Guideline No. 392-Pregnancy and Maternal Obesity Part 2: Team Planning for Delivery and Postpartum Care

Appraisal of clinical practice guidelines and consensus statements on obstetric anaesthesia: a systematic review using the AGREE II instrument

OBJECTIVES

Despite the publication of hundreds of trials on obstetric anaesthesia, the management of these conditions remains suboptimal. We aimed to assess the quality and consistency of guidance documents for obstetric anaesthesia.

DESIGN

This is a systematic review and quality assessment using the Appraisal of Guidelines for Research and Evaluation (AGREE) II methodology.

DATA SOURCES

Data sources include PubMed and Embase (8 June 2023), three Chinese academic databases, six guideline databases (7 June 2023) and Google and Google scholar (1 August 2023).

ELIGIBILITY CRITERIA

We included the latest version of international and national/regional clinical practice guidelines and consensus statements for the anaesthetic management of pregnant patients during labour, non-operative delivery, operative delivery and selected aspects of perioperative monitoring, postpartum care and analgesia, published in English or Chinese.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently screened the searched items and extracted data. Four reviewers independently scored documents using AGREE II. Recommendations from all documents were tabulated and visualised in a coloured grid.

RESULTS

Twenty-two guidance documents (14 clinical practice guidelines and 8 consensus statements) were included. Included documents performed well in the domains of scope and purpose (median 76.4%, IQR 69.4%-79.2%) and clarity of presentation (median 72.2%, IQR 61.1%-80.6%), but were unsatisfactory in applicability (median 21.9%, IQR 13.5%-27.1%) and editorial independence (median 47.9%, IQR 6.3%-73.2%). The majority of obstetric anaesthesia guidelines or consensus centred on different topics. Less than 30% of them specifically addressed the management of obstetric anaesthesia perioperatively. Recommendations were concordant on the perioperative preparation, and on some indications for the choice of anaesthesia method. Substantially different recommendations were provided for some items, especially for preoperative blood type and screen, and for the types and doses of neuraxial administration.

CONCLUSIONS

The methodological quality in guidance documents for obstetric anaesthesia necessitates enhancement. Despite numerous trials in this area, evidence gaps persist for specific clinical queries in this field. One potential approach to mitigate these challenges involves the endorsement of standardised guidance development methods and the synthesis of robust clinical evidence, aimed at diminishing difference in recommendations.

Clinical practice guidelines for the management of overweight and obesity published internationally: A scoping review

With the increasing prevalence of obesity placing additional demands on healthcare systems, many jurisdictions and professional bodies have developed clinical practice guidelines to support practitioners in the management of people with overweight and obesity. This scoping review aimed to identify key features of contemporary guidelines for the clinical management of overweight and obesity. Searches of MEDLINE, Guidelines International Network's international guidelines library, and other grey literature sources identified 38 guidelines of 18 countries and one region published since 2010. Guidelines were developed by committees (n = 36, 95%) that comprised knowledgeable experts (n = 36, 95%) and were multidisciplinary (n = 33, 87%), with limited consumer representation (n = 11, 29%). Guideline documentation incorporated review questions (n = 23, 61%), systematic reviews (n = 25, 66%), evidence grading systems (n = 33, 87%), processes for reaching consensus (n = 19, 50%), and guideline review details (n = 28, 74%). Treatment approaches included in most guidelines were nutrition and physical activity (n = 38, 100%), psychology (n = 37, 97%), pharmacotherapy (n = 32, 84%), and bariatric surgery (n = 31, 82%). Most guidelines targeted populations based on age (n = 30, 79%). Guidelines contained recommendations for pregnancy (n = 12, 32%), older adults (n = 9, 24%), and people with eating disorders (n = 8, 21%). Future guidelines would benefit from involvement of consumers including groups known to be at increased risk of overweight and obesity, targeted guidance for at risk groups, and consideration of weight bias and stigma.

The German guideline "Obesity in pregnancy": comparison with the international approach

BACKGROUND

Obesity is an increasing problem, even in young women of reproductive age. Obesity has a negative impact on conception, the course of pregnancy, and neonatal outcomes. Caring for obese pregnant women has becoming an important aspect of standard prenatal care. The Guideline "Obesity and Pregnancy" of the German Society of Gynecology and Obstetrics aims to create evidence-based recommendations which can be used to improve the care of obese pregnant women. As obesity is a worldwide problem, many societies for obstetrics and gynecology have created national guidelines.

