Rotational Forceps: Which technique is superior for blade insertion? A simulation study comparing direct, first posterior, and wandering maneuvers.

OBJECTIVE: The Kielland's forceps is the most used forceps for assisting rotational operative births. There are various maneuvers described for blade insertion. Among these, the most used ones are the direct, first posterior, and wandering maneuver. The objective of this study was to compare these three maneuvers using a simulator. STUDY DESIGN: In this experimental study, 144 rotational forceps-assisted births were conducted using a simulation model, with 72 starting in a right occiput-transverse position and 72 in a left occiput-transverse position. Each of the three maneuvers (direct, first posterior, or wandering) for blade insertion was performed 48 times by a total of 6 operators, comprising 3 obstetricians with over 10 years of experience and 3 trainees. The assessment of forceps application included evaluating the placement of the blades in terms of asymmetry and the distance from the lock to the posterior fontanelle. Additionally, the study evaluated the number of reinsertions and relocations required, the perceived difficulty of the procedure, and the operator's level of experience. RESULTS: There were no statistically significant differences in terms of asymmetry with the three maneuvers. Regarding the distance from the lock to the posterior fontanelle, the best results were obtained with the direct maneuver. There were no differences in the number of reinsertions, relocations, and the perceived difficulty by the operators among the three maneuvers. Experienced obstetricians had better outcomes in terms of the need for reinsertions. CONCLUSION: The direct maneuver offer advantages in the insertion of blades for rotational forceps.

Join point trends of instrumental vaginal deliveries and cesarean sections at the Lagos University Teaching Hospital, Lagos, Nigeria (2002-2017).

OBJECTIVE: To determine the trends of instrumental vaginal delivery (IVD) and cesarean section (CS) at the Lagos University Teaching Hospital (LUTH), Nigeria, over 16 years, from 2002 to 2017. METHODS: A retrospective cross-sectional study. The case records of all women who had IVD and CS during the study period were reviewed. The trends in the IVD and CS rates were evaluated using join point regression modeling. The average annual percent change (AAPC) and annual percent change (APC) with associated 95% confidence interval of segmental trends were calculated. RESULTS: The overall IVD rate was 1.36%. Vacuum delivery rate was higher than forceps (0.79% vs 0.57%). The CS rate was 44.9 per 100 deliveries; the rate increased by about 3.7% per annum. CS rates were 7.1-89.9 times the IVD rates within the study period. The number of IVDs performed in the hospital declined by about 83.02%, from 53 cases in 2002 to nine cases in 2017. Forceps delivery declined at a faster rate than vacuum delivery between 2002 and 2017 (AAPC for forceps: -12.6% [-17.5 to -7.5], P < 0.001 vs AAPC for vacuum: -6.2% [-14.3 to 2.7], P = 0.200). The commonest indication for IVD was prolonged second stage of labor (47/162, 29.01%) and shortening of the second stage of labor for maternal conditions (47/162, 29.01%). CONCLUSION: IVD rates are low and declining at LUTH. There is need to train accoucheurs on the safe use of IVDs to potentially reduce the CS rate.

A national survey of clinicians' opinions of rotational vaginal births.

INTRODUCTION: Malposition of the fetal head, defined as occiput transverse or posterior positions, occurs in approximately 5% of births. At full cervical dilatation, fetal malposition is associated with an increased risk of rotational vaginal birth. There are three different rotational methods: manual rotation, rotational ventouse or rotational (Kielland's) forceps. In the absence of robust evidence, it is not currently known which of the three methods is most efficacious, and safest for parents and babies. OBJECTIVE: To gain greater insights into opinions and preferences of rotational birth to explore the acceptability and feasibility of performing a randomised trial comparing different rotational methods. MATERIAL AND METHODS: A survey was sent via email to obstetricians from the British Maternal Fetal Medicine Society, as well as expert obstetricians and active academics in ongoing research in the UK. The questions focussed on perceived competence, preferred rotational method, location (theatre or labour room), willingness to recruit to an RCT, and its outcome measures. Closed questions were followed by the option of free text to allow further comments. The free text answers underwent thematic analysis. RESULTS: 252 consultant obstetricians responded. The majority stated they were competent in performing manual rotation (88.1%). Half felt proficient using Kielland's rotational forceps (54.4%). Most obstetricians felt skilled in rotational ventouse (76.2%). Manual rotation was the preferred first rotational method of choice in cases of both occiput transverse and posterior positions. The decision for which rotational method to attempt first was considered case-dependent by many. Two thirds of obstetricians would usually conduct rotational births in theatre (67.9%). Over half (52%) do not routinely use intrapartum ultrasound. Most (62.7%) would be willing to recruit to a randomised controlled trial comparing manual versus instrumental rotation. Over half (57.2%) would be willing to recruit to the same RCT if they were the most senior doctor competent in rotational vaginal birth supervising a junior. CONCLUSION: There is a wide range of practice in conducting rotational vaginal births in the UK. An RCT to investigate the impact of different rotational methods on outcome would be both feasible and desirable, especially in research-active hospitals.

