Treatment of suspected fetal macrosomia: a cost-effectiveness analysis

Phytochemical composition, toxicological profiling and effect on pup birth weight of Corchorus olitorius leaf extract in rats: Implications for fetal macrosomia control

ETHNOPHARMACOLOGICAL RELEVANCE

Corchorus olitorius is used in ethnomedicine to arrest threatened miscarriage, ease labour, and promote smooth childbirth.

AIM OF THE STUDY

To evaluate the phytochemical composition, toxicity profile, and effect of Corchorus olitorius L. leaf extract (COLE) on fetal macrosomia control in rats.

MATERIALS AND METHODS

The chemical constituents of COLE were determined using gas chromatography-mass spectrometry (GC-MS). A single dose of up to 5000 mg/kg was administered in the acute toxicity test, and the rats were monitored for 14 days. In the sub-acute toxicity study, rats were treated with the extract for 28 days, and liver function, renal function, lipid profile, and serum antioxidant parameters, coupled with liver and kidney histology, were used to assess the toxicity potential of the extract. In the pup birth weight study, treatment of pregnant rats lasted until the birth of pups and continued for an extra 4 weeks. Rats in group 1 served as a control, whereas rats in groups 2, 3, and 4 received daily doses of 200, 400, and 800 mg/kg body weight of COLE, respectively, via oral gavage.

RESULTS

Bioactive compounds such as D-limonene, phytol, hexadecanoic acid, 9-octadecenoic acid (Z), dodecanoic acid, and ethyl 9,12,15-octadecatrienoate with well-known pharmacological activities were detected. LD50 of COLE was >5000 mg/kg. COLE decreased body weight and increased red blood cell, packed cell volume, and haemoglobin values when compared with the control (p < 0.05). COLE significantly decreased alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase but did not cause any significant (p > 0.05) changes in other biochemical (liver and kidney) parameters when compared to control. COLE decreased total cholesterol, triglycerides, low-density lipoprotein cholesterol, and increased high-density lipoprotein cholesterol when compared with the control (p < 0.05). Birth weights of pups were significantly decreased in the COLE-treated groups when compared with the control (p < 0.05), but the observed difference terminated by the fourth week of weaning.

CONCLUSION

The results showed that COLE is not toxic but has several bioactive compounds with known pharmacological activities and therefore may be a safe oral agent for fetal macrosomia control.

A model-based cost-utility analysis of multi-professional simulation training in obstetric emergencies

OBJECTIVE

To determine the cost-utility of a multi-professional simulation training programme for obstetric emergencies-Practical Obstetric Multi-Professional Training (PROMPT)-with a particular focus on its impact on permanent obstetric brachial plexus injuries (OBPIs).

DESIGN

A model-based cost-utility analysis.

SETTING

Maternity units in England.

POPULATION

Simulated cohorts of individuals affected by permanent OBPIs.

METHODS

A decision tree model was developed to estimate the cost-utility of adopting annual, PROMPT training (scenario 1a) or standalone shoulder dystocia training (scenario 1b) in all maternity units in England compared to current practice, where only a proportion of English units use the training programme (scenario 2). The time horizon was 30 years and the analysis was conducted from an English National Health Service (NHS) and Personal Social Services perspective. A probabilistic sensitivity analysis was performed to account for uncertainties in the model parameters.

MAIN OUTCOME MEASURES

Outcomes for the entire simulated period included the following: total costs for PROMPT or shoulder dystocia training (including costs of OBPIs), number of OBPIs averted, number of affected adult/parental/dyadic quality adjusted life years (QALYs) gained and the incremental cost per QALY gained.

RESULTS

Nationwide PROMPT or shoulder dystocia training conferred significant savings (in excess of £1 billion ($1.5 billion)) compared to current practice, resulting in cost-savings of at least £1 million ($1.5 million) per any type of QALY gained. The probabilistic sensitivity analysis demonstrated similar findings.

CONCLUSION

In this model, national implementation of multi-professional simulation training for obstetric emergencies (or standalone shoulder dystocia training) in England appeared to both be cost-saving when evaluating their impact on permanent OBPIs.

