Perinatal and maternal morbidity and mortality among term singletons following midcavity operative vaginal delivery versus caesarean delivery

Variation in Episiotomy Use Among Nulliparous Individuals by Maternity Care Provider and Associated Rates of Obstetric Anal Sphincter Injury

OBJECTIVES

To quantify variation in the association between episiotomy and obstetric anal sphincter injury (OASI) by maternity care provider in spontaneous and operative vaginal deliveries (SVDs and OVDs).

METHODS

Population-based retrospective cohort study of vaginal, term deliveries among nullipara in Canada (2004-2015). Adjusted rate ratios (ARRs) and 95% CIs were estimated using log-binomial regression to quantify the associations between episiotomy and OASI, stratified by care provider (obstetrician [OB], family physician [FP], or registered midwife [RM]) while adjusting for potential confounders.

RESULTS

The study included 631 642 deliveries. Episiotomy use varied by provider: among SVDs, the episiotomy rate was 19.6%, 14.4%, and 8.4% in the OB, FP, and RM groups, respectively. The rate of OASI was higher among SVDs with versus without episiotomy (5.8% vs 4.6%). Conversely, OASI occurred less frequently in operative vaginal deliveries with episiotomy (15.3%) compared with those without (16.7%). In all provider groups, the ARR for OASI was increased with episiotomy in SVD and decreased with episiotomy with forceps delivery. No differences in these associations were observed by provider except among vacuum delivery (ARR with episiotomy vs. without, OB: 0.88, 95% CI 0.84-0.92; FP: 0.89, 95% CI 0.83-0.96, RM: 1.22, 95% CI 1.02-1.48).

CONCLUSIONS

In nullipara, irrespective of maternity care provider, there is a positive association between episiotomy and OASI among SVDs and an inverse association between episiotomy and deliveries with forceps. The relationship between episiotomy and OASI is modified by maternity care providers among vacuum deliveries.

Severe neonatal birth injury: Observational study of associations with operative, cesarean, and spontaneous vaginal delivery

AIM

To determine the association of successful and unsuccessful operative vaginal delivery attempts with risk of severe neonatal birth injury.

METHODS

We conducted a population-based observational study of 1 080 503 births between 2006 and 2019 in Quebec, Canada. The main exposure was operative vaginal delivery with forceps or vacuum, elective or emergency cesarean with or without an operative vaginal attempt, and spontaneous delivery. The outcome was severe birth injury, including intracranial hemorrhage, brain and spinal damage, Erb's paralysis and other brachial plexus injuries, epicranial subaponeurotic hemorrhage, skull and long bone fractures, and liver, spleen, and other neonatal body injuries. We determined the association of delivery mode with risk of severe birth injury using adjusted risk ratios (RR) and 95% confidence intervals (CI).

RESULTS

A total of 8194 infants (0.8%) had severe birth injuries. Compared with spontaneous delivery, vacuum (RR 2.98, 95% CI 2.80-3.16) and forceps (RR 3.35, 95% CI 3.07-3.66) were both associated with risk of severe injury. Forceps was associated with intracranial hemorrhage (RR 16.4, 95% CI 10.1-26.6) and brain and spinal damage (RR 13.5, 95% CI 5.72-32.0), while vacuum was associated with epicranial subaponeurotic hemorrhage (RR 27.5, 95% CI 20.8-36.4) and skull fractures (RR 2.04, 95% CI 1.86-2.25). Emergency cesarean after an unsuccessful operative attempt was associated with intracranial and epicranial subaponeurotic hemorrhage, but elective and other emergency cesareans were not associated with severe injury.

CONCLUSIONS

Operative vaginal delivery and unsuccessful operative attempts that result in an emergency cesarean are associated with elevated risks of severe birth injury.

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

BACKGROUND

During the second stage of labor, in case of a need for a fetal extraction at midcavity, the choice of attempting the procedure between operative vaginal delivery and cesarean delivery is difficult. Moreover, guidelines on this subject are not clear.

OBJECTIVE

This study aimed to identify antenatal and intrapartum parameters associated with a failed midcavity vacuum-assisted delivery and its association with maternal and neonatal adverse outcomes.

STUDY DESIGN

This was a single-center, retrospective, cohort study conducted at a tertiary maternity hospital in France from January 2010 to December 2020. Women with singleton pregnancies under epidural analgesia with nonanomalous cephalic presenting fetuses and gestational ages at ≥37 weeks of gestation, who were submitted to midcavity vacuum-assisted delivery, were included. Following the American College of Obstetricians and Gynecologists definition, midcavity was defined as the presenting part of the fetus (ie, the fetal head) found at stations 0 and +1. For research purposes, all patients were submitted to transperineal ultrasound to evaluate the head-to-perineum distance, however, this measurement did not affect the decision to perform a midcavity vacuum-assisted delivery. The primary outcome of the study was failed midcavity vacuum-assisted delivery leading to cesarean delivery or the use of a different instrument to achieve vaginal delivery.

RESULTS

Overall, 951 cases of midcavity vacuum-assisted delivery were included in this study. Failed midcavity vacuum-assisted delivery occurred in 242 patients (25.4%). Factors independently associated with failed midcavity vacuum-assisted delivery included maternal height (adjusted odds ratio, 0.96; 95% confidence interval, 0.94-0.99; P=.002), duration of the active phase of the first stage of labor (adjusted odds ratio, 1.11; 95% confidence interval, 1.05-1.17; P<.001), nonocciput anterior fetal head position (adjusted odds ratio, 1.47; 95% confidence interval, 1.06-2.04; P=.02), z score of the head-to-perineum distance (adjusted odds ratio, 1.23; 95% confidence interval, 1.05-1.43; P=.01), and birthweight of >4000 g (adjusted odds ratio, 2.04; 95% confidence interval, 1.28-3.26; P=.003). Women submitted to a failed midcavity vacuum-assisted delivery were more likely to have a major postpartum hemorrhage (7.1% vs 2.0%; P<.001), whereas neonates were more likely to have an umbilical artery pH of <7.1 (30.5% vs 19.8%; P=.001), be admitted to the neonatal intensive care unit (9.6% vs 4.7%; P=.005), and have a severe caput succedaneum (14.9% vs 0.7%; P<.001). Subgroup analysis on all patients with a fetal head station of 0 found that the head-to-perineum distance was the only independent variable associated with failed midcavity vacuum-assisted delivery (adjusted odds ratio, 1.66; 95% confidence interval, 1.29-2.12; P<.001). The area under the receiving operating characteristic curve of the head-to-perineum distance in this subgroup population was 0.67 (95% confidence interval, 0.60-0.73; P<.001), and the optimal cutoff point of the head-to-perineum distance measurement discriminating between failed and successful midcavity vacuum-assisted deliveries was 55 mm. It was associated with a 0.90 (95% confidence interval, 0.83-0.95) sensitivity, 0.19 (95% confidence interval, 0.14-0.25) specificity, 0.36 (95% confidence interval, 0.30-0.42) positive predictive value, and 0.80 (95% confidence interval, 0.66-0.90) negative predictive value.