Adjusting models to better predict obstetric anal sphincter injury (OASIS) in forceps-assisted vaginal deliveries: A retrospective cross-sectional trial.

OBJECTIVE: Obesity and maternal age are increasing among pregnant patients. The understood effect of body mass index (BMI), advanced maternal age (AMA), and second stage of labor on obstetric anal sphincter injury (OASIS) at delivery is varied. The objective of this study was to assess whether incorporating BMI, second stage of labor length, and AMA into a model for predicting OASIS among forceps-assisted vaginal deliveries (FAVD) had a higher predictivity value compared to models without these additions. METHOD: This was an IRB-approved retrospective cohort study of singleton gestations who underwent a FAVD between 2017 and 2021. The primary outcome was prediction of OASIS via established models versus models including the addition of new predictive factors. RESULTS: A total of 979 patients met inclusionary criteria and were included in the final analysis. 20.4% of patients had an OASIS laceration, 11.3% of neonates had NICU admissions, 23.7% had a composite all neonatal outcome, and 8% had a composite subgaleal/cephalohematoma outcome. Comparisons of known factors that predict OASIS (nulliparity, race, episiotomy status) to known factors with additional predictors (BMI, AMA, and length of second stage in labor) were explored. After comparing each model's AUC to one another (a total of 3 comparisons made), there was no statistically significant difference between the models (all P > 0.62). CONCLUSION: Including BMI, AMA, and second stage of labor length does not improve the predictivity of OASIS in patients with successful FAVD. These factors should not impact a provider's decision to perform a FAVD when solely considering increased odds of OASIS.

Correlative analysis of different treatments of persistent occipitotransverse position on the outcome for mother and infant.

OBJECTIVE: To explore the clinical feasibility of different treatment methods for persistent occipitotransverse position and the influence on maternal and infant complications. METHOD: During the trial of vaginal delivery from April 2020 to March 2023 in our hospital, the cervix was fully dilated and the presentation was located at +2 station. Ninety-six pregnant women with fetal presentation at +4 station, occipitotransverse fetal position, maternal complications, abnormalities in the second stage of labor, and or fetal distress were divided into two groups: 65 patients with Kielland forceps vaginal delivery and 31 patients underwent emergency cesarean section. The delivery time, vaginal laceration rate, postpartum blood loss volume, puerperal infection rate, neonatal birth injury rate, and neonatal 1 min Apgar scores were analyzed. RESULTS: The delivery outcomes and maternal and neonatal complications of 96 pregnant women were analyzed: the application of Kielland forceps delivery time was shorter, while the vaginal laceration rate, postpartum hemorrhage, puerperal infection rate were significantly lower than that of patients undergoing emergency cesarean section and the neonatal 1 min Apgar score was higher than that of emergency cesarean section group (p < 0.05). CONCLUSION: It was clinically appropriate to use Kielland forceps in vaginal delivery when the persistent occipitotransverse position was present and delivery needed to be expediated. Use of Kielland forceps can shorten the delivery time, improve the success rate of vaginal delivery and reduce the complications of mothers and infants.

Analysis of the obstetrician's posture and movements during a simulated forceps delivery.

