Prophylactic cesarean delivery for fetal macrosomia diagnosed by means of ultrasonography--A Faustian bargain?

Fetal Growth Biometry as Predictors of Shoulder Dystocia in a Low-Risk Obstetrical Population

OBJECTIVE

This study aimed to evaluate fetal biometrics as predictors of shoulder dystocia (SD) in a low-risk obstetrical population.

STUDY DESIGN

Participants were enrolled as part of a U.S.-based prospective cohort study of fetal growth in low-risk singleton gestations (n = 2,802). Eligible women had liveborn singletons ≥2,500 g delivered vaginally. Sociodemographic, anthropometric, and pregnancy outcome data were abstracted by research staff. The diagnosis of SD was based on the recorded clinical impression of the delivering physician. Simple logistic regression models were used to examine associations between fetal biometrics and SD. Fetal biometric cut points, selected by Youden's J and clinical determination, were identified to optimize predictive capability. A final model for SD prediction was constructed using backward selection. Our dataset was randomly divided into training (60%) and test (40%) datasets for model building and internal validation.

RESULTS

A total of 1,691 women (98.7%) had an uncomplicated vaginal delivery, while 23 (1.3%) experienced SD. There were no differences in sociodemographic or maternal anthropometrics between groups. Epidural anesthesia use was significantly more common (100 vs. 82.4%; p = 0.03) among women who experienced SD compared with those who did not. Amniotic fluid maximal vertical pocket was also significantly greater among SD cases (5.8 ± 1.7 vs. 5.1 ± 1.5 cm; odds ratio = 1.32 [95% confidence interval: 1.03,1.69]). Several fetal biometric measures were significantly associated with SD when dichotomized based on clinically selected cut-off points. A final prediction model was internally valid with an area under the curve of 0.90 (95% confidence interval: 0.81, 0.99). At a model probability of 1%, sensitivity (71.4%), specificity (77.5%), positive (3.5%), and negative predictive values (99.6%) did not indicate the ability of the model to predict SD in a clinically meaningful way.

CONCLUSION

Other than epidural anesthesia use, neither sociodemographic nor maternal anthropometrics were significantly associated with SD in this low-risk population. Both individually and in combination, fetal biometrics had limited ability to predict SD and lack clinical usefulness.

KEY POINTS

· SD unpredictable in low-risk women.. · Fetal biometry does not reliably predict SD.. · Epidural use associated with increased SD risk.. · SD prediction models clinically inefficient..

Association between Diabetes in Pregnancy and Shoulder Dystocia by Infant Birth Weight in an Era of Cesarean Delivery for Suspected Macrosomia

OBJECTIVE

 We estimated the association between diabetes and shoulder dystocia by infant birth weight subgroups (<4,000, 4,000-4,500, and >4,500 g) in an era of prophylactic cesarean delivery for suspected macrosomia.

STUDY DESIGN

 A secondary analysis from the National Institute of Child Health and Human Development U.S. Consortium for Safe Labor of deliveries at ≥24 weeks with a nonanomalous, singleton fetus with vertex presentation undergoing a trial of labor. The exposure was either pregestational or gestational diabetes compared with no diabetes. The primary outcome was shoulder dystocia and secondarily, birth trauma with a shoulder dystocia. We calculated adjusted risk ratios (aRRs) with modified Poison's regression between diabetes and shoulder dystocia and the number needed to treat (NNT) to prevent a shoulder dystocia with cesarean delivery.

RESULTS

 Among 167,589 assessed deliveries (6% with diabetes), pregnant individuals with diabetes had a higher risk of shoulder dystocia at birth weight <4,000 g (aRR: 1.95; 95% confidence interval [CI]: 1.66-2.31) and 4,000 to 4,500 g (aRR: 1.57; 95% CI: 1.24-1.99), albeit not significantly at birth weight >4,500 g (aRR: 1.26; 95% CI: 0.87-1.82) versus those without diabetes. The risk of birth trauma with shoulder dystocia was higher with diabetes (aRR: 2.29; 95% CI: 1.54-3.45). The NNT to prevent a shoulder dystocia with diabetes was 11 and 6 at ≥4,000 and >4,500 g, versus without diabetes, 17 and 8 at ≥4,000 and >4,500 g, respectively.

CONCLUSION

 Diabetes increased the risk of shoulder dystocia, even at lower birth weight thresholds than at which cesarean delivery is currently offered. Guidelines providing the option of cesarean delivery for suspected macrosomia may have decreased the risk of shoulder dystocia at higher birth weights.

KEY POINTS

· >Diabetes increased the risk of shoulder dystocia, even at lower birth weight thresholds than at which cesarean delivery is currently offered.. · Cesarean delivery for suspected macrosomia may have decreased the risk of shoulder dystocia at higher birth weights.. · These findings can inform delivery planning for providers and pregnant individuals with diabetes..

Considering Criteria for Active Phase Labor Management of Nulliparous Women: A Cost-Effectiveness Analysis

OBJECTIVE

The aim of the study is to evaluate differences in maternal and neonatal outcomes based on updated criteria for defining active labor at 6 cm of cervical dilation and to determine if these recommendations are cost-effective.

STUDY DESIGN

A decision-analytic model was built using TreeAge Pro 2020 software. We included maternal outcomes of mode of delivery, endometritis, postpartum hemorrhage requiring transfusion, and death. Neonatal outcomes included rates of shoulder dystocia and permanent brachial plexus injury. Costs and quality-adjusted life years (QALYs) were included from the maternal and infant perspectives. We used a willingness-to-pay threshold of $100,000 per QALY and all model inputs were subjected to sensitivity analysis.

RESULTS

In a theoretical cohort of 1.4 million women, a threshold of 6 cm to define active labor resulted in 373,668 fewer cesarean deliveries, 33,181 fewer cases of endometritis, 143 fewer postpartum hemorrhages requiring transfusions, and seven fewer maternal deaths when compared with a threshold of 4 cm. However, there were higher rates of adverse neonatal outcomes, including 484 more cases of shoulder dystocia and 17 more instances of permanent brachial plexus injury. Using 6 cm as the threshold resulted in lower costs and greater effectiveness, making it a dominant strategy. Multivariate sensitivity analysis demonstrated the model was robust over a wide range of assumptions.

CONCLUSION

In this model, considering 6 cm of cervical dilation as the threshold for the active phase of labor compared with 4 cm was a cost-effective strategy to prevent primary cesarean deliveries, lower costs, and improve maternal outcomes, despite associated increased adverse neonatal outcomes.

KEY POINTSG

· Cervical dilation of 6 cm should be considered the threshold for the active phase of labor. This is a change from the prior definition of 4 cm.. · We built a theoretical model to compare outcomes and costs associated with the new active phase definition of 6 cm.. · Using a 6-cm threshold is a cost-effective strategy for decreasing primary cesarean deliveries..