Neonatal brachial plexus palsy: associated birth injury outcomes, hospital length of stay and costs

OBJECTIVE

To compare the birth injury outcomes and hospital length of stay and costs among newborns delivered at 34-42 weeks with neonatal brachial plexus palsy (NBPP) versus those without.

STUDY DESIGN

We conducted a retrospective, cross-sectional study using data from the National Inpatient Sample to identify all newborns hospitalizations that occurred in the U.S. between 2016 and 2017. We included non-anomalous single liveborn delivered in-hospital at 34-42 weeks. The newborns with NBPP were identified by International Classification of Diseases, 10th Revision, Clinical Modification codes. Birth injury outcomes, and hospital length of stay and hospital costs were examined. A multivariable Poisson regression model with robust error variance was used to examine the association between NBPP and birth injury outcomes. A multivariable generalized linear regression model was used to examine the association between NBPP and hospital length of stay and hospital costs.

RESULTS

Of 7,019,722 non-anomalous single liveborn delivered at 34-42 weeks in the U.S. from 2016 to 2017, the rate of NBPP (n = 6695) was 0.95 per 1000 newborn hospitalizations. After multivariable regression adjustment, compared to newborns without NBPP, the risk of the composite birth injury outcome was 2.91 (95% CI 2.61-3.25) times higher in those with NBPP. Similar results of an increased risk among newborns with NBPP were observed in all individual birth injury outcomes. Compared to newborns without NBPP, after adjustment, the hospital length of stay was 1.48 (95% IC 1.38-1.59) times higher and the hospital costs were 2.21 (95% CI 1.97-2.48) times higher in those with NBPP.

CONCLUSIONS

Among newborns delivered at 34-42 weeks, the risk of associated birth injuries, hospital length of stay and costs, were significantly higher in newborns with NBPP than those without.

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.

Persistence and Extent of Neonatal Brachial Plexus Palsy: Association with Number of Maneuvers and Duration of Shoulder Dystocia

Objective  The main objective of this article is to determine if persistence of neonatal brachial plexus palsy (NBPP) following shoulder dystocia was associated with maneuvers used or duration of impacted shoulder. Study Design  Retrospective review of children with NBPP and documented shoulder dystocia. Student t -tests and chi-squared tests were used to compare outcomes when shoulder dystocia resolved with > 3 versus ≤ 3 maneuvers or duration > versus ≤ 120 seconds. Relative risk (RR) with 95% confidence intervals (CI) was calculated. Results  Among 46 children with NBPP and shoulder dystocia, incidence of persistence was significantly higher at 2 years of age when > 3 versus ≤ 3 maneuvers were used (100 vs. 62%; RR: 1.6, 95% CI: 1.2-2.2). When resolution of impacted shoulder lasted >120 versus ≤ 120 seconds, NBPP at 2 years was significantly more likely (100 vs. 63%; RR: 1.6, 95% CI: 1.1-2.2). Injury to all five nerves of the brachial plexus was more likely if standard deviation lasted > 120 versus ≤ 120 seconds (RR: 2.2; 95% CI: 1.03-4.6). Conclusion  Though the number of maneuvers used and duration of shoulder dystocia are associated with persistence of NBPP, the retrospective nature of the study of a selective cohort precludes recommendations changing the current management of shoulder dystocia.

Cost-effectiveness of simulation-based team training in obstetric emergencies (TOSTI study)

OBJECTIVE

Team training is frequently applied in obstetrics. We aimed to evaluate the cost-effectiveness of obstetric multi-professional team training in a medical simulation centre.

STUDY DESIGN

We performed a model-based cost-effectiveness analysis to evaluate four strategies for obstetric team training from a hospital perspective (no training, training without on-site repetition and training with 6 month or 3-6-9 month repetition). Data were retrieved from the TOSTI study, a randomised controlled trial evaluating team training in a medical simulation centre. We calculated the incremental cost-effectiveness ratio (ICER), which represent the costs to prevent the adverse outcome, here (1) the composite outcome of obstetric complications and (2) specifically neonatal trauma due to shoulder dystocia.

