Operative delivery in the second stage of labor and preterm birth in a subsequent pregnancy: a systematic review and meta-analysis.

OBJECTIVE: This study aimed to quantify the association between mode of operative delivery in the second stage of labor (cesarean delivery vs operative vaginal delivery) and spontaneous preterm birth in a subsequent pregnancy. DATA SOURCES: MEDLINE, Embase, EmCare, CINAHL, the Cochrane Library, Web of Science: Core Collection, and Scopus were searched from database inception to April 1, 2023. STUDY ELIGIBILITY CRITERIA: All retrospective cohort studies with participants who had a second-stage cesarean delivery (defined as intrapartum cesarean delivery at full cervical dilation) or operative vaginal delivery (including forceps- and/or vacuum-assisted delivery) and that reported the rate of preterm birth (either spontaneous or not specified) in subsequent pregnancy were included. METHODS: Both a descriptive analysis and a meta-analysis were performed. A meta-analysis was performed for dichotomous data using the Mantel-Haenszel random-effects model and used the odds ratio as an effect measure with 95% confidence intervals. The risk of bias was assessed using Cochrane's 2022 Risk Of Bias In Non-randomized Studies of Exposure tool. RESULTS: After screening 2671 articles from 7 databases, a total of 18 retrospective cohort studies encompassing 605,138 patients were included. The pooled rates of spontaneous preterm birth in a subsequent pregnancy were 6.9% (12 studies) after second-stage cesarean delivery and 2.6% (8 studies) after operative vaginal delivery. A total of 7 studies encompassing 75,460 patients compared the primary outcome of spontaneous preterm birth after second-stage cesarean delivery vs operative vaginal delivery in an index pregnancy with an odds ratio of 2.01 (95% confidence interval, 1.57-2.58) in favor of operative vaginal delivery. However, most studies did not include important confounding factors, did not address exposure misclassification because of failed operative vaginal delivery, and considered operative vaginal delivery as a homogeneous category with no distinction between forceps- and vacuum-assisted deliveries. CONCLUSION: Although a synthesis of the existing literature suggests that the risk of spontaneous preterm birth is higher in those with a previous second-stage cesarean delivery than in those with operative vaginal delivery, the risk of bias in these studies is very high. Findings should be interpreted with caution.

Prediction of persistent occiput posterior position by sonographic assessment of fetal head attitude at start of second stage of labor: prospective study.

OBJECTIVES: To evaluate the relationship between the attitude of the fetal head quantified by means of the chin-to-chest angle (CCA) in fetuses in occiput posterior (OP) position at the beginning of the second stage of labor, and persistent OP position at birth. METHODS: This was a single-center, prospective observational study conducted at the University Hospital of Parma, Parma, Italy. We included singleton pregnancies at term with fetuses in the OP position at the beginning of the second stage of labor. The fetal head position, station by means of angle of progression and head-to-perineum distance, and attitude by means of CCA were assessed using transabdominal or transperineal ultrasound. The primary outcome was persistent OP position at birth. RESULTS: Between January and July 2022, 76 women were included in the study. There were 48 (63.2%) spontaneous rotations of the fetal head and spontaneous vaginal delivery occurred in all. Among the 28 (36.8%) fetuses that did not rotate spontaneously into an occiput anterior position, eight (28.6%) had a spontaneous vaginal delivery, while operative vaginal delivery and Cesarean delivery was performed in 11 (39.3%) and nine (32.1%) cases, respectively. Multivariable logistic regression analysis showed that the CCA (adjusted odds ratio (aOR), 2.15 (95% CI, 1.22-3.78); P = 0.008) and nulliparity (aOR, 0.20 (95% CI, 0.06-0.76); P = 0.02) were associated independently with persistent OP position at birth. Moreover, the CCA showed an area under the receiver-operating-characteristics curve of 0.69 (95% CI, 0.56-0.82); P = 0.005) for the prediction of persistent OP position. The optimal cut-off value of the CCA was 36.5°, and was associated with a sensitivity of 0.82 (95% CI, 0.63-0.94), specificity of 0.50 (95% CI, 0.35-0.65), positive predictive value of 0.49 (95% CI, 0.34-0.64), negative predictive value of 0.83 (95% CI, 0.64-0.94), positive likelihood ratio of 1.64 (95% CI, 1.18-2.29) and negative likelihood ratio of 0.36 (95% CI, 0.15-0.83). CONCLUSIONS: Our data show that, within a population of women with fetal OP position at the beginning of the second stage of labor, the sonographic fetal head attitude measured by means of the CCA might help in the identification of fetuses at risk of persistent OP position. Such findings can be useful for patient counseling when OP position is diagnosed at full cervical dilatation. Further studies should investigate if the CCA might select patients who may benefit from manual rotation of the fetal head. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Risk of cervical laceration in forceps vs vacuum delivery: A systematic review and meta-analysis.