Antenatal risk score for prediction of shoulder dystocia with focus on fetal ultrasound data

BACKGROUND

Shoulder dystocia is one of the most threatening complications during delivery, and although it is difficult to predict, individual risk should be considered when counseling for mode of delivery.

OBJECTIVE

This study aimed to develop and validate a risk score for shoulder dystocia based on fetal ultrasound and maternal data from 15,000 deliveries.

STUDY DESIGN

Data were retrospectively obtained of deliveries in 3 tertiary centers between 2014 and 2017 for the derivation cohort and between 2018 and 2020 for the validation cohort. Inclusion criteria were singleton pregnancy, vaginal delivery in cephalic presentation at ≥37+0 weeks' gestation, and fetal biometry data available within 2 weeks of delivery. Independent predictors were determined by multivariate regression analysis in the derivation cohort, and a score was developed on the basis of the effect of the predictors.

RESULTS

The derivation cohort consisted of 7396 deliveries with a 0.91% rate of shoulder dystocia, and the validation cohort of 7965 deliveries with a 1.0% rate of shoulder dystocia. Among all women, 13.8% had diabetes mellitus, and 12.1% were obese (body mass index ≥30 kg/m2). Independent risk factors in the derivation cohort were: estimated fetal weight ≥4250 g (odds ratio, 4.27; P=.002), abdominal-head-circumference ≥2.5 cm (odds ratio, 3.96; P<.001), and diabetes mellitus (odds ratio, 2.18; P=.009). On the basis of the strength of effect, a risk score was developed: estimated fetal weight ≥4250 g=2, abdominal-head-circumference ≥2.5 cm=2, and diabetes mellitus=1. The risk score predicted shoulder dystocia with moderate discriminatory ability (area under the receiver-operating characteristic curve, 0.69; P<.001; area under the receiver-operating characteristic curve, 0.71; P<.001) and good calibration (Hosmer-Lemeshow goodness-of-fit; P=.466; P=.167) for the derivation and validation cohorts, respectively. With 1 score point, 16 shoulder dystocia cases occurred in 1764 deliveries, with 0.6% shoulder dystocia incidence and a number needed to treat with cesarean delivery to avoid 1 case of shoulder dystocia of 172 (2 points: 38/1809, 2.1%, 48; 3 points: 18/336, 5.4%, 19; 4 points: 10/96, 10.5%, 10; and 5 points: 5/20, 25%, 4); 40.8% of the shoulder dystocia cases occurred without risk factors.

CONCLUSION

The presented risk score for shoulder dystocia may act as a supplemental tool for the clinical decision-making regarding mode of delivery. According to our score model, in pregnancies with a score ≤2, meaning having solely estimated fetal weight ≥4250 g, or abdominal-head-circumference ≥2.5, or diabetes mellitus, cesarean delivery for prevention of shoulder dystocia should not be recommended because of the high number needed to treat to avoid 1 case of shoulder dystocia. Conversely, in patients with a score of ≥4 with or without diabetes mellitus, cesarean delivery may be considered. However, in 40% of the shoulder dystocia cases, no risk factors had been present.

Accuracy of Fetal Biacromial Diameter and Derived Ultrasonographic Parameters to Predict Shoulder Dystocia: A Prospective Observational Study

Background and Objectives: Shoulder dystocia (ShD) is one of most dangerous obstetric complication. The objective of this study was to determine if the ultrasonographic fetal biacromial diameter (BA) and derived parameters could predict ShD in uncomplicated term pregnancies. Materials and Methods: We conducted a prospective observational study in a tertiary care university hospital from March 2021 to February 2022. We included all full-term pregnancies accepted for delivery that received an accurate ultrasonography (USG) scan before delivery. USG biometry and estimated fetal weight (EFW) were collected. Therefore, we evaluated the diameter of the mid-arm, the transverse thoracic diameter (TTD) and the biacromial diameter (BA). BA was estimated using Youssef’s formula: TTD + 2 mid-arm diameters. The primary outcome was the evaluation of BA and its related parameters (BA/biparietal diameter (BPD), BA/head circumference (HC) and BA–BPD in fetuses with ShD versus fetuses without ShD. Diagnostic accuracy for ShD of BA, BA/BPD, BA/HC and BA–BPD was evaluated using receiver operator curve (ROC) analysis. Results: 90 women were included in the analysis, four of these had ShD and required extra maneuvers after head delivery. BA was increased in fetuses with ShD (150.4 cm; 95% CI 133.2 cm to 167.6 cm) compared to no-ShD (133.5 cm; 95% CI 130.1 cm to 137.0 cm; p = 0.04). Significant differences were also found between ShD and no-ShD groups for BA/BPD (1.66 (95% CI 1.46 to 1.86) vs. 1.44 (95% CI 1.41 to 1.48); p = 0.04), BA/HC (0.45 (95% CI 0.40 to 0.49) vs. 0.39 (95% CI 0.38 to 0.40); p = 0.01), BA–BPD (60.0 mm (95% CI 42.4 to 77.6 cm) vs. 41.4 (95% CI 38.2 to 44.6); p = 0.03), respectively. ROC analysis showed an overall good accuracy for ShD, with an AUC of 0.821 (p = 0.001) for BA alone and 0.881 (p = 0.001), 0.857 (p = 0.016) and 0.867 (p = 0.013) for BA/BPD, BA–BPD and BA/HC, respectively. Conclusions: BA alone, as well as BA/BPD, BA/HC and BA–BPD might be useful predictors of ShD in uncomplicated term pregnancies. However, such evidence needs extensive confirmation by means of additional studies with large sample sizes, especially in case of pregnancies at high risk for ShD (i.e., gestational diabetes).

Timing of active phase labor arrest diagnosis in nulliparous women: a cost-effectiveness analysis

BACKGROUND

Recommendations from the American College of Obstetricians and Gynecologists for the safe prevention of primary cesarean deliveries propose that cesarean delivery for active phase arrest in the first stage of labor should be performed only if women fail to progress despite four hours of adequate uterine activity and no cervical change. This is a change in recommendation from a two-hour threshold.

OBJECTIVE

To determine the economic and clinical implications of waiting four hours compared to two hours for cervical progression before diagnosing active phase labor arrest.

STUDY DESIGN

We designed a cost-effectiveness analysis using TreeAge Pro 2020 software with model inputs derived from the literature. We used a theoretical cohort of 1.4 million women, the approximate number of nulliparous U.S. women reaching four centimeters in spontaneous labor. We compared maternal and neonatal outcomes and costs associated with defining active phase arrest after four hours of no cervical progression versus two hours. As a baseline assumption, active labor was defined at four centimeters. It was assumed that women with active phase arrest were delivered via cesarean delivery. In addition to cost and maternal quality-adjusted life years (QALY), outcomes included mode of delivery, endometritis, postpartum hemorrhage requiring transfusion, and maternal deaths. Neonatal outcomes included rates of shoulder dystocia and permanent brachial plexus injury. The willingness-to-pay threshold was set at $100,000/QALY.