RESULTS

Mean costs of a one-day multi-professional team training in a medical simulation centre were €25,546 to train all personnel of one hospital. A single training in a medical simulation centre was less effective and more costly compared to strategies that included repetition training. Compared to no training, the ICERs to prevent a composite outcome of obstetric complications were €3432 for a single repetition training course on-site six months after the initial training and €5115 for a three monthly repetition training course on-site after the initial training during one year. When we considered neonatal trauma due to shoulder dystocia, a three monthly repetition training course on-site after the initial training had an ICER of €22,878.

CONCLUSION

Multi-professional team training in a medical simulation centre is cost-effective in a scenario where repetition training sessions are performed on-site.

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.

A multistate population-based analysis of linked maternal and neonatal discharge records to identify risk factors for neonatal brachial plexus injury

OBJECTIVE

To evaluate the interaction and contribution of maternal and fetal risk factors associated with neonatal brachial plexus injury (BPI).

METHODS

In a case-control study, matched maternal and neonatal discharge records were accessed from US State Inpatient Databases for New Jersey (2010-2012), Michigan (2010-2011), and Hawaii (2010-2011). Univariate and multivariate logistic regressions were used to evaluate associations between risk factors and BPI. Area under the receiver operating characteristic curve was used to build predictive models, including two stratified models evaluating deliveries among obese and diabetic cohorts.

RESULTS

Among 376 325 deliveries, BPI was diagnosed in 274 (0.1%). Significant BPI risk factors included maternal obesity (odds ratio [OR] 2.7, 95% confidence interval [CI] 1.7-4.4), maternal diabetes (OR 4.6, 95% CI 3.0-7.0), use of forceps (OR 4.6, 95% CI 2.3-9.0), and vacuum assistance (OR 2.3, 95% CI 1.7-3.3). After adjusting for shoulder dystocia and other predictive factors, cesarean reduced the risk of BPI by 88% (OR 0.1, 95% CI 0.07-0.2). When stratified by obesity and diabetes, the ORs for BPI increased significantly for macrosomia, forceps, and vacuum assistance.

CONCLUSION

The analysis confirms and quantifies more precisely the impact of risk factors for neonatal BPI, and provides a reliable basis for evidence-based clinical decision-making models.

The Suspected Macrosomic Fetus at Term: A Clinical Dilemma

Estimation of fetal weight is an important component of antenatal and intrapartum management of pregnant women. While many clinicians use ultrasound estimates of fetal weight to assess fetal growth, there are inherent challenges in both the diagnosis and management of suspected fetal macrosomia. Given the inaccuracy in estimating fetal weight, and the risks that accompany cesarean birth or induction of labor, the management of suspected fetal macrosomia requires open communication and shared decision making between the woman and her health care providers. This case study and literature review highlight the current management and recommendations for suspected fetal macrosomia.

Health economic modeling to assess short-term costs of maternal overweight, gestational diabetes, and related macrosomia - a pilot evaluation

Background: Despite the interest in the impact of overweight and obesity on public health, little is known about the social and economic impact of being born large for gestational age or macrosomic. Both conditions are related to maternal obesity and/or gestational diabetes mellitus (GDM) and associated with increased morbidity for mother and child in the perinatal period. Poorly controlled diabetes during pregnancy, pre- pregnancy maternal obesity and/or excessive maternal weight gain during pregnancy are associated with intermittent periods of fetal exposure to hyperglycemia and subsequent hyperinsulinemia, leading to increased birth weight (e.g., macrosomia), body adiposity, and glycogen storage in the liver. Macrosomia is associated with an increased risk of developing obesity and type 2 diabetes mellitus later in life.

Objective: Provide insight in the short-term health-economic impact of maternal overweight, GDM, and related macrosomia. To this end, a health economic framework was designed. This pilot study also aims to encourage further health technology assessments, based on country- and population-specific data.

Results: The estimation of the direct health-economic burden of maternal overweight, GDM and related macrosomia indicates that associated healthcare expenditures are substantial. The calculation of a budget impact of GDM, based on a conservative approach of our model, using USA costing data, indicates an annual cost of more than $1,8 billion without taking into account long-term consequences.