CONCLUSION

Study data showed that a high fetal head station, measured using the head-to-perineum distance, and a nonocciput anterior position of the fetal head are independently associated with failed midcavity vacuum-assisted delivery. The result supported the systematic assessment of the sonographic head station and position before performing a midcavity vacuum-assisted delivery.

Can We Predict Feto-Maternal Adverse Outcomes of Vacuum Extraction?

Introduction Vacuum extraction (VE) is an important modality in modern obstetrics, yet sometimes results in maternal or neonatal adverse outcomes, which can cause a lifetime disability. We aimed to characterize potential risk factors for adverse outcomes that in retrospect would have led the physician to avoid the procedure. Materials and Methods Retrospective cohort of 3331 singleton pregnancies, ≥ 34 w delivered by VE. 263 deliveries (7.9%) incurred a VE-related feto-maternal adverse outcome, defined as one or more of the following: 3-4th-degree perineal laceration, subgaleal hematoma, intracranial hemorrhage, shoulder dystocia, clavicular fracture, Erb's palsy or fracture of humerus. 3068 deliveries (92.1%) did not have VE-related adverse outcomes. Both groups were compared to determine potential risk factors for VE adverse outcomes. Results Multivariable regression found seven independent risk factors for VE-related feto-maternal adverse outcomes: Nulliparity - with an odds ratio (OR) of 1.82 (95% CI = 1.11-2.98, p = 0.018), epidural anesthesia (OR 1.99, CI = 1.42-2.80, p < 0.001), Ventouse-Mityvac (VM) cup (OR 1.86, CI = 1.35-2.54, p < 0.001), prolonged second stage as indication for VE (OR 1.54, CI = 1.11-2.15, p = 0.010), cup detachment (OR 1.66, CI = 1.18-2.34, p = 0.004), increasing procedure duration (OR 1.07 for every additional minute, CI = 1.03-1.11, p < 0.001) and increasing neonatal birthweight (OR 3.42 for every additional kg, CI = 2.33-5.02, p < 0.001). Occiput anterior (OA) position was a protective factor (OR 0.62, CI = 0.43-0.89, p = 0.010). Conclusions VE-related adverse outcomes can be correlated to clinical characteristics, such as nulliparity, epidural anesthesia, VM cup, prolonged second stage as indication for VE, cup detachment, prolonged procedure duration and increasing neonatal weight. OA position was a protective factor. This information may assist medical staff to make an informed decision whether to choose VE or cesarean delivery (CD).

Traction force profile in children with severe perinatal outcomes delivered with a digital vacuum extraction handle: A case-control study

INTRODUCTION

During the second stage of labor, vacuum-assisted delivery is an alternative to forceps delivery and emergency cesarean section. Extensive research concerning perinatal outcomes has indicated that the risk of complications, although rare, is higher than with a spontaneous vaginal delivery. An important factor related to perinatal outcomes is the traction force applied. Our research group previously developed a digital extraction handle, the Vacuum Intelligent Handle-3 (VIH3), that measures and records traction force. The objective of this study was to compare traction force profiles in children with and without severe perinatal outcomes delivered with the digital handle. A secondary aim was to establish a safe force limit.

MATERIAL AND METHODS

This was an observational case-control study at the delivery ward at Karolinska University Hospital, Sweden. In total, 573 children delivered with the digital handle between 2012 and 2018 were included. Cases were defined as a composite of severe perinatal outcomes, including subgaleal hematoma, intracranial hemorrhage, hypoxic ischemic encephalopathy 1-3, seizures or death. The cases in the cohort were matched 1:3 based on five matching variables. Traction profiles were analyzed using the MATLAB® software and conditional logistic regression.

RESULTS

The incidence of severe perinatal outcomes was 2.3%. The 13 cases were matched with three controls each (n = 39). A statistically significant increased odds for higher total traction forces was seen in the case group (odds ratio [OR] 1.004; 95% confidence interval [CI] 1.001-1.007) and for the peak force (OR 1.022; 95% CI 1.004-1.041). Several procedure-related parameters were significantly increased in the case group. As expected, some neonatal characteristics also differed significantly. An upper force limit of 343 Newton minutes (Nmin) revealed an 86% reduction in severe perinatal outcomes (adjusted OR 0.14; 95% CI 0.04-0.5).

CONCLUSIONS

Children with severe perinatal outcomes had traction force profiles with significantly higher forces. The odds for severe perinatal outcomes increased for every increase in Nmin and Newton used during the extraction procedure. A calculated total force level of 343 Nmin is suggested as an upper safety limit, but this must be tested prospectively to provide validity.

Do doctors preferring forceps encounter more obstetric anal sphincter injuries: A retrospective analysis

BACKGROUND

Obstetric anal sphincter injuries (OASIS) is a hospital-acquired injury and can affect a woman's quality of life with problems such as anal incontinence, perineal pain, dyspareunia, mental health, psychosexual issues, and concerns about future childbirth choices.

AIMS

The aim of this study was to determine whether there is a correlation between a doctor's preference for instruments, their individual OASIS rate and whether factors such as their fully dilated caesarean section rate, rate of double instrumental and seniority, influences their individual rate of OASIS.