RESULTS

In a theoretical cohort of 1.4 million women, waiting four hours instead of two hours led to 322,253 fewer cesarean deliveries, 6 fewer maternal deaths, 123 fewer postpartum hemorrhages requiring transfusions, and 28,615 fewer episodes of endometritis. There were 418 more instances of neonatal shoulder dystocia and 14 more cases of permanent brachial plexus injuries with a four-hour threshold. A four-hour threshold leads to 56% more women having a vaginal delivery in our theoretical cohort. Results from our model show that waiting four hours versus two hours to diagnose active phase labor arrest led to increased total QALYs with increased costs, with an incremental cost effectiveness ratio (ICER) below our willingness-to-pay threshold of $100,000 per QALY. Thus, it was cost effective to wait for at least four hours in the diagnosis of active phase arrest. Multivariable sensitivity analysis demonstrated the model was robust over a wide range of assumptions.

CONCLUSIONS

Increasing the time threshold from two to four hours for diagnosing active phase labor arrest beyond four centimeters is a cost-effective strategy, resulting in fewer primary cesarean deliveries and improved maternal outcomes, despite a small increase in adverse neonatal outcomes.

Rising trends in the incidence of shoulder dystocia and development of a novel shoulder dystocia risk score tool: a nationwide population-based study of 800 484 Finnish deliveries

INTRODUCTION

Shoulder dystocia has remained an unpredictable and feared emergency in obstetrics. Some risk factors have been identified but nevertheless there is a lack of risk evaluation tools in clinical practice. The aim of this study was to evaluate the incidence and risk factors of shoulder dystocia in the Finnish population and to develop a shoulder dystocia risk score tool.

MATERIAL AND METHODS

This retrospective, population-based study included all deliveries in Finland between 2004 and 2017 (n = 800 484). The annual numbers of shoulder dystocia diagnoses were gathered from nationwide Finnish Medical Birth Register and Hospital Discharge Register. The incidence of shoulder dystocia was calculated in subgroups according to the mode of delivery, maternal diabetes status, body mass index (BMI), age, parity and gestational age. Based on these numbers, a shoulder dystocia risk score tool was created.

RESULTS

The overall incidence of shoulder dystocia was 0.18%. It increased significantly during the study period from 0.10% to 0.32% (P < .001). More specifically, the incidence increased significantly in all analyzed subgroups except for women with BMI <18.5 or age <20 years. To evaluate the importance of risk factors, practical and simple shoulder dystocia risk score tool was created. Instrumental vaginal delivery, maternal diabetes of any kind, BMI ≥25, age ≥40 years and gestational age ≥41 weeks were associated with higher shoulder dystocia risk compared with non-diabetic, non-obese and younger women with spontaneous deliveries before 41 weeks of gestation. In our risk score tool, cases with shoulder dystocia had a significantly higher number of risk points than those without it (15.2 vs 10.4, P < .001). The risk was significantly high when the scores were ≥18 points (relative risk 9.54, 95% confidence interval 8.61-10.57).

CONCLUSIONS

The incidence of shoulder dystocia in Finland increased during the study period but it is still low compared with previous studies from other countries. In clinical daily practice, the new shoulder dystocia risk score tool helps to evaluate the individual risk profile of the parturient. According to this risk score tool, the highest risk was found with the combination of instrumental vaginal delivery, maternal diabetes, BMI ≥25, age ≥40 years and gestational age ≥41 weeks.

Risk factors for neonatal brachial plexus palsy: a systematic review and meta-analysis

AIM

To provide a comprehensive update on the most prevalent, significant risk factors for neonatal brachial plexus palsy (NBPP).

METHOD

Cochrane CENTRAL, MEDLINE, Web of Science, Embase, and ClinicalTrials.gov were searched for relevant publications up to March 2019. Studies assessing risk factors of NBPP in relation to typically developing comparison individuals were included. Meta-analysis was performed for the five most significant risk factors, on the basis of the PRISMA statement and MOOSE guidelines. Pooled odds ratios (ORs), 95% confidence intervals (CIs), and across-study heterogeneity (I² ) were reported. Reporting bias and quality of evidence was rated. In addition, we assessed the incidence of NBPP.

RESULTS

Twenty-two observational studies with a total sample size of 29 419 037 live births were selected. Significant risk factors included shoulder dystocia (OR 115.27; 95% CI 81.35-163.35; I² =92%), macrosomia (OR 9.75; 95% CI 8.29-11.46; I² =70%), (gestational) diabetes (OR 5.33; 95% CI 3.77-7.55; I² =59%), instrumental delivery (OR 3.8; 95% CI 2.77-5.23; I² =77%), and breech delivery (OR 2.49; 95% CI 1.67-3.7; I² =70%). Caesarean section appeared as a protective factor (OR 0.13; 95% CI 0.11-0.16; I² =41%). The pooled overall incidence of NBPP was 1.74 per 1000 live births. It has decreased in recent years.

INTERPRETATION

The incidence of NBPP is decreasing. Shoulder dystocia, macrosomia, maternal diabetes, instrumental delivery, and breech delivery are risk factors for NBPP. Caesarean section appears as a protective factor.

WHAT THIS PAPER ADDS

The overall incidence of neonatal brachial plexus palsy is 1.74 per 1000 live births. The incidence has declined significantly. Shoulder dystocia, macrosomia, maternal diabetes, instrumental delivery, and breech delivery are the main risk factors. Prevention is difficult owing to unpredictability and often labour-related risk.

An agency model of consent and the standards of disclosure in health care: Knowing-how to reach respectful shared decisions among real persons

OBJECTIVE

In this article, we evaluate and compare the frailties of two different standards of disclosure of information regarding the risks of medical procedures applied in recent judicial decisions in the United Kingdom. As an alternative, we present the tenets and philosophical grounds of an agency model of consent and a person-based standard of disclosure.

METHODS

Critical philosophical analysis of the background assumptions of two standards of disclosure and their relative "tests of negligence" applied in recent legal judgements in the United Kingdom.

RESULTS

Both standards, the "Professional Practice Standard" (the traditional standard employed in Sidaway versus Board of Governors of the Bethlem Royal Hospital, 1985) and the allegedly new "Reasonable Person Standard" (mentioned in Montgomery versus Lanarkshire Health Board, 2015), can lead to malpractice if the medical-patient relationship is not guided by attitudes of respectful care. The traditional standard is disrespectful as it does not take patients as full agents, presupposing that the patient's right is only a negative right to refuse what was deliberated only by the practitioner. The "new" standard can be disrespectful if the practitioner, concerned only with what a hypothetical reasonable individual would take as relevant for choosing between alternatives of treatment, does not know how to respect their real patient in a genuine shared decision-making process.