INTRODUCTION: Cervical laceration is an obstetric injury associated with severe postpartum hemorrhage and subsequent spontaneous preterm birth. While operative vaginal delivery is a known risk factor for cervical laceration, it is unclear whether forceps and vacuum deliveries incur the same risk. The aim of this systematic review was to compare the risk of cervical laceration between operative instruments (forceps vs vacuum). MATERIAL AND METHODS: Medline, Embase, Global Health, CENTRAL, Emcare, and Web of Science were searched from inception until August 2024 with terms related to operative vaginal delivery and cervical laceration. Studies comparing the risk of cervical laceration in individuals undergoing forceps or vacuum delivery were included. Two authors conducted screening, data extraction, and quality assessment of all studies. Random-effects models were used to pool risk ratios across studies and certainty of evidence was assessed using Cochrane methods and the GRADE approach. PROSPERO Registration Number CRD42023421890. RESULTS: Thirteen studies were eligible for inclusion, 3 randomized controlled trials (RCTs) and 10 observational studies. The overall rate of cervical laceration was 0.35% (990/284218 births) where 1.04% of forceps deliveries (456/43817) were complicated by cervical laceration compared to 0.22% of vacuum deliveries (534/240401). The risk of cervical laceration was 2-5 fold greater in forceps deliveries than in vacuum deliveries: pooled unadjusted risk ratio [RR] 4.83, 95% confidence interval [CI] 1.56-14.98 among RCTs and pooled unadjusted RR 1.89, 95% CI 1.59-2.24 among observational studies. The overall quality of evidence was low to moderate mainly due to the lack of attention to confounding in the included literature. The GRADE assessment indicated that the certainty of evidence was very low for observational studies and moderate for RCTs. CONCLUSIONS: Low certainty of evidence indicates that forceps deliveries may be associated with an increased risk of cervical laceration compared to vacuum deliveries.

Obstetric claims in Finland 2012-2022-A nationwide patient insurance registry study.

INTRODUCTION: Maternal and infant mortality rates in Finland are among the lowest in the world, yet preventable obstetric injuries occur every year. The aim of this study was to describe obstetric claims, their compensation rates, and temporal trends of claims reported to the Patient Insurance center. MATERIAL AND METHODS: A nationwide, register-based study was conducted. Data consisted of obstetric claims reported to the Patient Insurance Center between 2012 and 2022. Data analyzed included the year of injury, compensation criteria, maternal age, birth hospital, delivery method, reported causes of injury, and maternal or neonatal injury. The data were analyzed with descriptive statistics and logistic regression models. RESULTS: A total of n = 849 obstetric claims were filed during the study period, of which n = 224 (26.4%) received compensation. The rate of claims was 0.15%, and the rate of compensation was 0.04% in relation to the total volume of births during the period. Substandard care was the most common (97.3%) criterion for compensation. There was a curvilinear increase in the claims rate and a linear increase in compensation rates from 2013 to 2019. More claims were filed and compensated for cesarean and vacuum-assisted deliveries than for unassisted vaginal deliveries. Delayed delivery (18.7%) and surgical technique failure (10.9%) were the most reported causes of injuries. Retained surgical bodies were the induced cause of injury with the highest rate of compensated claims (86.7%). The most common maternal injury was infection (17.9%) and pain (11.7%). Among neonatal injuries, severe (19.2%) and mild asphyxia (16.6%) were the most frequent. Burn injuries (93.3%) and fetal or neonatal death (60.5%) had the highest rate of compensated claims. CONCLUSIONS: The study provided new information on substandard care and injuries in obstetric care in Finland. An increasing trend in claims and compensation rates was found. Identifying contributors to substandard care that lead to fetal asphyxia is important for improving obstetric safety. Further analysis of the association of claims and compensation rates with operative deliveries is needed to determine their causality. Frequent review of obstetric claims would be useful in providing more recent data on substandard care and preventable injuries.

Uterine contractile activity and neonatal outcome - A blind analysis of a randomized controlled trial cohort.