Conclusion: Although overweight and obesity are a recognized concern worldwide, less attention has been given to the health economic consequences of these conditions in women of child-bearing age and their offspring. The presented outcomes underline the need for preventive management strategies and public health interventions on life style, diet and physical activity. Also, the predisposition in people of Asian ethnicity to develop diabetes emphasizes the urgent need to collect more country-specific data on the incidence of macrosomic births and health outcomes. In addition, it would be of interest to further explore the long-term health economic consequences of macrosomia and related risk factors.

Mode of delivery and outcomes by birth weight among spontaneous and induced singleton cephalic nulliparous labors

OBJECTIVE

To assess the effect of birth weight on mode of delivery among nulliparous women in a setting with no policy of elective induction for suspected macrosomia.

METHODS

In an observational study, data were assessed from nulliparous women with a single cephalic pregnancy of at least 37 weeks in spontaneous (Robson group 1) and induced (Robson group 2a) labor attending a hospital in Dublin, Ireland, between January 1, 2008, and December 31, 2009. The primary outcome measure was mode of delivery.

RESULTS

A total of 7528 nulliparous labors were included (4989 in group 1 and 2539 in group 2a). The cesarean section rate was 15.1% overall (n=1139), with 411 (8.2%) in group 1, and 728 (28.7%) in group 2a. Cesarean delivery rates rose with increasing birth weight in group 1, from 119 (6.3%) of 1886 infants weighing 3000-3499 g and 160 (8.5%) of 1892 weighing 3500-3999 g, to 19 (26.8%) of 71 weighing 4500-4999 g. Rates of cesarean delivery were significantly higher in induced labor (group 2a) for each birth-weight category, ranging from 202 (25.9%) of 781 weighing 3000-3499 g and 243 (27.0%) of 899 weighing 3500-3999 g, to 38 (48.1%) of 79 weighing 4500-4999 g (P<0.01 for all).

CONCLUSION

In a setting with standardized management of labor, birth weight remains a significant determinant of mode of delivery.

Does induction of labor for constitutionally large-for-gestational-age fetuses identified in utero reduce maternal morbidity?

BACKGROUND

The number of infants with a birth weight > 97th percentile for gestational age has increased over the years. Although some studies have examined the interest of inducing labor for fetuses with macrosomia suspected in utero, only a few have analyzed this suspected macrosomia according to estimated weight at each gestational age. Most studies have focused principally on neonatal rather than on maternal (and still less on perineal) outcomes. The principal aim of this study was to assess whether a policy of induction of labor for women with a constitutionally large-for-gestational-age fetus might reduce the occurrence of severe perineal tears; the secondary aims of this work were to assess whether this policy would reduce either recourse to cesarean delivery during labor or neonatal complications.

METHODS

This historical cohort study (n = 3077) analyzed records from a French perinatal database. Women without diabetes and with a cephalic singleton term pregnancy were eligible for the study. We excluded medically indicated terminations of pregnancy and in utero fetal deaths. Among the pregnancies with fetuses suspected, before birth, of being large-for-gestational-age, we compared those for whom labor was induced from ≥ 37 weeks to ≤ 38 weeks+ 6 days (n = 199) to those with expectant obstetrical management (n = 2878). In this intention-to-treat analysis, results were expressed as crude and adjusted relative risks.

RESULTS

The mean birth weight was 4012 g ± 421 g. The rate of perineal lesions did not differ between the two groups in either primiparas (aRR: 1.06; 95% CI: 0.86-1.31) or multiparas (aRR: 0.94; 95% CI: 0.84-1.05). Similarly, neither the cesarean rate (aRR: 1.11; 95% CI: 0.82-1.50) nor the risks of resuscitation in the delivery room or of death in the delivery room or in the immediate postpartum or of neonatal transfer to the NICU (aRR = 0.94; 95% CI: 0.59-1.50) differed between the two groups.

CONCLUSIONS

A policy of induction of labor for women with a constitutionally large-for-gestational-age fetus among women without diabetes does not reduce maternal morbidity.