BACKGROUND: The objective of this study was to identify and qualify, by means of a three-dimensional kinematic analysis, the postures and movements of obstetricians during a simulated forceps birth, and then to study the association of the obstetricians' experience with the technique adopted. METHOD: Fifty-seven volunteer obstetricians, 20 from the Limoges and 37 from the Poitiers University hospitals, were included in this multi-centric study. They were classified into 3 groups: beginners, intermediates, and experts, beginners having performed fewer than 10 forceps deliveries in real conditions, intermediates between 10 and 100, and experts more than 100. The posture and movements of the obstetricians were recorded between December 2020 and March 2021 using an optoelectronic motion capture system during simulated forceps births. Joint angles qualifying these postures and movements were analysed between the three phases of the foetal traction. These phases were defined by the passage of a virtual point associated with the forceps blade through two anatomical planes: the mid-pelvis and the pelvic outlet. Then, a consolidated ascending hierarchical classification (AHC) was applied to these data in order to objectify the existence of groups of similar behaviours. RESULTS: The AHC distinguished four different postures adopted when crossing the first plane and three different traction techniques. 48% of the beginners adopted one of the two raised posture, 22% being raised without trunk flexion and 26% raised with trunk flexion. Conversely, 58% of the experts positioned themselves in a "chevalier servant" posture (going down on one knee) and 25% in a "squatting" posture before initiating traction. The results also show that the joint movement amplitude tends to reduce with the level of expertise. CONCLUSION: Forceps delivery was performed in different ways, with the experienced obstetricians favouring postures that enabled observation at the level of the maternal perineum and techniques reducing movement amplitude. The first perspective of this work is to relate these different techniques to the traction force generated. The results of these studies have the potential to contribute to the training of obstetricians in forceps delivery, and to improve the safety of women and newborns.

A new course on assisted rotational birth and complex caesarean section - Mixed methods evaluation of Art & Craft.

OBJECTIVES: To assess the utility of Art & Craft - a new, hands-on course on Advanced Rotational Techniques and safe Caesarean biRth at Advanced/Full dilation Training aimed at senior Obstetrics trainees. The aims were to assess whether it improved confidence and skills in rotational vaginal birth, impacted fetal head at caesarean, and ultrasound for fetal position. STUDY DESIGN: With ethical approval, pre- and post- course questionnaires and post- course interviews of attendees were conducted. A pre course questionnaire was emailed 1 week before the course. Attendees were asked to rate their confidence levels in performing vaginal examination and ultrasound assessment of fetal position, rotational ventouse, manual rotation, Kielland's rotational forceps, and disimpaction of the fetal head during second stage caesarean on a scale of 1 to 5. 1 = not confident at all and 5 = very confident. A post-course questionnaire with the same questions was emailed 3 days after. p values for differences in scores were calculated using the Wilcoxon signed rank test using Stata/MP 18 software. RESULTS: 32 trainees attended the course. 28 questionnaires were available for analysis. The majority 39 % were middle grade (ST3-ST5) level. Initial confidence was very low for rotational forceps (median 1/5). After attending the course and practical stations, respondents' confidence levels increased significantly (p < 0.05) across all domains; vaginal examination from 4 to 5, ultrasound for fetal position, rotational ventouse, and manual rotation from 3 to 5, disimpaction from 4 to 4.5, and Kielland's rotational forceps from 1 to 4. Nine participated in post course interviews, which were thematically analysed. Participants expressed that the course gave them the opportunity to ask specific questions from experts to improve their confidence. A barrier to learning new methods was highlighted in that it is difficult to receive practical training in Kielland's, resulting in low confidence. CONCLUSION: A practical, hands-on course on complex operative birth significantly increases trainee confidence levels in vaginal examination, ultrasound for fetal position, disimpaction, and techniques for rotational vaginal birth. The evaluation highlights that continued education and practise is required, even when trainees are senior. Evaluation of clinical outcomes after training is needed; and planned.

Experiencia de parto instrumental con vacuum en Hospital Público de Santiago de Chile / Experience of vacuum-assisted instrumental delivery in a Public Hospital in Santiago, Chile

Introducción: El vacuum es el instrumento de elección para asistir el parto instrumental en países desarrollados. Objetivo: El objetivo del estudio es exponer los resultados maternos y fetales del uso del vacuum en población chilena y promover su disponibilidad y uso en nuestro país y Latinoamérica. Método: El estudio se realizó entre octubre de 2017 y diciembre de 2021, incluyendo a pacientes que tuvieron parto instrumental con vacuum en el Hospital San Juan de Dios de Chile. Se compararon los partos exitosos con vacuum y los partos en los que se requirió el uso de otro instrumento o una cesárea posterior al uso del instrumento. Resultados: Se realizaron 153 vacuum, correspondientes al 28,59% del total de partos instrumentales. El 79,74% tuvo éxito. El 5,88% no recibió anestesia o se aplicó anestesia local. Solo el 3,27% presentó desgarro perineal con compromiso del esfínter anal. El 91,5% de los recién nacidos no tuvieron complicaciones fetales. Un 20,3% requirió reanimación neonatal. Conclusiones: El estudio muestra que el vacuum es una opción segura y efectiva de parto instrumental en nuestra población. La correcta capacitación y protocolos adecuados son necesarios para garantizar resultados exitosos.