INTRODUCTION: Sufficient contractions are necessary for a successful delivery but each contraction temporarily constricts the oxygenated blood flow to the fetus. Individual fetal or placental characteristics determine how the fetus can withstand this temporary low oxygen saturation. However, only a few studies have examined the impact of uterine activity on neonatal outcome and even less attention has been paid to parturients' individual characteristics. Our objective was therefore to find out whether fetuses compromised by maternal or intrapartum risk factors are more vulnerable to excessive uterine activity. MATERIAL AND METHODS: Uterine contractile activity was assessed by intrauterine pressure catheters. Women (n = 625) with term singleton pregnancies and fetus in cephalic presentation were included in this secondary, blind analysis of a randomized controlled trial cohort. Intrauterine pressure as Montevideo units (MVU), contraction frequency/10 min and uterine baseline tone were calculated for 4 h prior to birth or the decision to perform cesarean section. Uterine activity in relation to umbilical artery pH linearly or ≤7.10 was used as the primary outcome. Need for operative delivery (either cesarean section or vacuum-assisted delivery) due to fetal distress was analyzed as a secondary outcome. In addition, belonging to vulnerable subgroups with, for example, chorioamnionitis, hypertensive or diabetic disorders, maternal smoking or neonatal birthweight <10th percentile were investigated as additional risk factors. RESULTS: A linear decline in umbilical artery pH was seen with increasing intrauterine pressure in all deliveries (p < 0.001). Among parturients with suspected chorioamnionitis, every increasing 10 MVUs increased the likelihood of umbilical artery pH ≤7.10 (odds ratio [OR] 1.17, 95% confidence interval [CI] 1.02-1.34, p = 0.023). The need for operative delivery due to fetal distress was increased among all laboring women by every increasing 10 MVUs (OR 1.05, 95% CI 1.01-1.09, p = 0.015). This association with operative deliveries was further increased among parturients with hypertensive disorders (OR 1.23, 95% CI 1.05-1.43, p = 0.009) and among those with diabetic disorders (OR 1.13, 95% CI 1.04-1.28, p = 0.003). CONCLUSIONS: Increasing intrauterine pressure impairs umbilical artery pH especially among parturients with suspected chorioamnionitis. Fetuses in pregnancies affected by chorioamnionitis, hypertensive or diabetic disorders are more vulnerable to high intrauterine pressure.

First and Second Stage Risk Factors Associated with Perineal Lacerations.

OBJECTIVE: To determine intrapartum factors associated with perineal laceration at delivery. METHODS: This was a planned secondary analysis of a multicenter randomized clinical trial of delayed versus immediate pushing among term nulliparous women in labor with neuraxial analgesia conducted in the United States. Intrapartum characteristics were extracted from the medical charts. The primary outcome was perineal laceration, defined as second degree or above, characterized at delivery in women participating in longer term pelvic floor assessments post-delivery. Multivariable logistic regression was used to refine risk estimates while adjusting for randomization group, birth weight, and maternal age. RESULTS: Among the 941 women participating in the pelvic floor follow-up, 40.6% experienced a perineal laceration. No first stage labor characteristics were associated with perineal laceration, including type of labor or length of first stage. Receiving an amnioinfusion appeared protective of perineal laceration (adjusted odds ratio, 0.48; 95% confidence interval 0.26-0.91; P = 0.01). Second stage labor characteristics associated with injury were length of stage (2.01 h vs. 1.50 h; adjusted odds ratio, 1.36; 95% confidence interval 1.18-1.57; P < 0.01) and a prolonged second stage (adjusted odds ratio, 1.64; 95% confidence interval 1.06-2.56; P < 0.01). Operative vaginal delivery was strongly associated with perineal laceration (adjusted odds ratio, 3.57; 95% confidence interval 1.85-6.90; P < 0.01). CONCLUSION: Operative vaginal delivery is a modifiable risk factor associated with an increased risk of perineal laceration. Amnioinfusion appeared protective against injury, which could reflect a spurious finding, but may also represent true risk reduction similar to the mechanism of warm perineal compress.

Uterine artery Doppler in early labor and perinatal outcome in low-risk term pregnancy: prospective multicenter study.