An overview of the health economic implications of elective caesarean section

The caesarean section rate has continued to increase in most industrialised countries, which raises a number of economic concerns. This review provides an overview of the health economic implications of elective caesarean section. It provides a succinct summary of the health consequences associated with elective caesarean section for both the infant and the mother over the perinatal period and beyond. It highlights factors that complicate our understanding of the health consequences of elective caesarean section, including inconsistencies in definitions and coding of the procedure, failure to adopt an intention-to-treat principle when drawing comparisons, and the widespread reliance on observational data. The paper then summarises the economic costs associated with elective caesarean section. Evidence is presented to suggest that planned caesarean section may be less costly than planned vaginal birth in some clinical contexts, for example where the singleton fetus lies in a breech position at term. In contrast, elective caesarean section (or caesarean section as a whole) appears to be more costly than vaginal delivery (either spontaneous or instrumented) in low-risk or unselected populations. The paper proceeds with an overview of economic evaluations associated with elective caesarean section. All are currently based on decision-analytic models. Evidence is presented to suggest that planned trial of labour (attempted vaginal birth) following a previous caesarean section appears to be a more cost-effective option than elective caesarean section, although its cost effectiveness is dependent upon the probability of successful vaginal delivery. There is conflicting evidence on the cost effectiveness of maternal request caesareans when compared with trial of labour. The paucity of evidence on the value pregnant women, clinicians and other groups in society place on the option of elective caesarean section is highlighted. Techniques that might be used to elicit preferences for elective caesarean section and its attributes are outlined. The review concludes with directions for future research in this area.

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.

Non-diabetic macrosomia: an obstetric dilemma

Fetal macrosomia represents a continuing challenge in obstetrics, as it has risk of shoulder dystocia leading to transient or permanent fetal, maternal injury and medicolegal liability. The overall incidence of macrosomia has been rising. Non-diabetic macrosomia is still an obstetric dilemma, as there is no clear consensus regarding its ante-partum prediction and management, as accurate diagnosis is only made retrospectively. The risk of shoulder dystocia rises from 1.4% for all vaginal deliveries to 9.2-24% for birth weights more than 4,500 g. Unfortunately, 50% of all cases of shoulder dystocia occur at birth weights of less than 4,000 g. Brachial plexus injury occurs in 1:1,000 births and permanent damage in 1:10,000 deliveries (12% of all) leading to litigation 1:45,000 deliveries. The prenatal diagnosis of macrosomia remains imprecise. Pre-pregnancy and ante-partum risk factors and ultrasound have poor predictive value. Induction of labour and prophylactic caesarean delivery has not been shown to alter the incidence of shoulder dystocia among nondiabetic patients. Caesarean section and induction of labour are associated with increased risk of operative morbidity and mortality with added cost implications.

Design of FitFor2 study: the effects of an exercise program on insulin sensitivity and plasma glucose levels in pregnant women at high risk for gestational diabetes

Background

Pregnancy is a period in the life of women that is often associated with decreased daily physical activity and/or exercise. However, maintaining adequate levels of daily physical activity during pregnancy is important for mother and child. Studies suggest that moderate daily physical activity and exercise during pregnancy are associated with reductions in the risk of gestational diabetes mellitus (GDM). However, at present, physical activity is not routinely advised to pregnant women at risk for gestational diabetes in the Netherlands. In FitFor2-study we aim to assess whether an exercise program can improve insulin sensitivity and fasting plasma glucose levels of women at high risk for gestational diabetes, assuming that this will lower their risk of gestational diabetes.

Methods

The FitFor2-study is a randomised controlled trial. Women who visit one of the participating hospitals or midwifery practices and who are at risk for gestational diabetes are eligible to participate. After baseline measurement they are randomly allocated to in the intervention or control group. The intervention group receives an exercise program twice a week in addition to usual care. The exercise program consist of aerobic and strength exercises and takes place under close supervision of a physiotherapist. Data are collected at 15, 24 and 32 weeks of pregnancy and 12 weeks after delivery. Primary maternal outcome measures are fasting plasma glucose and relative increase in insulin resistance. Primary neonatal outcome is birth weight. Secondary outcome measures are: maternal serum triglycerides, HDL, cholesterol, HbA1c, maternal weight gain during pregnancy, maternal physical activity level, foetal growth.