CONCLUSION

We conclude that in order to know how to obtain valid informed consent, doctors need to engage in real conversations with their patients, revealing as much information as they, taken as real persons, need to be part of a genuine shared and respectful decision-making process.

Surgical Technique and Anatomical Considerations for the Modified L'Episcopo Tendon Transfer

BACKGROUND

Birth brachial plexus injury usually affects the upper trunks of the brachial plexus and can cause substantial loss of active shoulder external rotation and abduction. Due to the unbalanced rotational forces acting at the glenohumeral joint, the natural history of the condition involves progressive glenohumeral joint dysplasia with associated upper limb dysfunction. Surgical reconstruction methods have been described previously by Sever and L'Episcopo, and modified by Hoffer and Roper to release the adduction contracture and to restore external rotation and shoulder abduction.

METHODS

The authors describe their preferred technique for contracture release and tendon transfer to improve external rotation and shoulder abduction. Pertinent anatomy and highlights of surgical exposure are reviewed.

RESULTS

The senior author has utilized this technique with consistent clinical outcomes to improve shoulder function for patients with persisting nerve palsy associated with birth brachial plexus injury. A review of the literature supports utilization of this technique.

CONCLUSIONS

Transfer of the latissimus dorsi and teres major to the posterior rotator cuff for reanimation of shoulder abduction and external rotation deficits associated with birth brachial plexus injury is a safe and reliable technique. Careful patient selection and attention to surgical detail are critical for optimal outcomes.

Prevention of shoulder dystocia: A randomized controlled trial to evaluate an obstetric maneuver

OBJECTIVE

Shoulder dystocia is a major obstetric emergency defined as a failure of delivery of the fetal shoulder(s). This study evaluated whether an obstetric maneuver, the push back maneuver performed gently on the fetal head during delivery, could reduce the risk of shoulder dystocia.

STUDY DESIGN

We performed a multicenter, randomized, single-blind trial to compare the push back maneuver with usual care in parturient women at term. The primary outcome, shoulder dystocia, was considered to have occurred if, after delivery of the fetal head, any additional obstetric maneuver, beginning with the McRoberts maneuver, other than gentle downward traction and episiotomy was required.

RESULTS

We randomly assigned 522 women to the push back maneuver group (group P) and 523 women to the standard vaginal delivery group (group S). Finally, 473 women assigned to group P and 472 women assigned to group S delivered vaginally. The rate of shoulder dystocia was significantly lower in group P (1·5%) than in group S (3·8%) (odds ratio [OR] 0·38 [0·16-0·92]; P = 0·03). After adjustment for predefined main risk factors, dystocia remained significantly lower in group P than in group S. There were no significant between-group differences in neonatal complications, including brachial plexus injury, clavicle fracture, hematoma and generalized asphyxia.

CONCLUSION

In this trial in 945 women who delivered vaginally, the push back maneuver significantly decreased the risk of shoulder dystocia, as compared with standard vaginal delivery.

Accuracy of immediate antepartum ultrasound estimated fetal weight and its impact on mode of delivery and outcome - a cohort analysis

Background

The aim of the study was to investigate the accuracy of ultrasound-derived estimated fetal weight (EFW) and to determine its impact on management and outcome of delivery.

Methods

In this single-center cohort analysis, women with a singleton term pregnancy in the beginning stages of labor were included. Women with immediately antepartum EFW (N = 492) were compared to women without ultrasound (N = 515).

Results

EFW was correct (deviation from birth weight ≤ 10%) in 72.2% (355/492) of patients with fetal biometry; 19.7% (97/492) were underestimated, and 8.1% (40/492) were overestimated. Newborns with a lower birth weight were more frequently overestimated, and newborns with higher birth weight were more frequently underestimated. The mean difference between EFW and real birth weight was − 114.5 g (standard deviation ±313 g, 95% confidence interval 87.1–142.0). The rate of non-reassuring fetal heart tracing (9.8% vs. 1.9%, P < 0.001) and of caesarean delivery (9.1% vs. 5.0%, P = 0.013) was higher in women with EFW. Overestimation was associated with an increased risk for delivery by caesarean section (odds ratio 2.80; 95% confidence interval 1.2–6.5, P = 0.017). After adjustment, EFW remained associated with increased non-reassuring fetal heart tracing (odds ratio 4.73; 95% confidence interval 2.3–9.6) and caesarean delivery (odds ratio 1.86; 95% confidence interval 1.1–3.1). The incidence of perineal tears of grade 3/4, shoulder dystocia, postnatal depression and neonatal acidosis did not differ between groups.

Conclusions

Antepartum ultrasound-derived EFW does not improve maternal and fetal outcome and is therefore not recommended.

Practice Bulletin No. 173: Fetal Macrosomia

Suspected fetal macrosomia is encountered commonly in obstetric practice. As birth weight increases, the likelihood of labor abnormalities, shoulder dystocia, birth trauma, and permanent injury to the neonate increases. The purpose of this document is to quantify those risks, address the accuracy and limitations of methods for estimating fetal weight, and suggest clinical management for a pregnancy with suspected fetal macrosomia.

Risk Factors for Shoulder Dystocia: the Impact of Mother's Race and Ethnicity

Shoulder dystocia is a rare but severe birth trauma where the neonate's shoulders fail to deliver after delivery of the head. Failure to deliver the shoulders quickly can lead to severe, long-term injury to the infant, including nerve injury, skeletal fractures, and potentially death. This observational study examined shoulder dystocia risk factors by race and ethnicity using a sample of 19,236 pregnant women who presented for labor and delivery from July 1, 2010 until June 30, 2013 at five locations. Multivariate analyses were used to identify risk factors associated with shoulder dystocia occurrence in racial/ethnic groups with high incidence rates. For White non-Hispanic mothers, the strongest risk factors were delivering past 40 weeks' gestation (odds ratio [OR] = 2.4; 95% confidence interval [CI] = 1.5, 3.9; p < .01) and use of epidural anesthesia during delivery (OR = 4.4; 95% CI = 3.0, 6.4; p < .01). Among Black non-Hispanic mothers, the risk factors with the greatest impact were use of epidural (OR = 5.3; 95% CI = 3.2, 8.7; p < .01) and having gestational diabetes and controlling the condition with insulin (OR = 4.6; 95% CI = 1.5, 13.8; p < .01). Additionally, among Hispanic mothers, having Spanish as primary language increased shoulder dystocia likelihood compared to those who did not cite it as their primary language (OR = 2.3; 95% CI = 1.1, 4.6; p < .05). This study provides evidence that risk factors for a labor and delivery condition can vary significantly across racial and ethnic subgroups. These differences emphasize the importance of evaluating risk by population subgroups and might provide a basis for labor and delivery clinicians to enhance personalized medicine to reduce adverse events.