MATERIALS AND METHODS

A population-based retrospective cohort study was performed on 1340 term nulliparous women with singleton pregnancies who underwent an instrumental delivery or fully dilated caesarean section. A survey of doctors involved in these deliveries was performed. The risk of OASIS was analysed for maternal age, ethnicity, birth position, level of training and doctor's instrument preference using a generalised linear mixed model. Doctors' instrument preferences were established in two ways: a self-reported survey and data-inferred preference based on the most used instrument per doctor. The OASIS rate for individual doctors was calculated.

RESULTS

The overall risk of OASIS is higher for forceps compared to vacuum deliveries. Doctors with a preference for forceps compared to vacuum, correlated with both a lower OASIS rate and a higher fully dilated caesarean section rate.

CONCLUSIONS

Doctors preferring forceps report a lower OASIS and higher fully dilated caesarean section rate. Doctors preferring vacuum must consider carefully whether forceps should follow if a vacuum fails as OASIS is more likely to occur.

Maternal and neonatal trauma following operative vaginal delivery

Background:

Operative vaginal delivery (OVD) is considered safe if carried out by trained personnel. However, opportunities for training in OVD have declined and, given these shifts in practice, the safety of OVD is unknown. We estimated incidence rates of trauma following OVD in Canada, and quantified variation in trauma rates by instrument, region, level of obstetric care and institutional OVD volume.

Methods:

We conducted a cohort study of all singleton, term deliveries in Canada between April 2013 and March 2019, excluding Quebec. Our main outcome measures were maternal trauma (e.g., obstetric anal sphincter injury, high vaginal lacerations) and neonatal trauma (e.g., subgaleal hemorrhage, brachial plexus injury). We calculated adjusted and stabilized rates of trauma using mixed-effects logistic regression.

Results:

Of 1 326 191 deliveries, 38 500 (2.9%) were attempted forceps deliveries and 110 987 (8.4%) were attempted vacuum deliveries. The maternal trauma rate following forceps delivery was 25.3% (95% confidence interval [CI] 24.8%–25.7%) and the neonatal trauma rate was 9.6 (95% CI 8.6–10.6) per 1000 live births. Maternal and neonatal trauma rates following vacuum delivery were 13.2% (95% CI 13.0%–13.4%) and 9.6 (95% CI 9.0–10.2) per 1000 live births, respectively. Maternal trauma rates remained higher with forceps than with vacuum after adjustment for confounders (adjusted rate ratio 1.70, 95% CI 1.65–1.75) and varied by region, but not by level of obstetric care.

Interpretation:

In Canada, rates of trauma following OVD are higher than previously reported, irrespective of region, level of obstetric care and volume of OVD among hospitals. These results support a reassessment of OVD safety in Canada.

Prospective assessment of vacuum deliveries from midpelvic station in a tertiary care university hospital: Frequency, failure rates, labor characteristics and maternal and neonatal complications

BACKGROUND

Midpelvic vacuum extractions are controversial due to reports of increased risk of maternal and perinatal morbidity and high failure rates. Prospective studies of attempted midpelvic vacuum outcomes are scarce. Our main aims were to assess frequency, failure rates, labor characteristics, maternal and neonatal complications of attempted midpelvic vacuum deliveries, and to compare labor characteristics and complications between successful and failed midpelvic vacuum deliveries.

STUDY DESIGN

Clinical data were obtained prospectively from all attempted vacuum deliveries (n = 891) over a one-year period with a total of 6903 births (overall cesarean section rate 18.2% (n = 1258). Student's t-test, Mann-Whitney U-test or Chi-square test for group differences were used as appropriate. Odds ratios and 95% confidence intervals are given as indicated. The uni- and multivariable analysis were conducted both as a complete case analysis and with a multiple imputation approach. A p-value of <0.05 was considered statistically significant.

RESULTS

Attempted vacuum extractions from midpelvic station constituted 36.7% (n = 319) of all attempted vacuum extractions (12.9% (n = 891) of all births). Of these 319 midpelvic vacuum extractions, 11.3% (n = 36) failed and final delivery mode was cesarean section in 86.1% (n = 31) and forceps in the remaining 13.9% (n = 5). Successful completion of midpelvic vacuum by 3 pulls or fewer was achieved in 67.1%. There were 3.9% third-degree and no fourth-degree perineal tears. Cup detachments were associated with a significantly increased failure rate (adjusted OR 6.13, 95% CI 2.41-15.56, p< 0.001).

CONCLUSION

In our study, attempted midpelvic vacuum deliveries had relatively low failure rate, the majority was successfully completed within three pulls and they proved safe to perform as reflected by a low rate of third-degree perineal tears. We provide data for nuanced counseling of women on vacuum extraction as a second stage delivery option in comparable obstetric management settings with relatively high vacuum delivery rates and low cesarean section rates.

Prelabor and intrapartum Doppler ultrasound to predict fetal compromise

According to current estimates, over 20% of the 4 million neonatal deaths occurring globally every year are related to intrapartum hypoxic complications that happen as a result of uterine contractions against a background of inadequate placental function. Most of such intrapartum complications occur among apparently uncomplicated term pregnancies. Available evidence suggests that current risk-assessment strategies do not adequately identify many of the fetuses vulnerable to periods of intermittent hypoxia that characterize human labor. In this review, we discuss the data available on Doppler ultrasound for the evaluation of placental function before and during labor in appropriately grown fetuses; we also discuss the current strategies for ultrasound-based risk stratification, the physiology of intrapartum compromise, and the potential future treatments to prevent fetal distress in labor and reduce perinatal complications related to birth asphyxia.

Adverse outcomes in vacuum-assisted delivery after detachment of non-metal cup: a retrospective cohort study

PURPOSE

To evaluate neonatal and maternal outcomes associated with detachment of non-metal vacuum cup during delivery and to identify risk factors for these detachments.

METHODS

This retrospective cohort study included women with singleton pregnancy, who underwent vacuum-assisted vaginal delivery with a non-metal vacuum cup in a single academic institution, January 2014-August 2019. Failed vacuum deliveries were excluded. Primary outcomes were defined as subgaleal hematoma (SGH) and cord blood pH < 7.15. Secondary outcome included other neonatal complications and adverse maternal outcomes. Outcomes were compared between vacuum-assisted deliveries with and without cup detachment during the procedure.

