UNASSIGNED: Macrosomia represents the most significant risk factor of shoulder dystocia (SD), which is a severe and emergent complication of vaginal delivery. They are both associated with adverse pregnancy outcomes.
UNASSIGNED: The aim of this study was to review and compare the most recently published influential guidelines on the diagnosis and management of fetal macrosomia and SD.
UNASSIGNED: A comparative review of guidelines from the American College of Obstetricians and Gynecologists (ACOG), the Royal College of Obstetricians and Gynaecologists, the National Institute for Health and Care Excellence, the Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG), and the Department for Health and Wellbeing of the Government of South Australia on macrosomia and SD was conducted.
UNASSIGNED: The ACOG and RANZCOG agree that macrosomia should be defined as birthweight above 4000-4500 g regardless of the gestational age, whereas the National Institute for Health and Care Excellence defines macrosomia as an estimated fetal weight above the 95th percentile. According to ACOG and RANZCOG, ultrasound scans and clinical estimates can be used to rule out fetal macrosomia, although lacking accuracy. Routine induction of labor before 39 weeks of gestation with the sole indication of suspected fetal macrosomia is unanimously not recommended, but an individualized counseling should be provided. Exercise, appropriate diet, and prepregnancy bariatric surgery are mentioned as preventive measures. There is also consensus among the reviewed guidelines regarding the definition and the diagnosis of SD, with the \"turtle sign\" being the most common sign for its recognition as well as the poor predictability of the reported risk factors. Moreover, there is an overall agreement on the algorithm of SD management with McRoberts technique suggested as first-line maneuver. In addition, appropriate staff training, thorough documentation, and time keeping are crucial aspects of SD management according to all medical societies. Elective delivery for the prevention of SD is discouraged by all the reviewed guidelines.
UNASSIGNED: Macrosomia is associated not only with SD but also with maternal and neonatal complications. Similarly, SD can lead to permanent neurologic sequalae, as well as perinatal death if managed in a suboptimal way. Therefore, it is crucial to develop consistent international practice protocols for their prompt diagnosis and effective management in order to safely guide clinical practice and improve pregnancy outcomes.

A recent randomized controlled trial suggested that early gestational diabetes mellitus (GDM) screening in patients with obesity (body mass index [BMI] ≥30 kg/m2) does not improve perinatal outcomes. The American College of Obstetrics and Gynecology currently recommends early screening for gestational diabetes in patients who are overweight with one or more additional risk factors. We evaluated the effect of screening based on the number of additional risk factors for development of gestational diabetes.
This was a secondary analysis of a multicenter randomized controlled trial of obese patients with singleton nonanomalous fetuses comparing early (14-20 weeks\' gestation) with routine (24-28 weeks\' gestation) GDM screening. Exclusion criteria were pregestational diabetes, major medical illnesses, bariatric surgery, chronic steroid use, and prior cesarean. Early versus routine GDM screening groups were compared and stratified by the number of additional risk factors for GDM (0, 1, 2, and ≥3). The primary outcome was an adverse perinatal composite outcome composed of: macrosomia, primary cesarean delivery, hypertensive disorders of pregnancy, shoulder dystocia, neonatal hyperbilirubinemia, and neonatal hypoglycemia. Analyses examined effects of early versus routine screening by the number of additional risk factors and their possible interaction on the incidences of the primary outcome and GDM.
Of 913 patients, 5% had 0, 52% had 1, 33% had 2, and 10% had ≥3 additional risk factors. Baseline characteristics, including the number and type of risk factors, were similar between early and routine screening groups. Breslow-Day test for interaction between early versus routine screening and the number of additional risk factors was not significant for either the primary outcome (p = 0.37) or the diagnosis of GDM (p = 0.28). The incidence of GDM and the adverse perinatal composite outcome increased as the number of risk factors increased (p < 0.001).
In patients with BMI ≥30 kg/m2 and additional risk factors, early GDM screening does not prevent adverse outcomes.
· The ACOG currently recommends early screening for gestational diabetes if patients have risk factors.. · Even in patients with multiple risk factors, early screening for GDM does not improve outcomes.. · Patients with three or more risk factors may have worse outcomes if they undergo early screening..