Shoulder dystocia: prediction and management

Shoulder dystocia is a complication of vaginal delivery and the primary factor associated with brachial plexus injury. In this review, we discuss the risk factors for shoulder dystocia and propose a framework for the prediction and prevention of the complication. A recommended approach to management when shoulder dystocia occurs is outlined, with review of the maneuvers used to relieve the obstruction with minimal risk of fetal and maternal injury.

Estimating fetal weight for best clinical outcome

Clinical decisions are often based on the results of third trimester sonograms, particularly with small or large babies and so accuracy of estimating fetal weight (EFW) is essential. There are numerous EFW formula available and yet in Australia no one formula has been recommended for use due to the lack of clinical evidence as to their accuracy. Objectives: 1 To assess inter/intra observer error for fetal parameter measurements with multiple observers. 2 To compare six of the most commonly used EFW formulae and analyse inter/intra formulae variations for different weight range. Method: EFW of 121 pregnancies assessed within 7 days of birth by measuring the BPD, OFD, HC, AC, FL and comparing to actual birth weight. Results: Inter-observer error: 1.3 to 3.1%. Intra-observer error: 1.1 to 1.9% depending on fetal parameter. Accuracy of each EFW formula changed with different weight ranges. For all formulae the highest random error occurred in the macrosomic group. The lowest random error in all weight groups was the Hadlock B formula incorporating the HC/AC/FL (7.7%). Conclusion: Considering the possible problems of head moulding this study suggests the use of: Hadlock FP et al (1982) - Formula B - incorporating HC/AC/FL.

Prevention of shoulder dystocia related birth injuries: Myths and facts

Traditionally, brachial plexus damage was attributed to excessive traction applied on the fetal head at delivery. Recently, it was proposed that most injuries occur spontaneously in utero. The author has studied the mechanism of neurological birth injuries based on 338 actual cases with special attention to (1) fetal macrosomia; (2) maternal diabetes; and (3) methods of delivery. There was a high coincidence between use of traction and brachial plexus injuries. Instrumental extractions increased the risk exponentially. Erb’s palsy following cesarean section was exceedingly rare. These facts imply that spontaneous neurological injury in utero is extremely rare phenomenon. Literary reports show that shoulder dystocia and its associated injuries increased in the United States several-fold since the introduction of active management of delivery in the 1970’s. Such a dramatic change in a stable population is unlikely to be caused by incidental spontaneous events unrelated to external factors. The cited investigations indicate that brachial plexus damage typically is traction related. The traditional technique which precludes traction is the optimal method for avoiding arrest of the shoulders and its associated neurological birth injuries. Effective prevention also requires meticulous prenatal care and elective abdominal delivery of macrosomic fetuses in carefully selected cases.

Neonatal brachial plexus palsy with vaginal birth after cesarean delivery: a case-control study

OBJECTIVE

The objective was to determine the rate of neonatal brachial plexus palsy (NBPP) among women with vaginal birth after cesarean delivery (VBAC) and to compare the peripartum characteristics with control subjects.

STUDY DESIGN

The Maternal-Fetal Medicine Unit cesarean registry data were used to identify nonanomalous singleton pregnancies with VBAC and NBPP at gestational age of ≥37 weeks (term) and 4 control subjects (matched for gestational age and diabetes mellitus status but without brachial injury). Odds ratio (OR) and 95% confidence intervals (CIs) were calculated.

RESULTS

Among 11,313 VBACs at term, there were 23 women with NBPP (rate of 2.0/1000 women). Newborn infants with NBPP, compared with control infants, were significantly more likely to weigh ≥4000 g (48% vs 10%, respectively; OR, 8.45; 95% CI, 2.58-28.44) and to require admission to the neonatal intensive care unit (30% vs 13%; OR, 12.98; 95% CI, 2.61-72.18).

CONCLUSION

Women who desire VBAC should be informed about the low rate of NBPP and, if eligible, encouraged to have a trial of labor after cesarean delivery.

An investigation into utilising gestational body mass index as a screening tool for adverse birth outcomes and maternal morbidities in a group of pregnant women in Khayelitsha

OBJECTIVE

The aim of this study was to investigate the ability of the gestational body mass index (BMI) method to screen for adverse birth outcomes and maternal morbidities.

DESIGN

This was a substudy of a randomised controlled trial, the Philani Mentor Mothers' study.

SETTING AND SUBJECTS

The Philani Mentor Mothers' study took place in a peri-urban settlement, Khayelitsha, between 2009 and 2010. Pregnant women living in the area in 2009-2010 were recruited for the study.

OUTCOME MEASURES

Maternal anthropometry (height and weight) and gestational weeks were obtained at baseline to calculate the gestational BMI, which is maternal BMI adjusted for gestational age. Participants were classified into four gestational BMI categories: underweight, normal, overweight and obese. Birth outcomes and maternal morbidities were obtained from clinic cards after the births.

RESULTS

Pregnant women were recruited into the study (n = 1 058). Significant differences were found between the different gestational BMI categories and the following birth outcomes: maternal (p-value = 0.019), infant hospital stay (p-value = 0.03), infants staying for over 24 hours in hospital (p-value = 0.001), delivery mode (p-value = 0.001), birthweight (p-value = 0.006), birth length (p-value = 0.007), birth head circumference (p-value = 0.007) and pregnancy-induced hypertension (p-value = 0.001).

CONCLUSION

To the best of our knowledge, this is the first study that has used the gestational BMI method in a peri-urban South African pregnant population. Based on the findings that this method is able to identify unfavourable birth outcomes, it is recommended that it is implemented as a pilot study in selected rural, peri-urban and urban primary health clinics, and that its ease and effectiveness as a screening tool is evaluated. Appropriate medical and nutritional advice can then be given to pregnant women to improve both their own and their infants' birth-related outcomes and maternal morbidities.

Gestational diabetes screening with the new IADPSG guidelines: a cost-effectiveness analysis

OBJECTIVE

This study investigates the cost effectiveness of gestational diabetes mellitus screening using the new International Association of Diabetes in Pregnancy Study Group (IADPSG) guidelines.

STUDY DESIGN

A decision analytic model was built comparing routine screening with the 2-hour (2h) oral glucose tolerance test (OGTT) vs the 1-hour glucose challenge test. All probabilities, costs, and benefits were derived from the literature. Base case, sensitivity analyses, and a Monte Carlo simulation were performed.

RESULTS

Screening with the 2h OGTT was more expensive, more effective, and cost effective at $61,503/quality-adjusted life year. In a 1-way sensitivity analysis, the more inclusive IADPSG diagnostic approach remained cost effective as long as an additional 2.0% or more of patients were diagnosed and treated for gestational diabetes mellitus.

CONCLUSION

Screening at 24-28 weeks' gestational age under the new IADPSG guidelines with the 2h OGTT is expensive but cost effective in improving maternal and neonatal outcomes. How the health care system will provide expanded care to this group of women will need to be examined.