METHODS

We reviewed the following guidelines for obesity and pregnancy: American College of Obstetricians and Gynecologists (ACOG) 2021, Royal College of Obstetrics and Gynecology (RCOG) 2018; AND Society of Obstetricians and Gynecologists of Canada (SOGC) 2019. These guidelines were compared to the German guideline.

RESULTS

There are some variations between the guidelines, though no major contradictions exist. Disparities were found regarding the recommendations for substitution of high folic acid and Vitamin D. Furthermore, the recommended time for screening for gestational diabetes and the methods to control fetal growth differ between the guidelines. Regarding place of birth, RCOG allows delivery in midwifery-led units in the absence of other high-risk circumstances, while others request facility of care by neonatologists and medical staff trained in care of obese women. Induction of labor at term due to increased risk of intrauterine demise is mostly limited to women with a body mass index of 40 kg/m2. Only one guideline considers induction of all obese women. For intrapartum management, the majority allows tolerating of longer labor times to delivery if fetal monitoring is sufficient and fetal stress is excluded. Special encouragement of breastfeeding and healthy lifestyle is commonly recommended; only in the Canadian guideline, postpartum depression evaluation is requested due to the overall high prevalence of depression and anxiety in obese women.

CONCLUSION

All guidelines consider pregnancies in obese women as high-risk pregnancies and emphasize the need for preconception counseling. There are special needs in pregnancy care and in the intrapartum and postpartum management to be observed.

Guideline No. 441: Antenatal Fetal Health Surveillance

OBJECTIVE

To summarize the current evidence and to make recommendations for antenatal fetal health surveillance (FHS) to detect perinatal risk factors and potential fetal decompensation in the antenatal period and to allow for timely intervention to prevent perinatal morbidity and/or mortality.

TARGET POPULATION

Pregnant individuals with or without maternal, fetal, or pregnancy-associated perinatal risk factors for antenatal fetal decompensation.

OPTIONS

To use basic and/or advanced antenatal testing modalities, based on risk factors for potential fetal decompensation.

OUTCOMES

Early identification of potential fetal decompensation allows for interventions that may support fetal adaptation to maintain well-being or expedite delivery.

BENEFITS, HARMS, AND COSTS

Antenatal FHS in pregnant individuals with identified perinatal risk factors may reduce the chance of adverse outcomes. Given the high false-positive rate, FHS may increase unnecessary interventions, which may result in harm, including parental anxiety, premature or operative birth, and increased use of health care resources. Optimization of surveillance protocols based on evidence-informed practice may improve perinatal outcomes and reduce harm.

EVIDENCE

Medline, PubMed, Embase, and the Cochrane Library were searched from inception to January 2022, using medical subject headings (MeSH) and key words related to pregnancy, fetal monitoring, fetal movement, stillbirth, pregnancy complications, and fetal sonography. This document represents an abstraction of the evidence rather than a methodological review.

VALIDATION METHODS

The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and weak recommendations).

INTENDED AUDIENCE

All health care team members who provide care for or education to obstetrical patients, including maternal fetal medicine specialists, obstetricians, family physicians, midwives, nurses, nurse practitioners, and radiologists.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Directive clinique no 441 : Surveillance prénatale du bien-être fœtal

OBJECTIF

Résumer les données probantes actuelles et formuler des recommandations pour la surveillance prénatale du bien-être fœtal afin de détecter les facteurs de risque périnatal et toute potentielle décompensation fœtale et de permettre une intervention rapide en prévention de la morbidité et la mortalité périnatales.

POPULATION CIBLE

Personnes enceintes avec ou sans facteurs maternels, fœtaux ou gravidiques associés à des risques périnataux et à la décompensation fœtale.

