Newborn shoulder width: a prospective study of 2222 consecutive measurements.

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To identify factors associated with the development of neonatal injury in the setting of shoulder dystocia. Medical record ICD-9 codes and a computerized perinatal database were reviewed to identify cases of shoulder dystocia from January 1996 to January 2001 in a tertiary care center. For confirmation of the diagnosis and collection of data, both maternal and neonatal charts were then reviewed and neonatal injuries categorized as either neurological (brachial plexus injury) or skeletal (clavicular fracture, humeral fracture). Shoulder dystocia cases were divided into groups based on the presence of neonatal injury at delivery or at discharge (with or without Erb's palsy). The group with neonatal injury was compared for demographic and obstetrical factors to the group without injury (control). chi (2) test, Mann-Whitney test and logistic regression were used as appropriate. During this 5-year period, there were 25,995 deliveries and 206 (0.8%) confirmed cases of shoulder dystocia. Of these cases, 36 (17.5%) had neonatal injury diagnosed at delivery and 25 (12%) remained with significant residual injury at discharge. Of these there were 19 cases of Erb's palsy and six cases of clavicular fracture. No association was found between neonatal injury and maternal age, ethnicity, diabetes, operative vaginal delivery or number of obstetrical maneuvers. However, maternal body mass index >30 kg/m2, a second stage of labor >20 min and a birth weight >4500 g were all associated with an increased risk of neonatal injury at delivery and at discharge, including Erb's palsy. After logistic regression analysis, only a second stage of delivery >20 min remained significantly associated with neonatal injury at discharge. In our population, maternal obesity was associated with an increased risk of neonatal injury after shoulder dystocia. In addition, a short second stage of labor (<20 min) was associated with a lower rate of neonatal injury.

BackgroundMcRoberts’ and suprapubic pressure are often recommended as the initial choices of manoeuvres to manage shoulder dystocia, as they are believed to be less invasive compared to other manoeuvres. However, their success rates range from 23 to 40 %. This study aims to investigate the predictive factors for the success of McRoberts’ manoeuvre with or without suprapubic pressure (M+/−S).MethodsAll cases of shoulder dystocia in a tertiary hospital in South East Asia were recruited from 1995 to 2009. Subjects were analysed according to either ‘success’ or ‘failure’ of M+/−S. Maternal and fetal antenatal and intrapartum factors were compared by univariate and multivariate analysis.ResultsAmong 198 cases of shoulder dystocia, M+/−S as the primary manoeuvre was successful in 25.8 %. The other 74.2 % needed either rotational or posterior arm manoeuvres or combination of manoeuvres. Instrumental delivery was the single most significant factor associated with an increased risk of failed M+/−S on logistic regression (p < 0.001, OR 4.88, 95 % CI 2.05–11.60). The success rate of M+/−S was only 15.0 % if shoulder dystocia occurred after instrumental delivery but was 47.7 % after spontaneous vaginal delivery.ConclusionsWhen shoulder dystocia occurs after instrumental vaginal delivery, the chance of failure of M+/−S is 85 %, which is 4.7 times higher than that after spontaneous vaginal delivery. Hence all operators performing instrumental delivery should be proficient in performing all manoeuvres to relieve shoulder dystocia when M+/−S cannot do so.

Perinatal outcome of fetuses with a birth weight greater than 4500 g: an analysis of 3356 cases