Introduction: Vacuum extraction is the instrument of choice for assisting instrumental delivery in developed countries. Objective: The aim of the study is to present the maternal and fetal outcomes of vacuum use in the Chilean population and promote its availability and usage in our country and Latin America. Method: The study was performed between October 2017 and December 2021, including patients who underwent instrumental delivery with a vacuum extraction at the Hospital San Juan de Dios in Chile. Successful vacuum deliveries were compared with deliveries where another instrument was required, or a cesarean section was performed after instrument use. Results: A total of 153 vacuum deliveries were carried out, accounting for 28.59% of all instrumental deliveries. 79.74% were successful. 5.88% did not receive anesthesia or received local anesthesia. Only 3.27% experienced perineal tear with involvement of the anal sphincter. 91.5% of newborns had no fetal complications. 20.3% required neonatal resuscitation. Conclusions: The study demonstrates that the vacuum is a safe and effective option for instrumental delivery in our population. Proper training and appropriate protocols are necessary to ensure successful outcomes.

A systematic review and a meta-analysis on the incidence of obstetric anal sphincter injuries during vaginal delivery.

AIM: The incidence of obstetric anal sphincter injuries (OASIS) has increased in the past two decades despite improved awareness of the risk factors. This study aimed to define the incidence of OASIS in women with different features (instrumental delivery or other variables). METHODS: A systematic review was conducted on articles reporting the incidence of OASIS. This review aims to examine the association of instrumentation and OASIS by performing a formal systematic review of the published literature. Databases used for the research were MEDLINE, Embase, CINAHL and 'Maternity and infant care' databases. RESULTS: Two independent reviewers screened the selected articles. 2326 duplicates were removed from the total of 4907 articles. The remaining 2581 articles were screened for title and abstract. 1913 articles were excluded due to irrelevance. The remaining 300 were screened as full text. Primiparity associated with the use of forceps were the features associated with the highest incidence of OASIS in the selected articles (19.4%). OASIS in all women had an overall incidence of 3.8%. The incidence of OASIS in all women by geographical region was the highest (6.5%) in North America. CONCLUSIONS: There are various factors that impact on the incidence of OASIS and the combination of some of these, such as the use of forceps in primiparas, resulted in the highest incidence of OASIS. The lack of international consensus is limiting the improvements that can be done to reduce OASIS rates and improve best clinical practice.

Is There Still a Place for Forceps Delivery in Modern Obstetrics?

BACKGROUND: Nowadays, we are witnessing a decrease of vaginal instrumental deliveries and continuous increase of caesarean section rate. However, proper identification of possibility of execution, indications for instrumental delivery and their skilful use may improve the broadly understood maternal and neonatal outcomes. The aim of this study is to present prevalence, risk factors, indications and outcomes of forceps deliveries among the patients at Department of Perinatology, Lodz. MATERIAL AND METHODS: A retrospective study was conducted at the Department of Perinatology, Medical University of Lodz. The study included forceps deliveries carried out between January 2019 and December 2022. Total number of 147 cases were analysed in terms of indications for forceps delivery and maternal and neonatal outcomes such as vaginal - or cervical - laceration, postpartum haemorrhage, perineal tear, newborn injuries, Apgar score, umbilical cord blood gas analysis, NICU admission and cranial ultrasound scans. RESULTS: The prevalence of forceps delivery was 2.2%. The most common indication for forceps delivery was foetal distress (81.6%). Among mothers, the most frequent complication was vaginal laceration (40.1%). Third-and fourth-degree perineal tears were not noted. Regarding neonatal outcomes, Apgar score ≥ 8 after 1st and 5th minute of life received accordingly 91.2% and 98% of newborns. Only 8.8% experienced severe birth injuries (subperiosteal haematoma, clavicle fracture). CONCLUSIONS: Although foetal distress is the most common indication for forceps delivery, the vast majority of newborns were born in good condition and did not require admission to NICU. Taking into consideration high efficacy and low risk of neonatal and maternal complications, forceps should remain in modern obstetrics.

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.

A new approach to assessing the obstetrician's posture and movement during an instrumental forceps delivery.