OPTIONS

Utiliser des examens prénataux par technologie de base et/ou avancée en fonction des facteurs de risque de décompensation fœtale. RéSULTATS: La reconnaissance précoce de toute décompensation fœtale potentielle permet d'intervenir de façon à favoriser l'adaptation fœtale pour maintenir le bien-être ou à accélérer l'accouchement. BéNéFICES, RISQUES ET COûTS: Chez les personnes enceintes ayant des facteurs de risque périnatal confirmés, la surveillance du bien-être fœtal contribue à réduire le risque d'issue défavorable. Compte tenu du taux élevé de faux positifs, la surveillance du bien-être fœtal peut augmenter le risque d'interventions inutiles, ce qui peut avoir des effets nuisibles, dont l'anxiété parentale, l'accouchement prématuré ou assisté et l'utilisation accrue des ressources de soins de santé. L'optimisation des protocoles de surveillance d'après des pratiques fondées sur des données probantes peut améliorer les issues périnatales et réduire les effets nuisibles. DONNéES PROBANTES: Des recherches ont été effectuées dans les bases de données Medline, PubMed, Embase et Cochrane Library, de leur création jusqu'à janvier 2022, à partir de termes MeSH et de mots clés liés à la grossesse, à la surveillance fœtale, aux mouvements fœtaux, à la mortinaissance, aux complications de grossesse et à l'échographie fœtale. Le présent document est un résumé des données probantes et non pas une revue méthodologique. MéTHODES DE VALIDATION: Les auteurs ont évalué la qualité des données probantes et la force des recommandations en utilisant le cadre méthodologique GRADE (Grading of Recommendations Assessment, Development and Evaluation). Voir l'annexe A en ligne (tableau A1 pour les définitions et tableau A2 pour l'interprétation des recommandations fortes et faibles). PROFESSIONNELS CONCERNéS: Tous les membres de l'équipe de soins qui prodiguent des soins ou donnent de l'information aux patientes en obstétrique, notamment les spécialistes en médecine fœto-maternelle, les obstétriciens, les médecins de famille, les sages-femmes, les infirmières, les infirmières praticiennes et les radiologistes. DÉCLARATIONS SOMMAIRES: RECOMMANDATIONS.

Impact of Obesity and Diabetes in Pregnant Women on Their Immunity and Vaccination

Pregnant women with obesity and diabetes are at increased risk of developing infections and other complications during pregnancy. Several mechanisms are involved in the immunological mechanisms that contribute to reduced immunity in these populations. Both obesity and diabetes are associated with chronic low-grade inflammation that can lead to an overactive immune response. Pregnant women with obesity and diabetes often have an increase in pro-inflammatory cytokines and adipokines, such as TNF-α, IL-6, IL-1β, leptin, and resistin, which are involved in the inflammatory response. Insulin resistance can also affect the functioning of immune cells. Furthermore, both conditions alter the composition of the gut microbiome, which produces a variety of biomolecules, including short-chain fatty acids, lipopolysaccharides, and other metabolites. These substances may contribute to immune dysfunction. In addition to increasing the risk of infections, obesity and diabetes can also affect the efficacy of vaccinations in pregnant women. Pregnant women with obesity and diabetes are at increased risk of developing severe illness and complications from COVID-19, but COVID-19 vaccination may help protect them and their fetuses from infection and its associated risks. Since both obesity and diabetes classify a pregnancy as high risk, it is important to elucidate the impact of these diseases on immunity and vaccination during pregnancy. Research examining the efficacy of the COVID-19 vaccine in a high-risk pregnant population should be of particular value to obstetricians whose patients are hesitant to vaccinate during pregnancy. Further research is needed to better understand these mechanisms and to develop effective interventions to improve immune function in these populations.

Clinical analysis of diabetes in pregnancy with stillbirth

We analyzed the clinical characteristics of patients with diabetes in pregnancy (DIP) associated with stillbirth and explored strategies to reduce its incidence. We retrospectively analyzed 71 stillbirths associated with DIP (group A) and 150 normal pregnancies (group B) during 2009 to 2018. The incidence of the following was higher in group A (P < .05): hypertensive disorders (38.03% vs 6.00%), placenta previa (14.08% vs 2.67%), placental abruption (5.63% vs 0.67%), fetal malformation (8.45% vs 0.67%), fasting plasma glucose (FPG) ≥ 7.0 mmol/L (46.48% vs 0.67%), 2-h postprandial plasma glucose ≥ 11.1 mmol/L (57.75% vs 6.00%), HbA1c ≥ 6.5% (63.38% vs 6.00%), and polyhydramnios (11.27% vs 4.67). The incidence of oligohydramnios (4.23% vs 6.67%) was lower in group A than in group B (P < .05). According to the gestational age at the time of stillbirth, Group-A cases were subgrouped into miscarriages (20-27+6 weeks), premature deliveries (28-36+6 weeks), and full-term deliveries (≥37 weeks). Age, parity, and DIP type did not differ among the subgroups (P > .05). Among patients with DIP, antenatal FPG, 2-h postprandial plasma glucose, and HbA1c were significantly associated with stillbirth (P < .05). Stillbirth was first detected at 22 weeks and typically occurred at 28-36+6 weeks. DIP was associated with a higher incidence of stillbirth, and FPG, 2-h postprandial plasma glucose, and HbA1c were potential indicators of stillbirth in DIP. Age (odds ratio [OR]: 2.21, 95% confidence interval [CI]: 1.67-2.74), gestational hypertension (OR: 3.44, 95% CI: 2.21-4.67), body mass index (OR: 2.86, 95% CI: 1.95-3.76), preeclampsia (OR: 2.29, 95% CI: 1.45-3.12), and diabetic ketoacidosis (OR: 3.99, 95% CI: 1.22-6.76) were positively correlated with the occurrence of stillbirth in DIP. Controlling perinatal plasma glucose, accurately detecting and managing comorbidities/complications, and timely termination of pregnancy can reduce the incidence of stillbirths associated with DIP.