Discussion

If the FitFor2 intervention program proves to be effective, obstetricians and midwives should refer women at risk for GDM to a special exercise program. Exercise programs for pregnant women under supervision of an experienced trainer are already available in the Netherlands, and these programs could be adjusted easily for this target group. Furthermore, the costs of these programs should be refunded by including them in the basic health care cost reimbursement schemes.

Trial registration

NTR1139

The economics of elective cesarean section

Four million deliveries occur annually in the United States, and obstetric care has traditionally constituted a substantial portion of medical costs for young women, as well as being a major source of uncompensated care. The economic implications of a large shift in the mode of delivery are potentially important. This article reviews the relevant economic issues surrounding elective cesarean section and cesarean section at maternal request, summarizes the methodological quality and results of current literature on the topic, and presents recommendations for further study.

Neonatal morbidity and mortality after elective cesarean delivery

This article explores the effects of elective cesarean delivery (ECD) at term on neonatal morbidity and mortality. Available data have limitations, and do not provide conclusive evidence regarding the safety of planned ECD versus planned vaginal delivery. Some data suggest an association between ECD and increased neonatal respiratory morbidity and lacerations, and possibly decreased central and peripheral nervous system injury. Potentially increased risks of neonatal mortality with ECD at term may be counterbalanced by risks for fetal demise in ongoing pregnancies. Patients and physicians considering ECD should review competing risks and benefits; further research is needed to inform these discussions.

Gestational Diabetes: A Review of the Current Literature and Guidelines

Despite large numbers of original research studies spanning 4 decades there is still no consensus on the subject of gestational diabetes. Should all pregnant women be screened or only those with risk factors? Or is it safe not to screen at all? Which screening test and which diagnostic test are the most reliable? Which cutoff values should we use? What are the risks involved for mother and baby and can treatment improve outcome? What is the connection between gestational diabetes and diabetes mellitus type II? Are there disadvantages to screening? A review of relevant articles shows that definitive answers to these questions are not yet available. There is no gold standard screening test and no threshold glucose value above which complications are markedly increased. On the contrary, there appears to be a continuum of slowly increasing risks with rising blood glucose values, where it seems difficult to draw a clear line between pathology and physiology. Moreover, treatment has thus far not been shown to significantly improve outcome. There seems to be an indistinct area between the diagnosis of gestational diabetes and diabetes mellitus type II, where women with risk factors for one are also predisposed to develop the other, thereby confusing the diagnosis. Finally, the disadvantages to diagnosing and treating women without a clearly proven benefit seem to be significant. Therefore it seems defensible to suspend all screening and treatment for gestational diabetes, or at least significantly raise the threshold for making a positive diagnosis and initiating treatment, until further research has proven a clear benefit.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader should be able to summarize that there is still no worldwide consensus on the diagnosis, management, and adverse effects of Gestational Diabetes Mellitus (GDM); explain that all methods of screening vary in sensitivity and depend on very strict preparations for screening; state that there is no agreement on ideal levels of blood glucose to prevent untoward effects; and recall that there are two very large prospective studies that clarify the dark waters and that we should await their results.

Cesarean section on request at 39 weeks: impact on shoulder dystocia, fetal trauma, neonatal encephalopathy, and intrauterine fetal demise

PURPOSE

The purpose of this analysis was to determine the impact on specific forms of neonatal morbidity and mortality by allowing women to opt for delivery by elective cesarean section at 39 weeks of gestation (EGA). According to the National Vital Statistics Reports, over 70% of deliveries in the U.S. annually are at gestational ages>or=39 weeks EGA. Estimating that over 4 million deliveries occur annually in the United States, this would yield approximately 3 million pregnancies wherein the woman may exercise her choice for either primary or repeat cesarean section at 39 weeks EGA or at the point when labor is established.

METHODS

A search was conducted using Ovid Medline spanning the past 10 years using the following key words: fetal trauma, shoulder dystocia, brachial plexus palsy, neonatal skull fracture, obstetrical trauma, traumatic delivery, intrauterine fetal demise, stillbirth, fetal demise, and neonatal encephalopathy. Using this search technique, over 2100 articles were identified. The abstracts were reviewed and pertinent articles were chosen for further consideration. The identified articles and their applicable references were obtained for inclusion in this review. Preference was given to publications on or after the year 2000 with the exception of classical or sentinel articles, which were included without regard to year of publication.