INTRODUCTION: The number of deliveries by forceps decreases significantly in favour of the vacuum. Now, when the use of forceps is necessary, physicians less experimented with this procedure are likely to induce serious and preventable perineal or foetal injuries. Training therefore becomes essential. However, there are no clear recommendations on the technique to perform a delivery by forceps, namely the body posture and gesture to adopt. Our goal is then to provide a protocol that can help to determine if there is an optimal technique to perform a delivery by forceps. METHOD: We will include voluntary participants whose level of experience and type of practice differ. We will propose to record their postures and gestures using an optoelectronic motion analysis system during a forceps delivery simulated on a mannequin. We will also measure the traction force produced by the subject on the forceps using force platforms and technical markers placed on the forceps. We will then perform a principal component analysis to look for similar motion patterns. EXPECTED RESULTS: We plan to analyse about fifty participants (25 seniors and 25 juniors). Our hypothesis is that the realism of the simulation will be deemed satisfactory by the participants, that the experimental conditions will not modify their gestures, and that the degree of experience will result in different techniques. CONCLUSION: A better knowledge on the posture and gesture to adopt to realise a forceps delivery should improve the safety of women and new-borns. The results of this study could also be a valuable contribution for the training of obstetricians.

A prospective study on neonatal ophthalmic injuries associated with forceps delivery.

BACKGROUND: Assisted delivery by forceps is needed to expedite vaginal delivery in certain maternal and fetal conditions. The aim of this study was to evaluate the incidence and the extent of ophthalmological injuries in neonates after forceps delivery. METHODS: Women with cephalic fetuses delivered vaginally by forceps from July 2020 to June 2022 were recruited prospectively. Ophthalmologists would be consulted when there were signs of external ophthalmic injuries, such as periorbital forceps marks or facial bruising. Demographic data, pregnancy characteristics, delivery details, and perinatal outcomes were evaluated to identify any associated risk factors for neonatal ophthalmological injuries. RESULTS: A total of 77 forceps deliveries were performed in the study period, in which 20 cases (26%) required ophthalmological consultations. There were more right or left occipital fetal head positions in the group requiring ophthalmological assessment than those that did not require assessment (35% vs 12.3% [P = 0.023]). The degree of moulding of the fetal head was more marked in the former group (65% vs 28% [P = 0.001]). The overall incidence of detectable ophthalmological lesions was 16.9% (13/77). All ophthalmic injuries were mild, and most resolved with conservative management. CONCLUSIONS: In our study cohort, external ophthalmic injuries were common after forceps delivery. We recommended ophthalmological consultation in newborns delivered by forceps with evidence of compressive trauma to rule out serious ophthalmological trauma.

Parto vaginal operatório / Operative vaginal delivery

PONTOS-CHAVE Quando utilizados na técnica correta, fórcipes e vácuo-extratores apresentam baixos índices de complicações. Para o feto com sinais de hipóxia no período expulsivo, o parto vaginal operatório tem potencial para reduzir a exposição aos fatores intraparto que promovem a encefalopatia hipóxico-isquêmica. Fórcipes médios e/ou rotacionais são opções apropriadas em circunstâncias selecionadas e exigem habilidade e experiência. Os fórcipes são mais resolutivos do que os vácuo-extratores para o parto vaginal operatório, porém são mais associados a lacerações perineais graves. Céfalo-hematoma é mais provável de ocorrer com o aumento na duração da vácuo-extração. Os vácuo-extratores de campânulas flexíveis apresentam taxas maiores de falha, porém apresentam menores incidências de trauma no couro cabeludo do neonato. (AU)

Consent Practices for Assisted Vaginal Births (AVB) at Two Tertiary Care Hospitals: A Retrospective Review of Physician Documentation.