The cost-effectiveness of early induction of labour for suspected large-for-gestational-age foetuses to prevent shoulder dystocia is unknown. A within-trial economic evaluation of induction at 38 + 0 to 38 + 4 weeks' gestation for suspected large-for-gestational-age foetuses. Resource use and costs were measured to 6 months postpartum. We estimated incremental cost per case of shoulder dystocia prevented and incremental cost per maternal quality-adjusted life year (QALY) gained. We collected data for planned caesarean sections in a cohort study. Mean combined woman and infant costs in the induction arm were £89 (95% confidence interval (CI): -£79, £257) higher than the standard care arm, driven by increased neonatal costs. The incremental cost of preventing one case of shoulder dystocia was £11 879 and the incremental cost per maternal QALY gained was £39 518. The probability of early induction being cost-effective was 0.65 at a cost-effectiveness threshold of £20 000 per case of shoulder dystocia prevented, but 0.36 at a cost-effectiveness threshold of £20 000 per maternal QALY gained. The cohort study found the mean cost was £310 (95% CI: £74, £545) higher in the induction arm than in the planned caesarean group. Early induction of labour increased neonatal care costs. It is not a cost-effective approach when effects are restricted to maternal QALYs. Planned caesarean section might be cost-saving when compared to early induction, although we did not assess longer-term effects such as an increased risk of repeat caesarean sections. Assessments of long-term effects on the mother and infant should be incorporated into future studies. ISRCTN18229892.

Objective This study aims to determine if shoulder dystocia is associated with a difference in the fetal abdominal (AC) to head circumference (HC) of 50 mm or more noted on antenatal ultrasound.Study Design A multicenter matched case–control study was performed comparing women who had shoulder dystocia to controls who did not. Women with vaginal births of live born nonanomalous singletons ≥ 36 weeks of gestation with an antenatal ultrasound within 4 weeks of delivery were included. Controls were matched for gestational age, route of delivery, and diabetes status.Results We identified 181 matched pairs. Only 5% of the fetuses had an AC to HC of ≥ 50 mm. The proportion of AC to HC difference of ≥ 50 mm was significantly higher in shoulder dystocia cases (8%) than controls (1%, p = 0.002). With multivariate regression, the three significant factors associated with shoulder dystocia were AC to HC ≥ 50 mm (odds ratio [OR], 7.3; confidence interval [CI], 1.6–33.3; p = 0.010), femur length (OR, 1.1; CI, 1.0–1.2; p = 0.002), and induced labor (OR, 1.8; CI, 1.1–3.1; p = 0.027).Conclusion A prenatal ultrasound finding of a difference in AC to HC of ≥ 50 mm while uncommon is associated with shoulder dystocia.

Most shoulder dystocia (SD) cases do not have associated adverse outcomes. The objective was to assess whether SD relieved with ≥3 maneuvers, compared with fewer, is associated with a higher likelihood of adverse outcomes. The secondary objective was to examine if postpartum hemorrhage is associated with SD managed with ≥3 maneuvers versus fewer.This was a secondary analysis of the assessment of perinatal excellence (APEX) study, an observational cohort of over 115,000 deliveries in 25 U.S. hospitals from 2008 to 2011. We included individuals with singleton, vertex, and nonanomalous fetuses at ≥34 weeks who had SD requiring at least one maneuver. We stratified participants according to if ≥3 maneuvers, versus fewer, were utilized to resolve the SD. The primary outcome was the incidence of a neonatal composite adverse outcome including APGAR <5 at 5 minutes, fetal fractures, intracranial hemorrhage, brachial plexus palsy, facial nerve palsy, hypotension treated, hypoxic-ischemic encephalopathy, or neonatal death. Using modified-Poisson-regression, we calculated adjusted incidence relative risk (aIRR) with 95% confidence intervals (CI).The rate of SD in APEX was 1.9% (2,138/118,422). Of 2,138 cases of SD, 96% met the inclusion criteria. ≥3 maneuvers were utilized in 18.9% (391/2,062) of SD cases. The composite neonatal adverse outcome occurred in 8.1% (168/2,062) of cases, and in adjusted models, the risk for the composite outcome was significantly higher with SD requiring ≥3 maneuvers (15.1%) versus <3 maneuvers (6.5%; aIRR: 2.08; 95% CI: 1.50-2.89). Additionally, APGAR <5 at 5 minutes (aIRR: 4.10; 95% CI: 1.18-14.25), neonatal brachial plexus palsy (aIRR: 2.58; 95% CI: 1.45-4.60), and hypoxic-ischemic encephalopathy (aIRR: 2.83; 95% CI: 1.36 and 5.89) were significantly more likely when ≥3 were used. No significant difference was noted for postpartum hemorrhage (PPH) by number of maneuvers (aIRR: 0.74; 95% CI: 0.44 and 1.21).SD relieved by ≥3 maneuvers, compared with <3, was associated with a 2-fold-increased risk for the composite neonatal adverse outcome, with no difference in risk for PPH. · ≥3 Maneuvers increase neonatal adverse outcomes.. · With ≥3 maneuvers, higher risk of low APGAR and HIE.. · PPH rates similar for ≥3 versus <3 maneuvers..

