology residency training program were the study subjects. The third-year residents underwent a training intervention in which they assessed fetal head position by transvaginal digital examination and then received immediate feedback through ultrasound demonstration of the actual position. All examinations were performed in women with a singleton gestation ≥ 35 weeks and cervical dilation ≥ 8 cm, following rupture of membranes. The comparison groups were third-year residents before, during and after training and fourth-year residents who were not exposed to the training intervention. The primary outcome was the difference in accuracy of fetal-head-position assessment on vaginal examination by third-year residents before and after ultrasound feedback training. Univariate and multivariate analyses were performed to identify factors associated with digital examination accuracy.

RESULTS

Overall, 390 examinations were performed. The accuracy of fetal-head-position assessments of third-year residents was 55% (53/96) before training, 65% (74/114) during training and 70% (63/90) after training, while that of fourth-year residents who did not undergo training was 52% (47/90) (P = 0.04). Fourth-year residents who did not undergo ultrasound training demonstrated similar baseline accuracy to that of third-year residents pretraining (52% (47/90) vs 55% (53/96), P = 0.68), but had significantly lower accuracy than had the third-year residents post-training (52% (47/90) vs 70% (63/90); P = 0.01). Multivariable analysis revealed a positive association between ultrasound feedback training and the ability to assess accurately fetal head position. After adjusting for the variables included in the final model, examinations performed by third-year residents pretraining and those performed by fourth-year residents who did not undergo training were less likely to be accurate than those performed by third-year residents post-training (adjusted odds ratio, 0.48 (95% CI, 0.26-0.91) and 0.42 (95% CI, 0.22-0.80), respectively).

CONCLUSION

Immediate ultrasound feedback training increased trainee accuracy in vaginal assessment of fetal head position in labor. Its integration into obstetric training programs should be considered. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

The use of a hybrid mannequin for the modern high-fidelity simulation in the labor ward: the Italian experience of the Ecografia Gestione Emergenze Ostetriche (EGEO) group

Regular training in the management of intrapartum emergencies has been demonstrated to yield measurable benefits in terms of maternal and perinatal outcomes. Thanks to technologic advances, computerized, full-body mannequins have been created and made available for high-fidelity simulation in obstetrics. The technical skills subjected to training are conventionally represented by classical manual maneuvers, which are recommended in the case of instrumental vaginal delivery, shoulder dystocia, or postpartum hemorrhage. During the past few years, manual skills in the labor ward have been increasingly supported by the use of ultrasound, and this has substantially altered the practical management of intrapartum emergencies in real life. Based on this, a new generation of mannequins suitable for both clinical maneuvers and ultrasound examination seems to be the most appropriate tool for the modern high-fidelity simulation in the management of intrapartum complications. The use of these new hybrid clinical ultrasound mannequins may usher in a new era in high-fidelity obstetric simulation and can hopefully optimize the competencies and technical skills of labor ward professionals in the management of obstetric emergencies. It is from this background that at the beginning of 2018, the Ecografia Gestione Emergenze Ostetriche group was founded in Italy. This group has aggregated a multiprofessional labor ward team including obstetricians, midwives, and anesthesiologists under the common philosophy that ultrasound provides an essential added value in the management of obstetric emergencies. Thanks to the use of these mannequins, the multiprofessional Italian Ecografia Gestione Emergenze Ostetriche group has started to run practical workshops to promote the culture of extraordinary synergy of ultrasound and clinical skills as the best approach to handle intrapartum complications.

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

BACKGROUND

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.

OBJECTIVE

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.

STUDY DESIGN

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.

RESULTS

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.

CONCLUSION

Transabdominal and transperineal intrapartum ultrasound parameters can predict the likelihood of spontaneous vaginal delivery in nulliparous women with prolonged second stage of labor.

Operative vacuum vaginal delivery: effect of compliance with recommended checklist

PURPOSE

Even if the prerequisites and the technique of vacuum extraction are largely established, the role of a checklist in this field has not been tested. To evaluate the role of a checklist implementation on the compliance with the recommended rules in operative vacuum vaginal delivery (OVD) and on maternal and perinatal outcomes.

MATERIALS AND METHODS

Retrospective cohort study on OVD between January 2012 and December 2015 at two hospitals with a tradition of teaching of OVD. A checklist for OVD was introduced in 2014. Three rules had to be recorded: fetal head station and position determination, no more than four tractions, and no more than three cup applications. Adverse maternal outcomes included third- and fourth-degree perineal tears. Adverse neonatal outcome included asphyxia, need for neonatal resuscitation, NICU admission, major head injuries, scalp injuries, and bone or brachial plexus injuries.

RESULTS

Introduction of a checklist for OVD resulted in an increase in the compliance with the rules (83.3 versus 62.8%, p < .001). Cases in which the rules were respected had lower incidence of third- and fourth-degree perineal lacerations after controlling for episiotomy, nulliparity, and indication for OVD (OR = 0.4, 95% CI 0.18-0.89), but similar rates of failure of OVD (2.1 versus 2.2%, p = 1) and adverse neonatal outcome (10.8 versus 11.7%, p=.71).

CONCLUSION

Knowledge and documented compliance with a checklist of recommended rules in OVD may assist in achieving a lower rate of severe perineal and anal sphincter injury but does not alter the success of the procedure or neonatal outcome.

A simple sonographic finding is associated with a successful vacuum application: the fetal occiput or forehead sign

BACKGROUND

Intrapartum ultrasound scanning has been proposed as an ancillary tool in the decision-making process of instrumental vaginal delivery.

OBJECTIVE

The purpose of this study was to evaluate the correlation between the sonographic visualization with a transperineal scan of the fetal occiput or forehead distal to the pubic symphysis with anterior or posterior presentation, respectively (fetal occiput or forehead sign), and the outcome of a vacuum delivery.

STUDY DESIGN

We conducted a retrospective cohort study of patients who underwent a vacuum application in our hospital from 2011-2017, excluding outlet applications. In each case, a preliminary transperineal scan was performed to confirm fetal presentation and position and to demonstrate the presence or absence of the fetal occiput or forehead sign. The head direction, angle of progression, and the head perineum distance were also noted. The primary outcome measure was the success of the vacuum. The secondary outcome measures included fetal complications and perineal lacerations.

RESULTS

A total of 196 consecutive patients were enrolled in the study. The occiput or forehead sign was present in 150 and was associated with a successful vaginal extraction in all cases. Of the 46 cases without the sign, 5 babies (10.8%) were delivered by cesarean section after a failed vacuum (P=.0006). The occiput or forehead sign was also associated with fewer grade 3-4 perineal lacerations (10.7% vs 35.7%; P=.0005) and cephalohematomas, although the difference was not statistically significant (1.4% vs 4.3%). There was a good correlation between the occiput or forehead sign and the other sonographic methods that previously had been proposed to predict a successful vacuum extraction, such as head direction, angle of progression, and head perineum distance.

CONCLUSION

In our hands, the fetal occiput or forehead sign was associated strongly with successful vacuum application and with a very low rate of maternal and fetal complications.