RESULTS

A total of 3246 women had successful VAD and met the inclusion criteria. During the procedure, the cup detached at least once in 665 (20.5%) deliveries and did not detach in 2581 (79.5%). The cup detachment group experienced higher rates of SGH (8.9% vs. 3.5%, p = 0.001) and cord blood pH < 7.15 (9.8% vs. 7.1%, p = 0.03). There were also more neonatal intensive care unit admissions (NICU) (4.4% vs. 2.7%, p = 0.03) and more fetuses with occiput posterior position (70.8% vs. 79.4%, p = 0.001), the vacuum duration was slightly longer (6 ± 3.7 vs. 5 ± 2.9 min) and more neonates had birth weights > 3700 g (14.1% vs, 10.3%, p = 0.006). Interestingly, there were more males in that group (60.6 vs. 54.6, p = 0.005). All these factors remained significant after controlling for potential confounders.

CONCLUSIONS

Vacuum cup detachment has several predictive characteristics and is associated with adverse neonatal outcomes that should be incorporated into decisions made during the procedure.

Association between the number of pulls and adverse neonatal/maternal outcomes in vacuum-assisted delivery

OBJECTIVES

To determine the association between the number of pulls during vacuum-assisted deliver and neonatal and maternal complications.

METHODS

This was a single-center observational study using a cohort of pregnancies who underwent vacuum-assisted delivery from 2013 to 2020. We excluded pregnancies transitioning to cesarean section after a failed attempt at vacuum-assisted delivery. The number of pulls to deliver the neonate was categorized into 1, 2, 3, and ≥4 pulls. We used logistic regression models to investigate the association between the number of pulls and neonatal intensive care unit (NICU) admission and maternal composite outcome (severe perineal laceration, cervical laceration, transfusion, and postpartum hemorrhage ≥500 mL).

RESULTS

We extracted 480 vacuum-assisted deliveries among 7,321 vaginal deliveries. The proportion of pregnancies receiving 1, 2, 3, or ≥4 pulls were 51.9, 28.3, 10.8, and 9.0%, respectively. The crude prevalence of NICU admission with 1, 2, 3, and ≥4 pulls were 10.8, 16.2, 15.4, and 27.9%, respectively. The prevalence of NICU admission, amount of postpartum hemorrhage, and postpartum hemorrhage ≥500 mL were significantly different between the four groups. Multivariable logistic regression analysis found the prevalence of NICU admission in the ≥4 pulls group was significantly higher compared with the 1 pull group (adjusted odds ratio, 3.3; 95% confidence interval, 1.4-7.8). In contrast, maternal complications were not significantly associated with the number of pulls.

CONCLUSIONS

Vacuum-assisted delivery with four or more pulls was significantly associated with an increased risk of NICU admission. However, the number of pulls was not associated with maternal complications.

Obstetric anal sphincter injury following previous vaginal delivery

INTRODUCTION AND HYPOTHESIS

Obstetric anal sphincter injury (OASI) is a debilitating complication of vaginal delivery. The aim of this study was to identify risk factors for OASI in women with a previous vaginal delivery. We further attempted to detect specific risk factors for severe OASI in this subgroup.

METHODS

We conducted a retrospective cohort study between 2003 and 2019. The study group included women who had a singleton, live, vertex, vaginal delivery at term and who also had at least one previous vaginal delivery. The control group included women with at least one previous vaginal delivery without OASI. General medical history, obstetric history, and ante-, intra- and post-partum data were collected and compared between groups.

RESULTS

Following implementation of the inclusion criteria, 79,176 women were included. Allocation to study groups was according to OASI occurrence: 135 patients (0.2%) had a third- or fourth-degree perineal tear, while 79,041 patients (99.8%) had no such injury. Multivariate analysis revealed that one previous vaginal delivery, birthweight ≥ 3900 g (90th percentile), vacuum-assisted vaginal delivery and episiotomy were associated with increased risk of OASI. Comparison of more severe OASI (3C and 4th-degree) cases to the control group showed similar results with the addition of prolonged second stage and younger age to risk factors associated with severe OASI while episiotomy was no longer significant.

CONCLUSION

In women with a previous vaginal delivery, one vs. two or more previous vaginal deliveries, increased birthweight, vacuum-assisted vaginal delivery and episiotomy are risk factors for OASI.

Antenatal and intrapartum consent: Implications of the NSW Consent Manual 2020

The provision of informed consent for antenatal and intrapartum care remains a contentious issue among healthcare professionals and has been the topic of controversies in the pages of this journal. Recently, the New South Wales (NSW) Department of Health has fundamentally changed the ground rules for the provision of maternity care within the state. In this opinion piece, we try to provide guidance to clinicians to help them deal with the medicolegal environment created by this document which is likely to affect practitioners not just in NSW.

Incidence of second-stage (fully dilated) cesarean sections and how best to represent it: A multicenter analysis

OBJECTIVE

To gather multicenter data on the incidence of second-stage cesarean sections and suggest alternative methods by which the data can be represented.

METHODS

Retrospective, observational study over a 12-month study period. Numbers of term, singleton live births were collated from each of six maternity units. Data were separated by mode of delivery-unassisted vaginal birth, assisted (instrumental) vaginal delivery and elective, first-stage, and second-stage cesarean sections. Second-stage cesarean sections were expressed as a proportion of all deliveries, of all laboring women (i.e. excluding elective cesarean sections), and all women who reach full dilatation (i.e. excluding elective and first-stage cesarean sections).

RESULTS

Of the 28 867 deliveries included in the analysis, 493 of these were second-stage cesarean sections. This represented an incidence of 1.7% of all deliveries, 2.0% of all women in labor, and 2.5% of all women who reach full dilatation.

CONCLUSION

Second-stage cesarean sections continue to be common. Safe delivery of a deeply impacted fetal vertex is essential in modern obstetric practice.

Perinatal outcome after vacuum assisted delivery with digital feedback on traction force; a randomised controlled study

Background

Low and mid station vacuum assisted deliveries (VAD) are delicate manual procedures that entail a high degree of subjectivity from the operator and are associated with adverse neonatal outcome. Little has been done to improve the procedure, including the technical development, traction force and the possibility of objective documentation. We aimed to explore if a digital handle with instant haptic feedback on traction force would reduce the neonatal risk during low or mid station VAD.