Shoulder dystocia (SD) is defined as a vaginal delivery in cephalic presentation that requires additional obstetric maneuvers to deliver the fetus after the head has delivered and gentle traction has failed. It complicates 0.5-1% of vaginal deliveries. Risks of brachial plexus birth injury (level of evidence [LE]3), clavicle and humeral fracture (LE3), perinatal asphyxia (LE2), hypoxic-ischemic encephalopathy (LE3) and perinatal mortality (LE2) increase with SD. Its main risk factors are previous SD and macrosomia, but both are poorly predictive; 50-70% of SD cases occur in their absence, and most deliveries when they are present do not result in SD. No study has proven that the correction of these risk factors (except gestational diabetes) would reduce the risk of SD. Physical activity is recommended before and during pregnancy to reduce the occurrence of some risk factors for SD (Grade C). In obese women, physical activity should be coupled with dietary measures to reduce fetal macrosomia and weight gain during pregnancy (Grade A). Women with gestational diabetes require diabetes care (diabetic diet, glucose monitoring, insulin if needed) (Grade A) because it reduces the risk of macrosomia and SD (LE1). Only two measures are proposed for avoiding SD and its complications. First, induction of labor is recommended in cases of impending macrosomia if the cervix is favorable at a gestational age of 39 weeks or more (professional consensus). Second, cesarean delivery is recommended before labor in three situations and during labor in one: (i) estimated fetal weight (EFW) >4500g if associated with maternal diabetes (Grade C), (ii) EFW >5000g in women without diabetes (Grade C), (iii) history of SD associated with severe neonatal or maternal complications (professional consensus), and finally during labor, (iv) in case of fetal macrosomia and failure to progress in the second stage, when the fetal head station is above +2 (Grade C). In cases of SD, it is recommended to avoid the following actions: excessive traction on the fetal head (Grade C), fundal pressure (Grade C), and inverse rotation of the fetal head (professional consensus). The McRoberts maneuver, with or without suprapubic pressure, is recommended first (Grade C). If it fails and the posterior shoulder is engaged, Wood\'s maneuver should be performed preferentially; if the posterior shoulder is not engaged, it is preferable to attempt to deliver the posterior arm next (professional consensus). It appears necessary to know at least two maneuvers to perform should the McRoberts maneuver fail (professional consensus). A pediatrician should be immediately informed of SD. The initial clinical examination should check for complications, such as brachial plexus injury or clavicle fracture (professional consensus). If no complications are observed, neonatal monitoring need not be modified (professional consensus). The implementation of practical training with simulation for all care providers in the delivery room is associated with a significant reduction in neonatal (LE3) but not maternal (LE3) injury. SD remains an unpredictable obstetric emergency. All physicians and midwives should know and perform obstetric maneuvers if needed, quickly but calmly.

OBJECTIVE: To determine the available evidence to prevent and treat shoulder dystocia to attempt to decrease its related neonatal and maternal morbidity.
METHODS: The PubMed database, the Cochrane Library and the recommendations from the French and foreign obstetrical societies or colleges have been consulted.
RESULTS: Shoulder dystocia, defined as a vaginal delivery that requires additional obstetric maneuvers to deliver the fetus after the head has delivered and gentle traction has failed, complicates 0.5-1 % of vaginal deliveries. Risks of brachial plexus birth injury (LE3), clavicle and humeral fracture (LE3), perinatal asphyxia (LE2), hypoxic-ischemic encephalopathy (LE3) and perinatal mortality (LE2) are increased after shoulder dystocia. Its main risk factors are previous shoulder dystocia and macrosomia, but they are poorly predictive; 50 % to 70 % of shoulder dystocia cases occur in their absence, and the great majority of deliveries when they are present are not associated with shoulder dystocia. No study has proven that the correction of these risk factors (except gestational diabetes) would reduce the risk of shoulder dystocia (SD). Physical activity is recommended before and during pregnancy to reduce the occurrence of some risk factors for shoulder dystocia (grade C). In obese patients, physical activity should be coupled with dietary measures to reduce fetal macrosomia and weight gain during pregnancy (grade A). In case of gestational diabetes, diabetes care is recommended (diabetic diet, glucose monitoring, insulin if needed) (grade A) as it reduces the risk of macrosomia and shoulder dystocia (LE1). In order to avoid shoulder dystocia and its complications, only two measures are proposed. Induction of labor is recommended in case of impending macrosomia if the cervix is favourable and gestational age greater than 39 weeks of gestation (professional consensus). Cesarean delivery is recommended before labor in case of EFW greater than 4500g if associated with maternal diabetes (grade C), EFW greater than 5000g in the absence of maternal diabetes (grade C), history of shoulder dystocia associated with severe neonatal or maternal complications (Professional consensus), and finally during labor, in case of fetal macrosomia and failure to progress in the second stage, when the fetal head is above a +2 station (grade C). In case of shoulder dystocia, it is recommended not to pull excessively on the fetal head (grade C), do not perform uterine expression (grade C) and do not realize inverse rotation of the fetal head (professional consensus). McRoberts\' maneuver, with or without a suprapubic pressure, is recommended in the first line (grade C). In case of failure, if the posterior shoulder is engaged, Wood\'s maneuver should be performed preferentially; if the posterior shoulder is not engaged, delivery of the posterior arm should be performed preferentially (professional consensus). It seems necessary to know at least two maneuvers to perform in case of shoulder dystocia unresolved by the maneuver of McRoberts (professional consensus). Pediatrician should be immediately informed in case of shoulder dystocia. The initial clinical examination should search complications such as brachial plexus birth injury or clavicle fracture (professional consensus). In absence of neonatal complication, monitoring of the neonate is not modified (professional consensus). The implementation of a practical training using simulation and concerning all caregivers of the delivery room is associated with a significant reduction in neonatal (LE3) but not maternal (LE3) injury.
CONCLUSIONS: Shoulder dystocia remains a non-predictable obstetrics emergency. All physicians and midwives should know and perform obstetric maneuvers if needed quickly but without precipitation. A training program using simulation for the management of shoulder dystocia is encouraged for the initial and continuing formation of different actors in the delivery room (professional consensus).