RESULTS

Four major categories of neonatal morbidity and mortality are discussed: Shoulder dystocia: Accepting that we do not have a successful method for the prediction or prevention of shoulder dystocia, the question becomes, "What is the chance that a baby will sustain a permanent brachial plexus injury at delivery?" Additionally, is there a significant protective effect of cesarean section in reducing the risk of such injury? Currently, the occurrence rate of brachial plexus palsy at the time of vaginal delivery ranges from 0.047% to 0.6% and for cesarean section from 0.0042% to 0.095%. Using a composite estimate of the risk of 0.15% for vaginal deliveries and applying it to the 3 million deliveries>or=39 weeks EGA, approximately 4500 cases of brachial plexus palsy would occur. If only 15% of these injuries were permanent, 675 permanent brachial plexus palsies would occur annually. If the risk of permanent injury is 1 in 10,000 as reported by Chauhan, 300 permanent brachial plexus palsies would occur annually in the United States. The range then for permanent brachial plexus injury that could be avoided with cesarean section on request would appear to vary between 1 in 5000 and 1 in 10,000 vaginal births. Fetal trauma: The incidence of significant birth trauma varies from 0.2 to 1 to 2 per 1000 births. The use of sequential instruments, for example, vacuum followed by forceps or vice versa, is specifically associated with an unacceptably high injury rate. Intrapartum-related neonatal deaths of vertex singleton fetuses with birthweights>2500 g from traumatic cranial or cervical spine injury secondary to vacuum- or forceps-assisted vaginal delivery are still occurring. Overall, the frequency of significant fetal injury is significantly greater with vaginal delivery, especially operative vaginal delivery, than with cesarean section for the nonlaboring woman at 39 weeks EGA or near term when early labor has been established. Neonatal encephalopathy: The prevalence of moderate to severe neonatal encephalopathy is 3.8/1000 term live births with a neonatal fatality rate of 9.1%. In 4% to 10% of cases, the etiology appears to be pure intrapartum hypoxia. Intrapartum hypoxia superimposed on antepartum risk factors may account for up to 25% of the moderate to severe encephalopathies, according to one cohort. A paradox in the data thus far is that infants born to nonlaboring women delivered by cesarean section had an 83% reduction in the occurrence of moderate or severe encephalopathy. Considering a prevalence of moderate or severe neonatal encephalopathy of 0.38% and applying it to the 3 million deliveries occurring at >or=39 weeks EGA in the United States annually, 11,400 cases of moderate to severe encephalopathy would occur. The rate of encephalopathy observed in infants delivered by cesarean section would yield approximately 1938 cases. This net difference in moderate to severe encephalopathy would represent 9462 cases annually in the United States that could be prevented with elective cesarean section. Although cesarean delivery may be protective for the development of neonatal encephalopathy, to date it has not proven to be protective of long-term neurologic injury in the form of cerebral palsy with or without mental retardation and/or seizure disorders. Intrauterine fetal demise: Copper reported that the rate of stillbirth is consistent from 23 to 40 weeks EGA with about 5% of all stillbirths occurring at each week of gestation. Yudkin reported a rate of 0.6 stillbirths per 1000 live births from 33 to 39 weeks EGA. After 39 weeks EGA, a significant increase in the stillbirth rate was reported (1.9 per 1000 live births). Fretts reported on fetal deaths per 1000 live births from 37 to 41 weeks of gestational age, showing that the rate progressively increased from 1.3 to 4.6 with each week of gestation. It can be estimated that delivery at 39 weeks EGA would prevent 2 fetal deaths per 1000 living fetuses. This would translate into the prevention of as many as 6000 intrauterine fetal demises in the United States annually-an impact that far exceeds any other strategy implemented for stillbirth reduction thus far.

CONCLUSION

It is reasonable to inform the pregnant woman of the risk of each of the above categories, in addition to counseling her regarding the potential risks of a cesarean section for the current and any subsequent pregnancies. The clinician's role should be to provide the best evidence-based counseling possible to the pregnant woman and to respect her autonomy and decision-making capabilities when considering route of delivery.