OBJECTIVE: The prediction of adverse perinatal outcomes in low-risk pregnancies is poor, mainly owing to the lack of reliable biomarkers. Uterine artery (UtA) Doppler is closely associated with placental function and may facilitate the peripartum detection of subclinical placental insufficiency. The objective of this study was to evaluate the association of mean UtA pulsatility index (PI) measured in early labor with obstetric intervention for suspected intrapartum fetal compromise and adverse perinatal outcome in uncomplicated singleton term pregnancies. METHODS: This was a prospective multicenter observational study conducted across four tertiary maternity units. Low-risk term pregnancies with spontaneous onset of labor were included. The mean UtA-PI was recorded between uterine contractions in women admitted for early labor and converted into multiples of the median (MoM). The primary outcome of the study was the occurrence of obstetric intervention, i.e. Cesarean section or instrumental delivery, for suspected intrapartum fetal compromise. Secondary outcomes were the occurrence of adverse perinatal outcomes, including 5-min Apgar score < 7, low cord arterial pH, raised cord arterial base excess, admission to the neonatal intensive care unit (NICU) and postnatal diagnosis of small-for-gestational-age fetus. Composite adverse perinatal outcome was defined as the occurrence of at least one of the following: acidemia in the umbilical artery, defined as pH < 7.10 and/or base excess > 12 mmol/L, 5-min Apgar score < 7 or admission to the NICU. RESULTS: Overall, 804 women were included, of whom 40 (5.0%) had abnormal mean UtA-PI MoM. Women who had an obstetric intervention for suspected intrapartum fetal compromise were more frequently nulliparous (72.2% vs 53.6%; P = 0.008), had a higher frequency of increased mean UtA-PI MoM (13.0% vs 4.4%; P = 0.005) and had a longer duration of labor (456 ± 221 vs 371 ± 192 min; P = 0.01). On logistic regression analysis, only increased mean UtA-PI MoM (adjusted odds ratio (aOR), 3.48 (95% CI, 1.43-8.47); P = 0.006) and parity (aOR, 0.45 (95% CI, 0.24-0.86); P = 0.015) were independently associated with obstetric intervention for suspected intrapartum fetal compromise. Increased mean UtA-PI MoM was associated with a sensitivity of 0.13 (95% CI, 0.05-0.25), specificity of 0.96 (95% CI, 0.94-0.97), positive predictive value of 0.18 (95% CI, 0.07-0.33), negative predictive value of 0.94 (95% CI, 0.92-0.95), positive likelihood ratio of 2.95 (95% CI, 1.37-6.35) and negative likelihood ratio of 0.91 (95% CI, 0.82-1.01) for obstetric intervention for suspected intrapartum fetal compromise. Pregnancies with increased mean UtA-PI MoM also showed a higher incidence of birth weight < 10th percentile (20.0% vs 6.7%; P = 0.002), NICU admission (7.5% vs 1.2%; P = 0.001) and composite adverse perinatal outcome (15.0% vs 5.1%; P = 0.008). CONCLUSION: Our study, conducted in a cohort of low-risk term pregnancies enrolled in early spontaneous labor, showed an independent association between increased mean UtA-PI and obstetric intervention for suspected intrapartum fetal compromise, albeit with moderate capacity to rule in, and poor capacity to rule out, this condition. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Neonatal outcomes associated with time from a high fetal blood lactate concentration to operative delivery.

INTRODUCTION: Adjunctive technologies to cardiotocography intend to increase the specificity of the diagnosis of fetal hypoxia. If correctly diagnosed, time to delivery could affect neonatal outcome. In the present study, we aimed to investigate the effect of time from when fetal distress is indicated by a high fetal blood sample (FBS) lactate concentration to operative delivery on the risk of adverse neonatal outcomes. MATERIAL AND METHODS: We conducted a prospective observational study. Deliveries with a singleton fetus in cephalic presentation at 36+0 weeks of gestation or later were included. Adverse neonatal outcomes, related to decision-to-delivery interval (DDI), were investigated in operative deliveries indicated by an FBS lactate concentration of at least 4.8 mmol/L. We applied logistic regression to estimate crude and adjusted odds ratios (aOR) of various adverse neonatal outcomes, with associated 95% confidence intervals (CI), for a DDI exceeding 20 minutes, compared with a DDI of 20 minutes or less. CLINICALTRIALS: gov Identifier: NCT04779294. RESULTS: The main analysis included 228 women with an operative delivery indicated by an FBS lactate concentration of 4.8 mmol/L or greater. The risk of all adverse neonatal outcomes was significantly increased for both DDI groups compared with the reference group (deliveries with an FBS lactate below 4.2 mmol/L within 60 minutes before delivery). In operative deliveries indicated by an FBS lactate concentration of 4.8 mmol/L or more, there was a significantly increased risk of a 5-minute Apgar score less than 7 if the DDI exceeded 20 minutes, compared with a DDI of 20 minutes or less (aOR 8.1, 95% CI 1.1-60.9). We found no statistically significant effect on other short-term outcomes for deliveries with DDI longer than 20 minutes, compared with those with DDI of 20 minutes or less (pH ≤7.10: aOR 2.0, 95% CI 0.5-8.4; transfer to the neonatal intensive care unit: aOR 1.1, 95% CI 0.4-3.5). CONCLUSIONS: After a high FBS lactate measurement, the increased risk of adverse neonatal outcome is further augmented if the DDI exceeds 20 minutes. These findings give support to current Norwegian guidelines for intervention in cases of fetal distress.

Factors influencing the effect of external cephalic version: a retrospective nationwide cohort analysis.