Fear of litigation and cesarean section rates

Both the rates of cesarean section and the rates and payouts from obstetrical malpractice suits have risen in past decades, albeit not always in tandem. A great deal of evidence suggests that physicians practice defensive medicine, and many obstetricians acknowledge that a more liberal recourse to cesarean section is one such behavior in which they sometimes engage. However the degree to which fear of litigation actually is a contributor to, or perhaps even a driver of, the rising cesarean section rate is not as clearly known. In this article I will discuss the research that has been performed that attempts to epidemiologically assess the link between lawsuits, malpractice premiums and cesarean section rates. I will also consider factors beyond dollars and cents (e.g., cognitive biases, changing risk tolerance of doctors and patients) that may lie at the base of the relationship. Finally I will offer a brief discussion of how professional ethics should inform the actions that physicians take in these difficult circumstances.

[Prediction, prevention and management of shoulder dystocia]

Shoulder dystocia is one of the most tragic, fatal and unexpected obstetrical events, which is mostly unpredictable and unpreventable. This clinical picture is defined as a delivery that requires additional obstetric maneuvers to release the shoulders after gentle downward traction has failed. Shoulder dystocia occurs when the fetal shoulder impacts on the maternal symphysis or sacral promontory. The incidence of shoulder dystocia is 0.2-0.6%. High perinatal mortality and morbidity is associated with the condition, even when it is managed appropriately. Obstetricians should be aware of the existing risk factors, but should always be alert to the possibility of shoulder dystocia in all labors. Maternal morbidity is also increased, particularly postpartum hemorrhage, rupture of the uterus, injury of the bladder, urethra and the bowels and fourth-degree perineal tears. Complications of the newborn include asphyxia, perinatal mortality, fracture of the clavicula and the humerus. Brachial plexus injuries are one of the most important fetal complications of shoulder dystocia, complicating 4-16% of such deliveries. The purpose of this article is to review the current evidence regarding the possible prediction, prevention and management of shoulder dystocia.

Can shoulder dystocia be reliably predicted?

AIMS

To evaluate factors reported to increase the risk of shoulder dystocia, and to evaluate their predictive value at a population level.

METHODS

The South Australian Pregnancy Outcome Unit's population database from 2005 to 2010 was accessed to determine the occurrence of shoulder dystocia in addition to reported risk factors, including age, parity, self-reported ethnicity, presence of diabetes and infant birth weight. Odds ratios (and 95% confidence interval) of shoulder dystocia was calculated for each risk factor, which were then incorporated into a logistic regression model. Test characteristics for each variable in predicting shoulder dystocia were calculated.

RESULTS

As a proportion of all births, the reported rate of shoulder dystocia increased significantly from 0.95% in 2005 to 1.38% in 2010 (P = 0.0002). Using a logistic regression model, induction of labour and infant birth weight greater than both 4000 and 4500 g were identified as significant independent predictors of shoulder dystocia. The value of risk factors alone and when incorporated into the logistic regression model was poorly predictive of the occurrence of shoulder dystocia.

CONCLUSIONS

While there are a number of factors associated with an increased risk of shoulder dystocia, none are of sufficient sensitivity or positive predictive value to allow their use clinically to reliably and accurately identify the occurrence of shoulder dystocia.

Reducing the risk of shoulder dystocia and associated brachial plexus injury

Despite persisting controversy over shoulder dystocia prediction, prevention, and injury causation, the authors find considerable evidence in recent research in the field to recommend additional guidelines beyond the current American College of Obstetricians and Gynecologists and Royal College of Obstetricians and Gynecologists guidelines to improve clinical practice in managing patients at risk for experiencing shoulder dystocia. In this article, the authors offer health care providers information, practical direction, and advice on how to limit shoulder dystocia risk and, more importantly, to reduce adverse outcome risk.

Treating mild gestational diabetes mellitus: a cost-effectiveness analysis

OBJECTIVE

This study investigated the cost-effectiveness of treating mild gestational diabetes mellitus (GDM).

STUDY DESIGN

A decision analytic model was built to compare treating vs not treating mild GDM. The primary outcome was the incremental cost per quality-adjusted life year (QALY). All probabilities, costs, and benefits were derived from the literature. Base case, sensitivity analyses, and a Monte Carlo simulation were performed.

RESULTS

Treating mild GDM was more expensive, more effective, and cost-effective at $20,412 per QALY. Treatment remained cost-effective when the incremental cost to treat GDM was less than $3555 or if treatment met at least 49% of its reported efficacy at the baseline cost to treat of $1786.

CONCLUSION

Treating mild GDM is cost-effective in terms of improving maternal and neonatal outcomes including decreased rates of preeclampsia, cesarean sections, macrosomia, shoulder dystocia, permanent and transient brachial plexus injury, neonatal hypoglycemia, neonatal hyperbilirubinemia, and neonatal intensive care unit admissions.

A comparison of obstetric maneuvers for the acute management of shoulder dystocia

OBJECTIVE

To assess the efficacy of obstetric maneuvers for resolving shoulder dystocia and the effect that these maneuvers have on neonatal injury when shoulder dystocia occurs.

METHODS

Using an electronic database encompassing 206,969 deliveries, we identified all women with a vertex fetus beyond 34 0/7 weeks of gestation who incurred a shoulder dystocia during the process of delivery. Women whose fetuses had a congenital anomaly and women with an antepartum stillbirth were excluded. Medical records of all cases were reviewed by trained abstractors. Cases involving neonatal injury (defined as brachial plexus injury, clavicular or humerus fracture, or hypoxic-ischemic encephalopathy or intrapartum neonatal death attributed to the shoulder dystocia) were compared with those without injury.

RESULTS

Among 132,098 women who delivered a term cephalic liveborn fetus vaginally, 2,018 incurred a shoulder dystocia (1.5%), and 101 (5.2%) of these incurred a neonatal injury. Delivery of the posterior shoulder was associated with the highest rate of delivery when compared with other maneuvers (84.4% compared with 24.3-72.0% for other maneuvers; P<.005 to P<.001) and similar rates of neonatal injury (8.4% compared with 6.1-14.0%; P=.23 to P=.7). The total number of maneuvers performed significantly correlated with the rate of neonatal injury (P<.001).

CONCLUSION

Delivery of the posterior shoulder should be considered following the McRoberts maneuver and suprapubic pressure in the management of shoulder dystocia. The need for additional maneuvers was associated with higher rates of neonatal injury.

Maternal outcome of gestational diabetes mellitus

OBJECTIVE

To estimate maternal outcome of treated or untreated gestational diabetes mellitus (GDM).

METHODS

French and English publications were searched using PubMed and the Cochrane library.