Obesity in Pregnancy: A Comprehensive Review of Influential Guidelines

Importance

Obesity is one of the most common clinical entities complicating pregnancies and is associated with short- and long-term consequences for both the mother and the offspring.

Objective

The aim of this study were to review and compare the most recently published influential guidelines on the management of maternal obesity in the preconceptional, antenatal, intrapartum, and postpartum period.

Evidence Acquisition

A descriptive review of guidelines from the American College of Obstetricians and Gynecologists, the International Federation of Gynecology and Obstetrics, the Society of Obstetricians and Gynecologists of Canada, the Royal College of Obstetricians and Gynecologists, and the Royal Australian and New Zealand College of Obstetricians and Gynecologists on obesity in pregnancy was carried out.

Results

There is an overall agreement among the reviewed guidelines regarding the importance of prepregnancy weight loss with behavioral modification, optimization of gestational weight gain, and screening for comorbidities in improving pregnancy outcomes of obese women. Women with previous bariatric surgery should be screened for nutritional deficiencies and have a closer antenatal surveillance, according to all guidelines. In addition, folic acid supplementation is recommended for 1 to 3 months before conception and during the first trimester, but several discrepancies were identified with regard to other vitamins, iodine, calcium, and iron supplementation. All medical societies recommend early screening for gestational diabetes mellitus and early anesthetic assessment in obese women and suggest the use of aspirin for the prevention of preeclampsia when additional risk factors are present, although the optimal dosage is controversial. The International Federation of Gynecology and Obstetrics, Society of Obstetricians and Gynecologists of Canada, Royal College of Obstetricians and Gynecologists, and Royal Australian and New Zealand College of Obstetricians and Gynecologists point out that specific equipment and adequate resources must be readily available in all health care facilities managing obese pregnant women. Moreover, thromboprophylaxis and prophylactic antibiotics are indicated in case of cesarean delivery, and intrapartum fetal monitoring is justified during active labor in obese patients. However, there are no consistent protocols regarding the fetal surveillance, the monitoring of multiple gestations, the timing and mode of delivery, and the postpartum follow-up, although weight loss and breastfeeding are unanimously supported.

Conclusions

Obesity in pregnancy is a significant contributor to maternal and perinatal morbidity with a constantly rising global prevalence among reproductive-aged women. Thus, the development of uniform international protocols for the effective management of obese women is of paramount importance to safely guide clinical practice and subsequently improve pregnancy outcomes.

Quality Appraisal of Nutritional Guidelines to Prevent, Diagnose, and Treat Malnutrition in All Its Forms during Pregnancy

This work aimed to identify clinical practice guidelines (CPGs) that include recommendations for the prevention, diagnosis, and treatment of women’s malnutrition during pregnancy and to evaluate the quality of these guidelines using the Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument. We conducted a literature review using PubMed and different websites from January 2009 to February 2021. The quality of the CPGs was independently assessed by reviewers using the AGREE II instrument, which defines guidelines scoring >70% in the overall assessment as “high quality”. The analysis included 43 guidelines. Among the main findings, we identified that only half of the CPGs (51.1%) obtained a final “high quality” evaluation. AGREE II results varied widely across domains and categories. The two domains that obtained the highest scores were scope and purpose with 88.3% (range 39 to 100%) and clarity of presentation with 87.2% (range 25 to 100%). Among the “high quality” CPGs, the best scores were achieved by the three guidelines published by the National Institute of Health and Care Excellence (NICE) and the World Health Organization (WHO). Due to the importance of maternal nutrition in pregnancy, it is essential to join forces to improve the quality of the guidelines, especially in CPGs that do not meet the reference standards for quality.