OBJECTIVE: This study aims to assess the factors associated with the success and failure rate of the external cephalic version (ECV) in breech fetuses. Secondary outcomes were fetal presentation in labor and mode of delivery. METHODS: This cross-sectional study examined the live birth certificates from 2003 through 2020 from US states and territories that implemented the 2003 revision. A total of 149,671 singleton pregnancies with information about ECV success or failure were included. The outcome was ECV success/failure, while the exposures were possible factors associated with the outcome. RESULTS: The successful ECV procedures were 96,137 (64.23%). Among the successful ECV procedures, the prevalence of spontaneous vaginal delivery was 71.63%. Among the failed ECV procedures, 24.74% had a cephalic presentation at delivery, but 63.11% of these pregnancies were delivered by cesarean section. Nulliparity, female sex, low fetal weight centile, high pre-pregnancy BMI, high BMI at delivery, and high maternal weight gain during pregnancy were associated with an increased ECV failure (p < 0.001). African American, American Indian and Alaska Native race categories were significant protective factors against ECV failure (p < 0.001). Maternal age had a U-shape risk profile, whereas younger maternal age (< 25 years) and old maternal age (> 40 years) were significant protective factors against ECV failure (p < 0.001). CONCLUSIONS: A high prevalence of successful ECV procedures and subsequent spontaneous vaginal delivery were found. The present results found nulliparity, maternal race, maternal age, female fetal sex, low fetal weight, and maternal anthropometric features correlated to ECV results. These findings can potentially improve the knowledge about the factors involved in ECV, allowing more informed counseling to the women undergoing this procedure.

Manual rotation of occiput posterior or transverse positions: a systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE: The primary objective of this systematic review was to assess the association between spontaneous vaginal delivery and manual rotation during labor for occiput posterior or transverse positions. Our secondary objective was to assess maternal and neonatal outcomes. DATA SOURCES: An electronic search of PubMed, EMBASE, ClinicalTrials.gov, and the Cochrane Register of Controlled Trials covered the period from January 2000 to September 2021, without language restrictions. STUDY ELIGIBILITY CRITERIA: The eligibility criteria included all randomized trials with singleton pregnancies at ≥37 weeks of gestation comparing the manual rotation groups with the control groups. The primary outcome was the rate of spontaneous vaginal delivery. Additional secondary outcomes were rate of occiput posterior position at delivery, operative vaginal delivery, cesarean delivery, postpartum hemorrhage, obstetrical anal sphincter injury, prolonged second stage of labor, shoulder dystocia, neonatal acidosis, and phototherapy. Subgroup analyses were performed according to types of position (occiput posterior or occiput transverse), techniques used (whole-hand or digital rotation), and parity (nulliparous or parous). METHODS: The quality of each study was evaluated with the revised Cochrane risk-of-bias tool for randomized trials, known as RoB 2. The meta-analysis used random-effects models depending on their heterogeneity, and risks ratios were calculated for dichotomous outcomes. RESULTS: Here, 7 of 384 studies met the inclusion criteria and were selected. They included 1402 women: 704 in the manual rotation groups and 698 in the control groups. Manual rotation was associated with a higher rate of spontaneous vaginal delivery: 64.9% vs 59.5% (risk ratio, 1.09; 95% confidence interval, 1.03-1.16; P=.005; 95% prediction interval, 0.90-1.32). This association was no longer significant after stratification by parity or technique used. Manual rotation was associated with spontaneous vaginal delivery only for the occiput posterior position (risk ratio, 1.08; 95% confidence interval, 1.01-1.15). Furthermore, it was associated with a reduction in occiput posterior or transverse positions at delivery (risk ratio, 0.64; 95% confidence interval, 0.48-0.87) and episiotomies (risk ratio, 0.84; 95% confidence interval, 0.71-0.98). The groups did not differ significantly for cesarean deliveries, operative vaginal deliveries, or neonatal outcomes. CONCLUSION: Manual rotation increased the rate of spontaneous vaginal delivery.

Association between first and second stage of labour duration and mode of delivery: A population-based cohort study.