RESULTS

The diagnosis of GDM includes a high risk population for preeclampsia and Caesarean sections (EL3). The risks are positively correlated with the level of hyperglycaemia in a linear way (EL2). Intensive treatment of mild GDM compared with routine care reduces the risk of pregnancy-induced hypertension (preeclampsia, gestational hypertension). Moreover, it does not increase the risk of operative vaginal delivery, Caesarean section and postpartum haemorrhage (EL1). Being overweight, obesity and maternal hyperglycaemia are independent risk factors for preeclampsia (EL2). Their association with GDM increases the risk of preeclampsia and Caesarean section compared to diabetic women with a normal body mass index (EL3). The association of several risk factors (such as advanced maternal age, pre-existing chronic hypertension, pre-existing nephropathy, obesity, suboptimal glycaemic control) increases the risk of preeclampsia. In that case, the classic follow-up (blood pressure measurement, proteinuria) should be more frequent than monthly (professional consensus). The risk of Caesarean section is increased by macrosomia, whether suspected prenatally or not, but this increased risk remains whatever the birth weight (EL3). Diagnosis and treatment of GDM do not reduce the risk of severe perineal lesions, operative vaginal delivery and postpartum haemorrhage (EL2). Some psychological symptoms, such as anxiety and alteration of self-perception, can occur upon diagnosis of GDM (EL3). The treatment of GDM appears to reduce the risk of postpartum depression symptoms (EL2).

CONCLUSION

Most of the information published on GDM covers the risks of preeclampsia and Caesarean section; intensive care of GDM reduces these risks. Pregnancy care should be adjusted to the risk factors.

Shoulder Dystocia: Etiology, Common Risk Factors, and Management

Shoulder dystocia and brachial plexus injury occur in 0.5% to 1.5% of all births. Risk factors for both include maternal obesity, excessive prenatal weight gain, maternal diabetes, protracted labor, and fetal macrosomia. These factors are involved in only about 50% of births complicated by shoulder dystocia or brachial plexus injury. Shoulder dystocia has a low recurrence rate (9.8%-16.7%), although history of previous shoulder dystocia is the most reliable predictor of occurrence. Brachial plexus injury is the most common morbidity associated with shoulder dystocia, but 50% of newborns who present with this injury were not subject to shoulder dystocia at birth. Most brachial plexus injuries are transient, although 5% to 22% become permanent. Shoulder dystocia followed by permanent brachial plexus injury or mental impairment is one of the leading causes of malpractice allegations. Prompt assessment and management of shoulder dystocia and preparation to maximize the efficiency of shoulder dystocia maneuvers are critical. Documentation of the appropriate use of maneuvers to relieve shoulder dystocia demonstrates standard of care practice, thereby decreasing the potential for successful malpractice allegations.

Morbidade neonatal e maternas relacionada ao tipo de parto

Foi realizada uma análise da morbidade neonatal e materna e a mortalidade neonatal de acordo com o tipo de parto, cesariana ou vaginal. Foram estudadas prospectivamente 170 parturientes sem complicações gestacionais e com nascimento a termo: Grupo 1 (n = 95), puérpera com parto por via vaginal, Grupo 2 (n = 75), puérpera submetida à cesariana. Parâmetros maternos e fetais foram avaliados. Foi observada maior incidência de partos por via vaginal nas pacientes que estudaram até o ensino fundamental incompleto (p = 0,0045). Houve prevalência maior de partos prévios por via vaginal no Grupo 1 e de cesáreas no Grupo 2 (p < 0,001). Observou preferência de 78 (82,1%) das mulheres do Grupo 1 pelo parto vaginal contra apenas 28 (37,3%) das mulheres do Grupo 2, pela cesárea (p = 0,0002). Houve dor intensa no pós-operatório nas pacientes submetidas a parto cesáreo (oito casos) (p = 0,018). Traumas obstétricos foram verificados em catorze recém-nascidos do Grupo 1 e em sete do Grupo 2 (p = 0,28). Concluímos que existe maior morbidade neonatal em recém-natos de parto por via vaginal quando comparada com neonatos de cesárea e maior morbidade materna em puérperas com parto cesariana.

Shoulder dystocia and the next delivery: Outcomes and management

OBJECTIVE

To evaluate delivery mode management decisions and the rate of shoulder dystocia recurrence for women with a prior delivery complicated by shoulder dystocia.

STUDY DESIGN

We used a computerized perinatal database and ICD-9 codes to identify all vaginal deliveries complicated by shoulder dystocia from 1996 to 2001. Subsequent deliveries over the next three years were identified and reviewed for relevant clinical, obstetric, and delivery outcomes. Management including use of labor induction, labor augmentation, operative vaginal delivery, and delivery mode (elective cesarean section (CS) vs. trial of labor (TOL)) were reviewed. The recurrence rate of shoulder dystocia was calculated and the characteristics of these cases further described.

RESULTS

Over the initial 5-year study, there were 25 995 vaginal deliveries, 205 shoulder dystocia cases (0.8%), 36 (17.5%) with neonatal injury. Of the 205 initial shoulder dystocia cases, 39 patients had 48 subsequent deliveries at our institution (a subsequent delivery rate of 23% at our institution, significantly less than the overall population (42%, p < 0.001)). Complete data were available for 47 deliveries. Four women had elective CS without labor (one due to prior shoulder dystocia), 43 (91.5%) had a TOL, and 42 (88%) achieved vaginal delivery. Recurrent shoulder dystocia complicated 9.5% (4/42) of deliveries; one case included neonatal brachial plexus injury that resolved prior to hospital discharge. Of the four recurrent shoulder dystocia cases, none were complicated by maternal diabetes, macrosomia, prolonged second stage of labor, or underwent an operative vaginal delivery. No statistically significant univariate differences were seen between the recurrence group and the no-shoulder dystocia vaginal delivery group; however birth weight and nulliparity at initial shoulder dystocia pregnancy jointly demonstrated a relationship of recurrence (p = 0.048).

CONCLUSION

In TOL cases that result in a vaginal delivery, the rate of recurrence of shoulder dystocia is high--approximately 10 times higher than the rate for the general population. Often the only identifiable risk factor is the prior history itself, which may influence delivery management in subsequent pregnancies. Birth weight and nulliparity at initial shoulder dystocia pregnancy may influence clinical decision-making in cases of prior shoulder dystocia.

Shoulder dystocia in a Jamaican cohort

OBJECTIVE

To assess the risk factors for shoulder dystocia in Jamaica.

METHODS

A retrospective cohort analysis of all cases of shoulder dystocia, and birth weight-matched controls identified from January 1, 2000 to December 31, 2004. Multiple factors were analyzed individually and in combination to identify risk factors.

RESULTS

The incidence of shoulder dystocia was 0.83%. Nulliparity, a first stage of labor greater than 7 hours, a second stage lasting more than 1 hour, and use of oxytocin augmentation were found to be statistically significant factors with unadjusted odds ratios (95% confidence interval) of 1.78 (0.86-3.34), 1.89 (0.91-3.94), 2.78 (0.24-31.47), and 1.56 (0.77-3.15), respectively. The incidence of shoulder dystocia decreased as parity increased when adjusted for age.