Methods

A two centre, randomised superiority trial at Karolinska University Hospital, Sweden, 2016–2018. Cases were randomised bedside to either a conventional or a digital handle attached to a Bird metal cup (50 mm, 80 kPa). The digital handle measured applied force including an instant notification by vibration when high levels of traction force were predicted according to a predefined algorithm. Primary outcome was a composite of hypoxic ischaemic encephalopathy, intracranial haemorrhage, seizures, death and/or subgaleal hematoma. Three hundred eighty low and mid VAD in each group were estimated to decrease primary outcome from six to 2 %.

Results

After 2 years, an interim analyse was undertaken. Meeting the inclusion criteria, 567 vacuum extractions were randomized to the use of a digital handle (n = 296) or a conventional handle (n = 271). Primary outcome did not differ between the two groups: (2.7% digital handle vs 2.6% conventional handle). The incidence of primary outcome differed significantly between the two delivery wards (4% vs 0.9%, p < 0.05). A recalculation of power revealed that 800 cases would be needed in each group to show a decrease in primary outcome from three to 1 %. This was not feasible, and the study therefore closed.

Conclusions

The incidence of primary outcome was lower than estimated and the study was underpowered. However, the difference between the two delivery wards might reflect varying degree of experience of the technical equipment. An objective documentation of the extraction procedure is an attractive alternative in respect to safety and clinical training. To demonstrate improved safety, a multicentre study is required to reach an adequate cohort. This was beyond the scope of the study.

Trial registration

ClinicalTrials.gov NCT03071783, March 1, 2017, retrospectively registered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-03604-z.

Mid forceps did not cause "compromised babies" - "compromise" caused forceps: an approach toward safely lowering the cesarean delivery rate

OBJECTIVE

Over 5 decades, Cesarean Delivery rates (CDR) have risen 6-fold while vaginal operative deliveries [VODs] decreased from >20% to ∼3%. Poor outcomes (HIE and cerebral palsy) haven't improved. Potentiating the virtual abandonment of forceps (F), particularly midforceps (Mid), were allegations about various poor neonatal outcomes. Here, we evaluate VOD and CDR outcomes controlling for prior fetal risk metrics (PR) ascertained an hour before birth.

METHODS

Our 45-year-old database from a labor research unit of moderate/high risk laboring patients (288 NSVDs, 120 Lows, 30 Mids, and 32 CDs) had multiple fetal scalp samples for base excess (BE), pH, cord blood gases (CB), and umbilical artery bloods. ANOVA established relationships between birth methods and outcomes (Cord blood BE and pH and 1 and 5 min Apgar scores); correlations, and two-step multiple regression assessed PR for delivery method and neonatal outcomes. The main outcome measures were correlations of outcome measures with fetal scalp sample BE and pH up to an hour before delivery and fetal reserve index scores scored concurrently.

RESULTS

NSVDs had the best immediate neonatal outcomes with significantly higher CB pH and BE as compared to forceps and CDs. However, controlling for PR revealed: (1) PR at 1 h before delivery correlated with delivery mode, i.e. the decrements in outcomes were already present before the delivery was performed; and (2) The presumed deleterious effects of interventional deliveries, per se, were significantly reduced, and (3) Fetal Reserve Index predicted neonatal outcomes better than fetal scalp sample BE, pH, or delivery mode.

CONCLUSION

The historical belief that MF deliveries caused poorer outcomes than NSVDs seems mostly backwards. Appreciating PR's impact on delivery routes, and when appropriate, properly performing VODs could safely reduce CDR. If our approach lowered CDR by only ∼2%, in the United States about 80,000 CDs might be avoided, saving ∼$750 Million yearly. In the post pandemic world, safely apportioning medical expenses will be even more critical than previously.

Short statured primigravidae: Options for the obstetric management from a survey of UK obstetricians

OBJECTIVE

To assess the current antenatal and intrapartum management options for primigravid women of short stature with a clinically large fetus by a survey of UK Obstetricians.

STUDY DESIGN

An online survey comprised of 15 questions including the options on timing and mode of delivery, counselling about the risk of long-term pelvic floor morbidity following spontaneous vaginal and instrumental deliveries, choice of instruments and the role of episiotomy. The survey was sent to the participants as a part of Royal College of Obstetricians and Gynaecologists (RCOG) Newsletter between September 2017 to October 2018. The scenario described was of a primigravid short stature woman (i.e. height of 160 cm or less) who presents with a clinically large fetus at 38 weeks gestation.

RESULTS

424 Obstetricians participated in the survey. The participation ratio cannot be identified as the survey was emailed as a part of the RCOG Newsletter. Sixty five percent respondents stated that they would scan for estimated fetal weight, 48 % would offer induction of labour at 40 weeks and 14 % would offer an elective/planned caesarean section (CS) at 39-40 weeks. Fifty nine percent would discuss all these risks: obstructed labour, shoulder dystocia, instrumental delivery and obstetric anal sphincter injury (OASI). 73 % would not discuss the long-term risks of urinary and/or faecal incontinence and pelvic organ prolapse. In the presence of failure to progress in the second stage of labour, 69 % would attempt a rotational instrumental delivery and 5% would offer a caesarean section. Manual rotation and 'straight' forceps application were the most frequent type of rotational delivery, followed by Ventouse and Kiellands forceps. Thirty four percent stated that they do not routinely perform an episiotomy in this scenario. Seventy three percent stated that their choice of instrument was not based on the long-term risk of urinary and faecal incontinence.

CONCLUSION

The results suggest that 40 % of the respondents would not discuss all of the complications after vaginal delivery in women of short stature. The most common delivery option would be vaginal delivery.

Risk factors for obstetric anal sphincter injury among parous women

PURPOSE

Nulliparity and operative vaginal delivery are established risk factor for obstetric anal sphincter injury (OASI). However, risk factors for OASIS occurrence among parous women delivering vaginally are not well-established. We aimed to study the risk factors for OASI occurrence among parous women.

METHODS

A retrospective study including all parous women who delivered vaginally at term during 2011-2019 at a university hospital. Deliveries of parous women with OASI were compared to deliveries without OASI. The risk factors associated with OASI were investigated.