BACKGROUND: Active first stage of labour duration can widely vary between women. However, the nature of the relationship between the active first stage and second stage of labour duration is sparsely studied. OBJECTIVES: To determine whether active first stage of labour duration (i) influences second stage of labour duration; and (ii) is associated with mode of delivery. METHODS: A population-based cohort study of 13,379 women primiparous women, with spontaneous start in Stockholm-Gotland Region, Sweden, between 2008 and 2014. Duration of the active first stage of labour was examined in relation to second-stage duration using univariate and multivariable quantile regressions, with the first quartile (first stage duration) as the reference. Nonlinearity of associations was tested by restricted cubic splines. Association between active first-stage duration with mode of delivery was estimated using a multinomial logistic regression based on adjusted odds ratios. RESULTS: Longer active first stage of labour duration was linearly associated with longer second stage of labour duration until approximately 12 h of active first stage of labour duration. After 12 h, a non-linear trend is seen, demonstrated by a plateau in the second-stage duration. In addition, longer active first stage of labour duration was associated with increased occurrence of operative vaginal delivery (adjusted odds ratio 3.36, 95% confidence interval [CI] 2.89, 3.89) and caesarean delivery (adjusted odds ratio 4.75, 95% CI 3.85, 5.80). CONCLUSIONS: Among primiparous women with spontaneous onset of labour, longer active first stage of labour duration was associated with both longer second stage of labour duration and higher odds of operative delivery. This study contributes with findings, which may inform future discussions regarding how to properly account for second-stage duration, with applications in obstetric and perinatal epidemiology.

Angle of progression measured using transperineal ultrasound for prediction of uncomplicated operative vaginal delivery: systematic review and meta-analysis.

OBJECTIVE: To determine whether intrapartum transperineal ultrasound measurement of the angle of progression (AoP) during the second stage of labor can predict uncomplicated operative vaginal delivery (OVD) using vacuum or forceps extraction. METHODS: A systematic search in PubMed, EMBASE, Scopus, Web of Science and Google Scholar was performed from inception to February 2021. Studies assessing the predictive accuracy of AoP, measured using intrapartum transperineal ultrasound, for uncomplicated OVD, defined as successful vaginal delivery within three pulls using forceps or no more than two detachments of the vacuum extractor cup, were included. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. Summary receiver-operating-characteristics (ROC) curves, pooled sensitivity and specificity, area under the ROC curve (AUC) and summary likelihood ratios (LRs) were calculated. RESULTS: Seven studies reporting on a total of 782 patients undergoing OVD were included in this systematic review and meta-analysis. Second-stage AoP measured during maternal rest had a pooled sensitivity of 80% (95% CI, 59-92%) and specificity of 89% (95% CI, 76-95%), with a LR+ of 7.3 (95% CI, 3.1-15.8) for uncomplicated OVD. AoP measured during active pushing had a sensitivity of 91% (95% CI, 85-94%) and specificity of 83% (95% CI, 69-92%), with a LR+ of 5.4 (95% CI, 2.7-10.6) for uncomplicated OVD. The performance of AoP measured at rest was particularly high in nulliparous women, with a sensitivity of 87% (95% CI, 75-94%) and specificity of 90% (95% CI, 82-94%) for uncomplicated OVD. CONCLUSION: AoP may be a reliable predictor for uncomplicated OVD when measured during the second stage of labor, especially in nulliparous women. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Cephalic marks and well-being in newborns after operative vaginal delivery.

OBJECTIVES: To compare the incidence of cephalic marks in newborns exposed to operative vaginal delivery and those who are not. We examined the factors associated with alterations in neonatal well-being and with cephalic mark occurrence. METHODS: Prospective study involving singleton term newborns delivered in a cephalic presentation. Newborns in the operative group were matched with newborns born on the same day without instruments required. A cephalic mark was defined as any mark or edema on the newborn's skin between 12 and 72 hours of life. Neonatal well-being was assessed by analgesic consumption, neonatal discomfort (EDIN score of 1 or more), and prolonged hospitalization (4 days or more). We compared the operative and spontaneous groups and determined the relative risk (RR) for cephalic marks. We investigated the factors associated with alterations in neonatal well-being and factors associated with cephalic mark occurrence in the case of operative delivery using multivariate logistic regression analysis. RESULTS: A total of 135 newborns were included in each group. The incidence of cephalic marks was higher in the operative group (RR = 13.3 [6.0-29.5]). In case of operative delivery, cephalic marks were associated with neonatal discomfort (adjusted odds ratios [aOR] = 8.2 [2.2-30.6]) and analgesic consumption (aOR = 3.0 [1.2-7.1]). The number of cephalic marks was higher in cases with sequential use of vacuum and forceps (aOR = 3.5 [1.1-11.7]) and forceps only deliveries (aOR = 3.0 [1.1-8.1]) relative to vacuum only deliveries. CONCLUSIONS: Operative delivery increases the risk of neonatal cephalic marks, which can negatively affect neonatal well-being.

Sonographic risk assessment for an unplanned operative delivery: a prospective study.