CONCLUSION

Individual risk factors for shoulder dystocia remain obscure. The nulliparous pelvis, when controlled for neonatal weight, was associated with a statistically increased risk of shoulder dystocia; this risk decreased with increasing parity.

Gestational diabetes: diagnosis and management

PURPOSE

To review the diagnosis and management of gestational diabetes.

EPIDEMIOLOGY

In the United States, approximately 2 to 5% of all pregnant women have gestational diabetes. Those women with a family history of type 2 diabetes mellitus, Asian or native American race, Latina ethnicity or obesity are at higher risk for developing gestational diabetes.

CONCLUSION

Women with gestational diabetes who are treated appropriately can achieve good outcomes in the majority of pregnancies. Frequent blood glucose monitoring, nutrition counseling and frequent physician contact allow for individualized care to achieve optimal outcomes. Such treatment includes diet, exercise and insulin. The use of oral hypoglycemic agents is controversial and there is some concern about worse maternal and neonatal outcomes as compared to treatment with insulin. Evolving technologies promise to provide more therapeutic options.

Postdates and antenatal testing

The standard definition of a prolonged pregnancy is 42 completed weeks of gestation. The incidence of prolonged pregnancy varies depending on the criteria used to define gestational age at birth. It is estimated that 4 to 19% of pregnancies reach or exceed 42 weeks gestation. Several studies that have used very large computerized databases of well-dated pregnancies provided insights into the incidence and nature of adverse perinatal outcome such as an increased fetal and neonatal mortality as well as increased fetal and maternal morbidity in prolonged pregnancy. Fetal surveillance may be used in an attempt to observe the prolonged pregnancy while awaiting the onset of spontaneous labor. This article reviews the different methodologies and protocols for fetal surveillance in prolonged pregnancies. On the one hand, false-positive tests commonly lead to unnecessary interventions that are potentially hazardous to the gravida. On the other hand, to date, no program of fetal testing has been shown to completely eliminate the risk of stillbirth.

Obstetrical brachial plexus palsy

Obstetrical brachial plexus palsy, one of the most complex peripheral nerve injuries, presents as an injury during the neonatal period. The majority of the children recover with either no deficit or a minor functional deficit, but it is almost certain that some will not regain adequate limb function. These few cases must be managed in an optimal way. Considerable medical and legal debate has surrounded the etiologic factors of this traumatic lesion, and obstetricians are often considered responsible for the injury. According to recent studies, spontaneous endogenous forces may contribute substantially to this type of neonatal trauma. All obstetric circumstances that predispose to brachial plexus damage and that could be anticipated should be assessed. Correct diagnosis is necessary for the accurate estimation of prognosis and treatment. The most important aspect of therapy is timely recognition and referral, to prevent the various possible sequelae affecting the shoulder, elbow, or forearm. Since the early 1990s, research has increased the understanding of obstetrical brachial plexus palsy. Further research is needed, focused on developing strategies to predict brachial injury. This review focuses on emerging data relating to obstetrical brachial plexus palsy and discusses the present controversies regarding natural history, prognosis, and treatment in infants with brachial plexus birth palsies.

Suspected macrosomia? Better not tell

OBJECTIVE

To evaluate the management policy of delivery in a suspected macrosomic fetus and to describe the outcome of this policy.

STUDY DESIGN

For this prospective observational study we followed the management by reviewing the medical records of 145 women and their infants. The study population included women at term admitted to the obstetrics department with suspected macrosomic infants, as was diagnosed by an obstetrician and/or by fetal sonographic weight estimation of > or =4,000 g. The comparison group (n = 5,943) consisted of all women who gave birth during the data collection period.

RESULTS

Induction of labor and cesarean delivery rates in the macrosomic pregnancies (actual birth weight >4,000 g) of the study group were significantly higher when compared with the macrosomic pregnancies of the comparison group. When comparing the non-macrosomic to the macrosomic pregnancies (actual birth weight </>4,000 g) of the study group no significant difference was demonstrated regarding maternal or infant complications. The sensitivity, specificity and positive predictive value of the methods used for detecting macrosomia were 21.6, 98.6 and 43.5%, respectively.

CONCLUSION

Our ability to predict macrosomia is poor. Our management policy of suspected macrosomic pregnancies raises induction of labor and cesarean delivery rates without improving maternal or fetal outcome.

Obstetric management in gestational diabetes

Reviewing the areas of controversy related to the obstetric management of women with GDM, we are unfortunately unable to provide significant refinement of the recommendations agreed upon after the Fourth International Workshop-Conference due to the lack of properly controlled and powered clinical studies in this area since 1997. In the area of the need for antenatal fetal surveillance in women with milder degrees of GDM, we may be able to draw indirect conclusions from ongoing cohort studies that will include large numbers of women. In the area of optimal timing and mode of delivery to avoid fetal injury, large well-controlled prospective studies do not currently exist and are urgently needed. In addition, refinement of fetal and pelvic imaging techniques to more accurately identify the maternal-fetal pairs most likely to benefit from avoiding vaginal delivery, and the more widespread availability of these technologies, may also prove to be of benefit in the obstetric management of women with GDM.

Women with gestational diabetes mellitus in the ACHOIS trial: risk factors for shoulder dystocia

BACKGROUND

Gestational diabetes mellitus (GDM) is associated with increased risk of fetal macrosomia and shoulder dystocia. However, not all women with GDM and fetal macrosomia have shoulder dystocia.

AIMS

To identify the risk factors for shoulder dystocia in women with gestational diabetes using data from women recruited into the routine care group of the ACHOIS trial.

METHODS

A secondary analysis was performed on data collected from women enrolled in the ACHOIS trial. Bivariate analyses were performed using the Fisher exact test. Variables found to be significantly associated with shoulder dystocia and previously identified risk factors were used as explanatory variables in multivariate analyses.

RESULTS

A positive relationship was found between the severity of maternal fasting hyperglycaemia and the risk of shoulder dystocia, with a 1 mmol increase in fasting oral glucose-tolerance test leading to a relative risk (RR) of 2.09 (95% CI 1.03-4.25). Shoulder dystocia occurred more often in births requiring operative vaginal delivery (RR 9.58, 95% CI 3.70-24.81, P < 0.001). Macrosomic and large-for-gestational-age infants were more likely to have births complicated by shoulder dystocia (RR 6.27, 95% CI 2.33-16.88, P < 0.001 and RR 4.57, 95% CI 1.74-12.01, P < 0.005, respectively). Fetal macrosomia was the only variable to maintain its significance in all multivariate analyses.

CONCLUSIONS

Fetal macrosomia is the strongest independent risk factor for shoulder dystocia. Effective preventative strategies are needed.