RESULTS

Overall, 35,397 women were included in the study with an OASI rate of 0.4% (n = 144). A higher rate of only one previous vaginal delivery was noted in the OASI group (78.5% vs. 46.4%, OR [95% CI] 4.20, 2.82-6.25, p < 0.001). The rate of vacuum-assisted deliveries was comparable between the study groups. The median birth weight was higher among the OASI group (3566 vs. 3300 g, p < 0.001), as was the rate of macrosomic neonates (19.4% vs. 5.5%, OR [95% CI] 4.15, 2.74-6.29, p < 0.001). On multivariate logistic regression analysis, only two factors were independently positively associated with the occurrence of OASI: a history of only one previous vaginal delivery (adjusted OR [95% CI] 4.34, 2.90-6.49, p = 0.001), and neonatal birth-weight (for each 500 g increment) (adjusted OR [95% CI] 2.51, 1.84-3.44, p < 0.001).

CONCLUSIONS

Among parous women, the only factors found to be independently positively associated with OASI were the order of parity and neonatal birth-weight. Vacuum-assisted delivery was not associated with an increased risk of OASI among parous women.

Episiotomy use among vaginal deliveries and the association with anal sphincter injury: a population-based retrospective cohort study

BACKGROUND

The rate of obstetric anal sphincter injury has increased in recent years, particularly among operative vaginal deliveries. We sought to characterize temporal trends in episiotomy use and to quantify the association between episiotomy and obstetric anal sphincter injury.

METHODS

Using a population-based retrospective cohort study design of hospital data from 2004 to 2017, we studied all vaginal deliveries of singleton infants at term gestation in Canada (excluding Quebec). Rates of obstetric anal sphincter injury were contrasted between women who had an episiotomy and those who did not. Log-binomial regression was used to estimate the association between episiotomy and obstetric anal sphincter injury among women with spontaneous and operative vaginal deliveries after controlling for confounders.

RESULTS

The study population included 2 570 847 deliveries. Episiotomy use declined significantly among operative vaginal deliveries (53.1% in 2004 to 43.2% in 2017, p < 0.0001) and spontaneous vaginal deliveries (13.5% in 2004 to 6.5% in 2017, p < 0.0001). Episiotomy was associated with higher rates of obstetric anal sphincter injury among spontaneous vaginal deliveries (4.8 with episiotomy v. 2.4% without; adjusted rate ratio [RR] 2.06, 95% confidence interval [CI] 2.00-2.11) and this association remained after stratification by parity and obstetric history. In contrast, episiotomy was associated with lower rates of obstetric anal sphincter injury among forceps deliveries in nulliparous women (adjusted RR 0.63, 95% CI 0.61-0.66), and women with vaginal birth after cesarean (adjusted RR 0.71, 95% CI 0.60-0.85), but not among parous women without a previous cesarean (adjusted RR 1.16, 95% CI 1.00-1.34).

INTERPRETATION

Episiotomy use has declined in Canada for all vaginal deliveries. The protective association between episiotomy and obstetric anal sphincter injury among women who gave birth by operative vaginal delivery (especially forceps) warrants reconsideration of clinical practice among nulliparous women and those attempting vaginal birth after cesarean.

Babies in occiput posterior position are significantly more likely to require an emergency cesarean birth compared with babies in occiput transverse position in the second stage of labor: A prospective observational study

Introduction

Malposition complicates 2‐13% of births at delivery, leading to increased obstetric interventions (cesarean section and instrumental delivery) and higher rates of adverse fetal and maternal outcomes. Limited data are available regarding the likely rates of obstetric intervention and subsequent neonatal and maternal outcomes of births with babies in persistent occiput posterior position vs those in persistent occiput transverse position. The UK Audit and Research trainee Collaborative in Obstetrics and Gynecology (UK‐ARCOG) network set out to collect data prospectively at delivery on final mode of delivery and immediate outcomes.

Material and methods

The UK‐ARCOG network collected data on all births with malposition of the fetal head complicating the second stage of labor (n = 838) (occiput posterior/occiput transverse) requiring rotational vaginal operative birth or emergency cesarean to expedite delivery across 66 participating UK National Health Service maternity units over a 1‐month period. The outcomes considered were the need for emergency cesarean section without a trial of instrumental delivery, success of the first method of delivery employed in achieving a vaginal delivery and neonatal/maternal outcomes.

Results

Obstetricians regarded assistance with an operative vaginal delivery method to be unsafe in 15% of babies in occiput posterior position and 6.1% of babies in occiput transverse position, and they were delivered by primary emergency cesarean section. When vaginal delivery was deemed safe (defined as attempted assisted vaginal rotational delivery), the first instrument attempted was successful in 74.4% of occiput posterior babies and 79.3% of occiput transverse babies.

Conclusions

Our data facilitates decision making by obstetricians to increase safety of assisted rotational operative delivery of a malpositioned baby at initial assessment and in counseling women. Until data from a well‐designed randomized controlled trial of instrumental delivery vs emergency cesarean section are available, this manuscript provides contemporaneous national data from a high resource setting within a structured training program, to assist the selection of an appropriate instrument/method for the delivery of a malpositioned baby.

Resident Attitudes Towards Caesarean Delivery in Canadian Obstetrics and Gynaecology Residency Programs

OBJECTIVE

This study aimed to explore the attitudes of obstetrics and gynaecology residents in Canada towards interventions that influence caesarean section rates. The study looked at residents' attitudes towards four guidelines that support vaginal and assisted delivery (vaginal birth after caesarean section, induction of labour, operative vaginal birth, and fetal health surveillance in labour) and towards Society of Obstetricians and Gynaecologists of Canada (SOGC) guidelines in general. The study also sought to investigate whether these attitudes vary by residency training location.

METHODS

An online survey of obstetrics and gynaecology residents across Canada was conducted. Residents responded to statements derived from guidelines using a five-point attitudinal scale and to an optional long-answer question about how residency has prepared them to make decisions around interventions. Descriptive summary statistics are used to present the findings (Canadian Task Force Classification III).