PURPOSE: To assess the value of pre-labor maternal and fetal sonographic variables to predict an unplanned operative delivery. METHODS: In this prospective study, nulliparous women were recruited at 37.0-42.0 weeks of gestation. Sonographic measurements included estimated fetal weight, maternal pubic arch angle, and the angle of progression. We performed a descriptive and comparative analysis between two outcome groups: spontaneous vaginal delivery (SVD) and unplanned operative delivery (UOD) (vacuum-assisted, forceps-assisted and cesarean deliveries). Multivariate logistic regression with ROC analysis was used to create discriminatory models for UOD. RESULTS: Among 234 patients in the study group, 175 had a spontaneous vaginal delivery and 59 an unplanned operative delivery. Maternal height and pubic arch angle (PAA) significantly correlated with UOD. Analysis of Maximum Likelihood Estimates revealed a multivariate model for the prediction of UOD, including the parameters of maternal age, maternal height, sonographic PAA, angle of progression (AOP), and estimated fetal weight, with an area under the curve of 0.7118. CONCLUSION: Sonographic parameters representing maternal pelvic configuration (PAA) and maternal-fetal interface (AOP) improve the prediction ability of pre-labor models for a UOD. These data may aid the obstetrician in the counseling process before delivery.

Risk factors associated with breakdown of perineal laceration repair after vaginal birth.

Underlying infection, estimated blood loss >500 ml and operative delivery are independent risk factors for breakdown of perineal laceration repair after vaginal birth.

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

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

Prophylactic manual rotation of occiput posterior and transverse positions to decrease operative delivery: the PROPOP randomized clinical trial.

BACKGROUND: Persistent occiput posterior and occiput transverse positions are the most common malpositions of the fetal head during labor and are associated with prolonged second stage of labor, cesarean deliveries, instrumental deliveries, severe perineal tears, postpartum hemorrhage, and chorioamnionitis. Manual rotation is one of several strategies described to deal with these malpositions. OBJECTIVE: This study aimed to determine if the trial of prophylactic manual rotation at the early second stage of labor is associated with a decrease in operative deliveries (instrumental and/or cesarean deliveries). STUDY DESIGN: We conducted a multicenter, open-label, randomized controlled trial in 4 French hospitals. Women with singleton term pregnancy and occiput posterior or occiput transverse position confirmed by ultrasound at the early second stage of labor and with epidural analgesia were eligible. Women were randomly assigned (1:1) to either undergo a trial of prophylactic manual rotation of occiput posterior or occiput transverse position (intervention group) or no trial of prophylactic manual rotation (standard group). The primary outcome was operative delivery (instrumental and/or cesarean deliveries). The secondary outcomes were length of the second stage of labor, maternal complications (postpartum hemorrhage, operative complications during cesarean delivery, episiotomy and perineal tears), and neonatal complications (Apgar score of <5 at 10 minutes, arterial umbilical pH of <7.10, neonatal injuries, neonatal intensive care unit admission). The main analysis was focused on intention-to-treat analysis. RESULTS: From December 2015 to December 2019, a total of 257 women (mean age, 30.4 years; mean gestational age, 40.1 weeks) were randomized: 126 were assigned to the intervention group and 131 were assigned to the standard group. Operative delivery was significantly less frequent in the intervention group compared with the standard group (29.4% [37 of 126] vs 41.2% [54 of 131]; P=.047; differential [intervention-standard] [95% confidence interval] = -11.8 [-15.7 to -7.9]; unadjusted odds ratio [95% confidence interval] = 0.593 [0.353-0.995]). Women in the intervention group were more likely to have a significantly shorter second stage of labor. CONCLUSION: Trial of prophylactic manual rotation of occiput posterior or occiput transverse positions during the early second stage of labor was statistically associated with a reduced risk of operative delivery. This maneuver could be a safe strategy to prevention operative delivery.

The association between vacuum-assisted vaginal delivery and anal sphincter injury.

INTRODUCTION: Vacuum-assisted vaginal delivery (VAVD) is considered a major risk factor for obstetric anal sphincter injuries (OASIS). However, it is difficult to estimate its true contribution to the occurrence of OASIS, as its performance may be confounded by other determinants. Therefore, we aimed to evaluate the association of VAVD with OASIS among primiparous women compared to SVD. METHODS: A retrospective cohort study including all primiparous women who vaginally delivered a cephalic singleton gestation during the years 2011 to 2020. As VAVDs were not performed before 34 gestational weeks, we capped the cohort at this gestational age. Women were allocated into two groups: VAVDs and spontaneous vaginal deliveries (SVD). We compared women with OASIS to those without and performed a multivariate analysis including factors that were found significant in the univariate analysis. We further divided the whole cohort into different subcategories. The primary outcome was the rate of OASIS in VAVD compared to SVD. RESULTS: Overall, 23,272 primiparous vaginal deliveries were available for evaluation. Of these, 3595 delivered by VAVD and 19,677 delivered spontaneously. OASIS occurred in 421 (1.8%) of the deliveries. OASIS were more common in VAVDs than in SVDs [83 (2.3%) vs. 338 (1.7%), respectively, OR (95% CI) 1.35 (1.06-1.72), p = 0.01]. After multivariate regression analysis, OASIS were not found to be independently associated with the mode of delivery [aOR 1.21 (95% CI) 0.88-1.68, P = 0.23]. In a categorical analysis of OASIS rates by risk factors and mode of delivery, VAVD was not associated with an increase in OASIS among women giving birth to neonates weighing > 3500 g compared to SVD [OR (95% CI) 1.02 (0.65-1.62), P = 0.90]. CONCLUSION: Among primiparous women VAVD did not increase the risk of OASIS compared to SVD.