Adverse perinatal events and subsequent cesarean rate

Management of anticipated and actual shoulder dystocia: Interpreting the literature

Objective First, to analyze the impact on induction of labor, cesarean section and shoulder dystocia (ShD) rates after the application of an active management protocol in suspected isolated fetal macrosomia. Second, to determine the diagnostic yield of the third trimester scan for the prediction of neonatal macrosomia. Third, to compare baseline characteristics and perinatal outcomes in women with neonates ≥4000 g with and without prenatal suspicion of macrosomia. Methods A retrospective cohort study was conducted between July 2021 and July 2022 in a tertiary center. An active management protocol in suspected fetal macrosomia (estimated fetal weight (EFW) ≥97 custom percentile) after the third-trimester routine scan (between 34 + 0/35 + 6 weeks) in non-complicated pregnancies was applied. A 100-g oral glucose tolerance test (OGTT) was performed to rule out late-onset diabetes and a follow-up scan at 38–39 weeks scheduled. If the EFW was ≥4000 g in this second scan, labor induction within 2–4 days was offered. Maternal and perinatal outcomes were compared in macrosomic newborns (≥4000 g) according to prenatal suspicion of macrosomia. Results A total of 3543 deliveries were registered during the study period. 2832/3543 (79.9%) underwent their third-trimester routine scan, and in 197/2832 (6.9%) fetal macrosomia was suspected. In 147/197 (74.6%) OGTT was performed: 125/147 (85%) were normal and 22/147 (15%) were altered and excluded from further analysis. Among non-diabetic patients 125/125 (100%) had their follow-up scan of which 45/125 (36%) fetuses had an EFW ≥4000 g and 32/45 (71.1%) patients opted for an elective labor induction due to suspected fetal macrosomia (the rest did not meet induction criteria or initiated spontaneous onset of labor). The average neonatal weight in this group was 3975 ± 285 g. The mode of delivery was vaginal birth in 51.1% (23/45) and c-section in 48.9% (22/45). There were four cases of ShD among the 45 vaginal deliveries (8.9%). No perineal tears were diagnosed. Neonatal macrosomia after attempted vaginal birth was identified in 149 cases during the study period, of which 47/149 (31.5%) were antenatally suspected. When comparing the baseline characteristics and outcomes of prenatally suspected vs. unsuspected macrosomic newborns, differences were found in pregestational maternal body mass index (26.9 ± 5.7 vs. 25.9 ± 4.6, p = .03), maternal weight gain (kg) (12.8 ± 4.9 vs. 11.3 ± 4.8, p = .04), neonatal weight (g) (4198 ± 186 vs. 4177 ± 136, p = .04) and need of labor induction (68.1% vs. 44.1%, p = .04) but no differences were found in mode of delivery, ShD or perineal tear rates. Conclusions Third-trimester scan offers low detection rates of neonatal macrosomia. Prenatal macrosomia suspicion during the third trimester followed by active management did not improve perinatal results in this study when compared to non-suspected neonatal macrosomia.

The Zavanelli manoeuvre in shoulder dystocia: case report and review of published cases

Is clavicular fracture protective against brachial plexus palsy?