RESULTS

A total of 27% of residents completed the survey. The majority demonstrated attitudes congruent with guidelines and favourable towards SOGC guidelines in general. Residents attitudes were least favourable towards electronic fetal monitoring, with 67.4% of responses congruent with the guideline. Attitudes were most aligned with the operative vaginal birth guideline, with 87.9% of responses congruent with the guideline. This sample was underpowered to detect statistically significant differences among residency programs, although there was some variation in attitudes across programs, with the most congruent scoring program at 81.8% congruent responses and the lowest at 66.7%.

CONCLUSION

Obstetrics and gynaecology residents in Canada have favourable attitudes towards interventions that support vaginal and assisted delivery. There was variability in observed attitudes across programs, although this was not statistically significant.

Characteristics and changes in characteristics of women and babies admitted to residential parenting services in New South Wales, Australia in the first year following birth: a population-based data linkage study 2000-2012

OBJECTIVE

To examine the characteristics of women and babies admitted to the residential parenting services (RPS) of Tresillian and Karitane in the first year following birth.

DESIGN

A linked population data cohort study was undertaken for the years 2000-2012.

SETTING

New South Wales (NSW), Australia.

PARTICIPANTS

All women giving birth and babies born in NSW were compared with those admitted to RPS.

RESULTS

During the time period there were a total of 1 097 762 births (2000-2012) in NSW and 32 991 admissions to RPS. Women in cohort 1: (those admitted to RPS) were older at the time of birth, more likely to be admitted as a private patient at the time of birth, be born in Australia and be having their first baby compared with women in cohort 2 (those not admitted to an RPS). Women admitted to RPS experienced more birth intervention (induction, instrumental birth, caesarean section), had more multiple births and were more likely to have a male infant. Their babies were also more likely to be resuscitated and have experienced birth trauma to the scalp. Between 2000 and 2012 the average age of women in the RPS increased by nearly 2 years; their infants were older on admission and women were less likely to smoke. Over the time period there was a drop in the numbers of women admitted to RPS having a normal vaginal birth and an increase in women having an instrumental birth.

CONCLUSION

Women who access RPS in the first year after birth are more socially advantaged and have higher birth intervention than those who do not, due in part to higher numbers birthing in the private sector where intervention rates are high. The rise in women admitted to RPS (2000-2012) who have had instrumental births is intriguing as overall rates did not increase.

Risk factors associated with subgaleal hemorrhage in neonates exposed to vacuum extraction

INTRODUCTION

Subgaleal hemorrhage (SGH) is a life-threatening neonatal condition that is strongly associated with vacuum assisted delivery (VAD). The factors associated with the development of SGH following VAD are not well-established. We aimed to evaluate the factors associated with the development of SGH following attempted VAD.

MATERIAL AND METHODS

A retrospective case-control study of women who delivered at a tertiary university-affiliated medical center in Jerusalem, Israel, during 2009-2018. Cases comprised all parturients with singleton pregnancies for whom attempted VAD resulted in neonatal SGH. A control group of VAD attempts was established by matching one-to-one according to gestational age at delivery, parity and year of delivery. Fetal, intrapartum and vacuum procedure characteristics were compared between the groups.

RESULTS

In all, 313 (89.5%) of the 350 attempted VAD were nulliparous. Baseline maternal and fetal characteristics were similar between the groups except for higher neonatal birthweight in the SGH group. In multivariate logistic regression analysis, only six independent risk factors were significantly associated with the development of SGH: second-stage duration (for each 30-minute increase, adjusted odds ratio [OR] 1.13; 95% confidence intervals [CI] 1.04-1.25; P = .006), presence of meconium-stained amniotic fluid (adjusted OR 2.61; 95% CI 1.52-4.48; P = .001), presence of caput succedaneum (adjusted OR 1.79; 95% CI 1.11-2.88; P = .01), duration of VAD (for each 3-minute increase, adjusted OR 2.04; 95% CI 1.72, 2.38; P < .001), number of dislodgments (adjusted OR 2.38; 95% CI 1.66-3.44; P < .001), and fetal head station (adjusted OR 3.57; 95% CI 1.42-8.33; P = .006). Receiver operating characteristic curves showed that VAD duration of ≥15 minutes had a 96.7% sensitivity and 75.0% specificity in predicting SGH formation, with an area under the curve equal to .849.

CONCLUSIONS

Vacuum duration, the number of dislodgments, the duration of second stage of delivery, fetal head station, the presence of caput succedaneum and the presence of meconium were found to be independently associated with SGH formation.

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.

Evaluation of blood type as a potential risk factor for early postpartum hemorrhage

OBJECTIVE

Studies have demonstrated an association between ABO blood type and bleeding status. The aim of this analysis was to determine whether O blood type is associated with higher early postpartum hemorrhage (PPH) risk as compared to other blood types.

STUDY DESIGN

In this retrospective case-control study, data was gathered form 4,516 deliveries occurring at our institution between 2014 and 2016. Cases were categorized into one of two groups according to women's major blood type (O or non-O), and thereafter according to minor blood type (RH positive or negative). The primary outcome was early PPH which was further stratified by clinical severity according to the decrement in hemoglobin concentration after delivery. Categorical variables were compared using the χ2 test while continuous variables were compared using the student's t-test. All data were further analyzed using a stepwise logistic regression model.

RESULTS

1,594 (35.3%) of 4,516 women included in this analysis had O blood type. Early PPH occurred in 44 women (2.7%) with O blood type and 65 women (2.22%) with other blood types. O blood type was not associated with an increased risk for early PPH (OR 1.24, 95% CI 0.84-1.82, P = 0.275). This lack of association remained unchanged after stratification by PPH severity. There was also no significant association between Rh blood type and the risk for early PPH (OR 0.97, 95% CI 0.44-1.4, P = 0.422).

CONCLUSIONS

In this cohort, O blood type was not associated with an increased risk for early PPH.

Vacuum extraction for non-rotational and rotational assisted vaginal birth

Vacuum-assisted birth is a safe mode of birth in the presence of a skilled provider. Vacuum extraction can avoid prolonged second stage of labour, birth asphyxia in the presence of foetal distress or maternal pushing where contraindicated. Vacuum-assisted births - particularly those in midpelvic rotational births - have been increasingly traded for caesarean births, although the latter are generally associated with potentially a greater risk to women and (future) children. In this article, (contra)indications and the basics of vacuum technique are elaborated. A specific section is dedicated to vacuum extraction for rotational birth. If these techniques are known, trained and practiced by obstetric care givers, then vacuum extraction has tremendous potential to make childbirth safer.