Composite non-clinical interventions for a safe cesarean section rate reduction: results of a pre-post interventional study.

OBJECTIVE: To evaluate the impact on cesarean section (CS) rate with of a program of multiple non-clinical interventions targeted at health-care professional within a hospital maternity ward. MATERIALS AND METHODS: Retrospective quasi-experimental pre-post intervention study with an historical control group conducted in a second-level teaching hospital. All women who gave birth in the period 2014 to 2018 were included. A series of multiple non-clinical interventions including a dedicated team of obstetricians for delivery room and antenatal counseling, monthly internal audits and physician education by local opinion leader were prospectively introduced from September 2016. The primary outcome of the study was the CS rate. The incidences of operative vaginal delivery, 3rd-/4th-degree perineal tears and further maternal and neonatal complications were considered as secondary outcomes. RESULTS: The CS rate dropped from 33.05 to 26.06% after starting the interventions (p < 0.01); in particular, the cumulative rate of CS performed during labor decreased significantly from 19.46 to 14.11% (p < 0.01). CS reduction was still statistically significant after multivariate correction (OR = 0.66, CI.95 = 0.57-0.76, p < 0.01). Results further showed an increased prevalence of 3rd-degree perineal tears (0.97% versus 2.24%, p < 0.01), present also after correcting for possible confounding factors (OR = 2.36, CI.95 = 1.48-3.76, p < 0.01). No differences were found in the rate of vaginal-operative births and further maternal complications, while the composite neonatal outcome was found to be improved (OR = 0.73, CI.95 = 0.57-0.93, p = 0.010). CONCLUSIONS: The introduction of multiple non-clinical interventions can significantly reduce the CS rate. However, beside an improvement in neonatal composite outcome, a potential increase in high-degree perineal tears should be taken in account.

A core outcome set development for a French national prospective study about the effect of mediolateral episiotomy on obstetric anal sphincter injury during operative vaginal delivery (INSTRUMODA).

BACKGROUND: We aimed at developing a core outcome and variables of interest set to investigate the effects of mediolateral episiotomy on Obstetric Anal Sphincter Injury (OASI) during and after operative delivery in nulliparous women in a large-scale one-year observational French study including 15,000 women (INSTRUMODA). METHODS: A list of outcomes and variables of interest was suggested to obstetricians participating in the INSTRUMODA study using online questionnaires divided into 7 categories: the woman's history and course of pregnancy, course of labor, modalities of operative delivery, episiotomy characteristics, immediate maternal morbidity, one-year maternal morbidity, immediate neonatal morbidity. We used a three-round DELPHI method to reach a consensus. In the first round, outcomes and variables considered as essential by 70% or more of obstetricians were included in the corpus whereas they were excluded when 70% rated them as "not important". In the second round, non-consensual outcomes and variables were reassessed and excluded or definitively included if considered as "not important" or essential by 50% or more of the obstetricians. During the first round, obstetricians were invited to suggest new outcomes and/or variables that were then assessed in the second and third round. We used the same method to develop a core outcome and variables of interest set in a population of women in the community recruited via an association of patients. At the end of the procedure the core outcome and variables of interest sets were merged to provide the final core outcome set for the INSTRUMODA study. RESULTS: Fifty-three obstetricians and 16 women filled out questionnaires. After the 3 rounds of Delphi procedure in each population, 74 outcomes and variables were consensually reported by obstetricians and 92 by women in the community. By mixing these two consensual corpora we reported a final consensual list of 114 variables of interest and outcomes for both obstetricians and women. CONCLUSION: We established a core outcome and variables of interest set among obstetricians and women in the community to investigate the association between mediolateral episiotomy and OASI during operative delivery. TRIAL REGISTRATION: The INSTRUMODA study was registered on https://clinicaltrials.gov on June 25, 2020 ( NCT04446780 ).