Midline episiotomy is a known major risk factor for severe perineal lacerations. The study was aimed to define obstetric risk factors for third-degree perineal tears in a university medical center where midline episiotomies are not performed. A comparison between vaginal deliveries complicated with third-degree perineal tears and deliveries without third-degree perineal tears was performed. Deliveries occurred between the years 1988-1999 in a tertiary medical center. Multiple gestations, preterm deliveries (<37 weeks' gestation), cesarean deliveries and cases of shoulder dystocia were excluded from the analysis. A multiple logistic regression model was constructed in order to find independent risk factors for third-degree perineal tears. Odds ratios (OR) and their 95% confidence interval (CI) were calculated from the regression coefficient. During the study period, 79 (0.1%) consecutive cases of third degree perineal tears were identified. Significant risk factors from the univariate analysis were fetal macrosomia (OR 2.7, 95% CI 1.2-5.5), nulliparity (OR 2.9, 95% CI 1.8-4.6), labor induction (OR 1.9, 95% CI 1.0-3.5), failure of labor to progress during the second stage (OR 10.8, 95% CI 5.4-21.1), non-reassuring fetal heart rate patterns (OR 11.7, 95% CI 6.1-21.5), mediolateral episiotomy (OR 2.8, 95% CI 1.8-4.5), vacuum extraction (OR 10.6, 95% CI 6.1-18.3), and forceps delivery (OR 29.2, 95% CI 7.3-97.2). However, using a multivariable analysis, only fetal macrosomia (OR 2.5, 95% CI 1.2-4.9), vacuum extraction (OR 8.2, 95% CI 4.7-14.5), and forceps delivery (OR 26.7, 95% CI 8.0-88.5) remained as independent risk factors. The combined risk for instrumental deliveries of macrosomic newborns was 8.6 (95% CI 1.2-62.5; p=0.010). After adjustment for possible confounding variables, mediolateral episiotomy per se was not an independent risk factor for third-degree perineal tears. Instrumental vaginal deliveries of macrosomic fetuses should be avoided whenever possible to decrease the occurrence of third-degree perineal tears.

EMERGENT MANAGEMENT OF SHOULDER DYSTOCIA

To evaluate the relationship between the head-to-body delivery interval in shoulder dystocia, persistent brachial plexus injury, and neonatal depression. We compared the head-to-body delivery intervals in 127 cases of uncomplicated shoulder dystocia-identified using medical record coding and verified by chart review in a university--affiliated community hospital--with a series of 55 medical-legal cases of shoulder dystocia with persistent brachial plexus injury, 14 of which included neonatal depression. Neonatal depression was defined as the presence of any of the following: fetal demise, cardiopulmonary resuscitation, intubation, umbilical artery pH lower than 7.00, or 5-minute Apgar score of 5 or lower. In the uncomplicated shoulder dystocia group, the median head-to-body delivery interval was 1.0 minute (interquartile range 0.5-1.0). The median for neonates with persistent brachial plexus injury and no depression was 2.0 minutes (interquartile range 1.0-4.0). For those with both persistent brachial plexus injury and neonatal depression, the median was significantly longer at 5.3 minutes (interquartile range 3.9-13.3), P<.001. Neonates born with persistent brachial plexus injury and neonatal depression after shoulder dystocia had longer head-to-body delivery intervals than those with uncomplicated shoulder dystocia or shoulder dystocia with persistent brachial plexus injury without depression. By 4 minutes, all of the neonates with uncomplicated shoulder dystocia were born. Conversely, the majority of neonates with depression-57%-had head-to-body delivery intervals greater than 4 minutes. Such information offers guidance to clinicians caught between the admonition to apply only gentle force when utilizing maneuvers to accomplish a shoulder dystocia delivery and the countervailing need to achieve delivery within a critical time frame to prevent hypoxic injury. III.