OBJECTIVE: To determine whether assisted vaginal birth (AVB) consent documentation, a surrogate for in vivo consent, aligns with Canadian practice guidelines at 2 Canadian tertiary-level obstetric centres. METHODS: This was a retrospective review of AVBs (vacuum and forceps) from July 2019 to December 2019 at 2 tertiary-level hospitals with template-based (Site 1) or dictation-based (Site 2) documentation. We extracted, from obstetric and neonatal charts, AVB type, physician and documenter types (resident/fellow/family doctor/generalist obstetrics and gynecology [OBGYN]/maternal-fetal medicine), and consent elements (present/absent) based on a predetermined checklist. Data were summarized and comparisons were made using chi-square test, Fisher exact test, and logistic regression, where appropriate. RESULTS: We identified 551 AVBs (156 forceps, 395 vacuum) with most documentation completed by generalist OBGYNs or residents (333/551, 60.5%). Most vacuum-assisted deliveries documented no specific maternal (366/395, 92.7%) or neonatal (364/395, 92.2%) risks, and 107/156 (68.6%) and 106/156 (67.9%) forceps-assisted deliveries lacked specific documentation of maternal and neonatal risk, respectively. At Site 2, postpartum hemorrhage risk at vacuum-assisted deliveries was more commonly documented (6/90 [6.7%] vs. 2/395 [0.7%], P = 0.002) as was at least 1 neonatal risk and risk of obstetrical anal sphincter injury at forceps-assisted deliveries (50/133 [37.6%] vs. 0/23 [0%], P < 0.001) and (43/133 [32.3%] vs. 0/23 [0%], P = 0.001), respectively. CONCLUSIONS: Opportunity to improve AVB consent documentation exists, warranting quality improvement initiatives.

Clinical and Physician Factors Associated With Failed Operative Vaginal Delivery.

OBJECTIVE: To examine clinical and physician factors associated with failed operative vaginal delivery among individuals with nulliparous, term, singleton, vertex (NTSV) births. METHODS: This was a retrospective cohort study of individuals with NTSV live births with an attempted operative vaginal delivery by a physician between 2016 and 2020 in California. The primary outcome was cesarean birth after failed operative vaginal delivery, identified using linked diagnosis codes, birth certificates, and physician licensing board data stratified by device type (vacuum or forceps). Clinical and physician-level exposures were selected a priori, defined using validated indices, and compared between successful and failed operative vaginal delivery attempts. Physician experience with operative vaginal delivery was estimated by calculating the number of operative vaginal delivery attempts made per physician during the study period. Multivariable mixed effects Poisson regression models with robust standard errors were used to estimate risk ratios of failed operative vaginal delivery for each exposure, adjusted for potential confounders. RESULTS: Of 47,973 eligible operative vaginal delivery attempts, 93.2% used vacuum and 6.8% used forceps. Of all operative vaginal delivery attempts, 1,820 (3.8%) failed; the success rate was 97.3% for vacuum attempts and 82.4% for forceps attempts. Failed operative vaginal deliveries were more likely with older patient age, higher body mass index, obstructed labor, and neonatal birth weight more than 4,000 g. Between 2016 and 2020, physicians who attempted more operative vaginal deliveries were less likely to fail. When vacuum attempts were successful, physicians who conducted them had a median of 45 vacuum attempts during the study period, compared with 27 attempts when vacuum attempts were unsuccessful (adjusted risk ratio [aRR] 0.95, 95% CI 0.93-0.96). When forceps attempts were successful, physicians who conducted them had a median of 19 forceps attempts, compared with 11 attempts when forceps attempts were unsuccessful (aRR 0.76, 95% CI 0.64-0.91). CONCLUSION: In this large, contemporary cohort with NTSV births, several clinical factors were associated with operative vaginal delivery failure. Physician experience was associated with operative vaginal delivery success, more notably for forceps attempts. These results may provide guidance for physician training in maintenance of operative vaginal delivery skills.

Corneal higher-order aberrations in corneal endothelial decompensation secondary to obstetric forceps injury.

Forceps corneal injuries during infant delivery cause Descemet membrane (DM) breaks, that cause corneal astigmatism and corneal endothelial decompensation. The aim of this study is to characterise corneal higher-order aberrations (HOAs) and corneal topographic patterns in corneal endothelial decompensation due to obstetric forceps injury. This retrospective study included 23 eyes of 21 patients (54.0 ± 9.0 years old) with forceps corneal injury, and 18 healthy controls. HOAs and coma aberrations were significantly larger in forceps injury (1.05 [0.76-1.98] µm, and 0.83 [0.58-1.69], respectively) than in healthy controls (0.10 [0.08-0.11], and 0.06 [0.05-0.07], respectively, both P < 0.0001). Patient visual acuity was positively correlated with coma aberration (rs = 0.482, P = 0.023). The most common topographic patterns were those of protrusion and regular astigmatism (both, six eyes, 26.1%), followed by asymmetric (five eyes, 21.7%), and flattening (four eyes, 17.4%). These results indicate that increased corneal HOAs are associated with decreased visual acuity in corneal endothelial decompensation with DM breaks and corneal topography exhibits various patterns in forceps injury.