Morbidity and Mortality Associated With Forceps and Vacuum Delivery at Outlet, Low, and Midpelvic Station

OBJECTIVE

This study sought to quantify perinatal and maternal morbidity and mortality associated with forceps and vacuum delivery compared with Caesarean delivery in the second stage of labour and to estimate whether these associations differed by pelvic station.

METHODS

The investigators conducted a population-based, retrospective cohort study of term singleton deliveries by operative delivery with prolonged second stage of labour in Canada (2003-2013) using national hospitalization data. The primary study outcomes were severe perinatal morbidity and mortality (i.e., seizures, assisted ventilation, severe birth trauma, and perinatal death) and severe maternal morbidity and mortality (i.e., severe postpartum hemorrhage, cardiac complication, and maternal death). Logistic regression was used to estimate adjusted odds ratios (aOR) and 95% confidence intervals (CI) after stratifying by indication (dystocia or fetal distress). The Breslow-Day chi-square test for heterogeneity in ORs was used to test effect modification by pelvic station (outlet, low, or midpelvic).

RESULTS

There were 61 106 deliveries included in the study. Among women with dystocia, forceps and vacuum deliveries were associated with higher rates of perinatal morbidity and mortality compared with Caesarean delivery (forceps: aOR 1.56; 95% CI 1.13-2.17; vacuum: aOR 1.44; 95% CI 1.06-1.97). Vacuum delivery was associated with lower rates of maternal morbidity and mortality compared with Caesarean delivery (dystocia: aOR 0.64; 95% CI 0.51-0.81; fetal distress: aOR 0.43; 95% CI 0.32-0.57). Pelvic station did not significantly modify the associations between forceps or vacuum and perinatal or maternal morbidity and mortality.

CONCLUSION

Forceps and vacuum delivery is associated with increased rates of severe perinatal morbidity and mortality compared with Caesarean delivery among women with dystocia, whereas vacuum delivery is associated with decreased rates of severe maternal morbidity and mortality.

Ecological association between operative vaginal delivery and obstetric and birth trauma

BACKGROUND

Increased use of operative vaginal delivery (use of forceps, vacuum or other device) has been recommended to address high rates of cesarean delivery. We sought to determine the association between rates of operative vaginal delivery and obstetric trauma and severe birth trauma.

METHODS

We carried out an ecological analysis of term, singleton deliveries in 4 Canadian provinces (2004-2014) using data from the Canadian Institute for Health Information. The primary exposure was mode of delivery. The primary outcomes were obstetric trauma and severe birth trauma.

RESULTS

Data on 1 938 913 deliveries were analyzed. The rate of obstetric trauma was 7.2% in nulliparous women, and 2.2% and 2.7% among parous women without and with a previous cesarean delivery, respectively, and rates of severe birth trauma were 2.1, 1.7 and 0.7 per 1000, respectively. Each 1% absolute increase in rates of operative vaginal delivery was associated with a higher frequency of obstetric trauma among nulliparous women (adjusted rate ratio [ARR] 1.06, 95% confidence interval [CI] 1.05-1.06), parous women without a previous cesarean delivery (ARR 1.10, 95% CI 1.08-1.13) and parous women with a previous cesarean delivery (ARR 1.11, 95% CI 1.07-1.16). Operative vaginal delivery was associated with more frequent severe birth trauma, but only in nulliparous women (ARR 1.05, 95% CI 1.03-1.07). In nulliparous women, sequential vacuum and forceps instrumentation was associated with the largest increase in obstetric trauma (ARR 1.44, 95% CI 1.35-1.55) and birth trauma (ARR 1.53, 95% CI 1.03-2.27).

INTERPRETATION

Increases in population rates of operative vaginal delivery are associated with higher population rates of obstetric trauma, and in nulliparous women with severe birth trauma.

Perinatal and maternal morbidity and mortality among term singletons following midcavity operative vaginal delivery versus caesarean delivery

Objective

To quantify severe perinatal and maternal morbidity/mortality associated with midcavity operative vaginal delivery compared with caesarean delivery.

Design

Population‐based, retrospective cohort study.

Setting

British Columbia, Canada.

Population

Term, singleton deliveries (2004–2014) by attempted midcavity operative vaginal delivery or caesarean delivery in the second stage of labour, stratified by indication for operative delivery (n = 10 901 deliveries; 5057 indicated for dystocia, 5844 for fetal distress).

Methods

Multinomial propensity scores and mulitvariable log‐binomial regression models were used to estimate adjusted rate ratios (ARR) and 95% confidence intervals (95% CI).

Main outcome measures

Composite severe perinatal morbidity/mortality (e.g. convulsions, severe birth trauma and perinatal death) and severe maternal morbidity (e.g. severe postpartum haemorrhage, shock, sepsis and cardiac complications).

Results

Among deliveries with dystocia, attempted midcavity operative vaginal delivery was associated with higher rates of severe perinatal morbidity/mortality compared with caesarean delivery (forceps ARR 2.11, 95% CI 1.46–3.07; vacuum ARR 2.71, 95% CI 1.49–3.15; sequential ARR 4.68, 95% CI 3.33–6.58). Rates of severe maternal morbidity/mortality were also higher following midcavity operative vaginal delivery (forceps ARR 1.57, 95% CI 1.05–2.36; vacuum ARR 2.29, 95% CI 1.57–3.36). Among deliveries with fetal distress, there were significant increases in severe perinatal morbidity/mortality following attempted midcavity vacuum (ARR 1.28, 95% CI 1.04–1.61) and in severe maternal morbidity following attempted midcavity forceps delivery (ARR 2.34, 95% CI 1.54–3.56).

Conclusion

Attempted midcavity operative vaginal delivery is associated with higher rates of severe perinatal morbidity/mortality and severe maternal morbidity, though these effects differ by indication and instrument.

Tweetable abstract

Perinatal and maternal morbidity is increased following midcavity operative vaginal delivery.

Tweetable abstract

Perinatal and maternal morbidity is increased following midcavity operative vaginal delivery.