Peripartum care of persons with obesity: a scoping review of recommendations and practical tools for implementation

OBJECTIVE

Despite the growing prevalence of obesity among reproductive aged persons in the USA, evidence-based guidelines for peripartum care are lacking. The objective of this scoping review is to identify obesity-related recommendations for peripartum care, evaluate grades of evidence for each recommendation, and identify practical tools (eg, checklists, toolkits, care pathways and bundles) to support their implementation in clinical practice.

DATA SOURCES

We searched MEDLINE, EMBASE, CINAHL, the Cochrane Central Register of Controlled Trials and ClinicalTrials.gov from inception to December 2020 for eligible studies addressing peripartum care in persons with obesity.

STUDY ELIGIBILITY CRITERIA

Inclusion criteria were published evidence-rated recommendations and practical tools for peripartum care of persons with obesity.

STUDY APPRAISAL AND SYNTHESIS METHODS

Pairs of independent reviewers extracted data (source, publication year, content and number of recommendations, level and grade of evidence, description of tool) and identified similarities and differences among the articles.

RESULTS

Of 18 315 screened articles, 18 were included including 7 articles with evidence-rated recommendations and 11 practical tools (3 checklists, 3 guidelines, 1 care bundle, 1 flowchart, 1 care pathway, 1 care map and 1 protocol). Thirteen of 39 evidence-rated recommendations were based on expert opinion. Recommendations related to surgical antibiotic prophylaxis and subcutaneous tissue closure at caesarean delivery received the highest grade of evidence. Some of the practical tools included a checklist from the USA regarding anticoagulation after caesarean delivery (evidence-supported recommendation), a bundle for surgical site infections after caesarean delivery in Australia (evidence did not support recommendation) and a checklist with content for several aspects of peripartum care from Canada (evidence supported seven of nine definitive recommendations).

CONCLUSION

The recommendations for peripartum care for persons with obesity are based on limited evidence and few practical tools for implementation exist. Future work should focus on developing practical tools based on high-quality studies.

Association between maternal adiposity measures and adverse maternal outcomes of pregnancy: Systematic review and meta-analysis

Maternal obesity increases pregnancy-related risks. Women with a body mass index (BMI) ≥ 30 kg/m² are considered to be at risk and should receive additional care, although approximately half will have uncomplicated pregnancies. This systematic review aimed to identify early pregnancy measures of adiposity associated with adverse maternal health outcomes. Searches included six databases, reference lists, citations, and contacting authors. Screening and quality assessment were carried out by two authors independently. Random effects meta-analysis and narrative synthesis were conducted. Seventy studies were included with a pooled sample of 89,588 women. Meta-analysis showed significantly increased odds of gestational diabetes mellitus (GDM) with higher waist circumference (WC) categories (1.40, 95% confidence interval [CI] 1.04, 1.88) and per unit increase in WC (1.31, 95% CI 1.03, 1.67). Women with GDM had higher WC than controls (mean difference [MD] 6.18 cm, 95% CI 3.92, 8.44). WC was significantly associated with hypertensive disorders, delivery-related outcomes, metabolic syndrome, and composite pregnancy outcomes. Waist to hip ratio was significantly associated with GDM, hypertensive disorders, and delivery-related outcomes. Fat mass, neck circumference, skinfolds, and visceral fat were significantly associated with adverse outcomes, although limited data were available. Our findings identify the need to explore how useful adiposity measures are at predicting risk in pregnancy, compared with BMI, to direct care to women with the greatest need.

Midwives perceptions of managing pregnancies complicated by obesity: A mixed methods study

OBJECTIVE

The growing prevalence of obesity is a concern for midwives. In Canada, the absence of regulatory standards, varying protocols and consultant preferences shape clinical decision making for the midwife and may lead to inconsistent practice. Our aim was to understand the barriers, enablers, and knowledge gaps that influenced experiences of midwives in Ontario, Canada when providing care to clients impacted by obesity.

METHODS

Mixed methods design using a sequential, explanatory approach. Surveys conducted with midwives were administered using an online platform, followed by semi-structured interviews to understand the perspectives elicited in the survey in greater detail. Interviews were audio recorded and transcribed verbatim. Survey data were analyzed using descriptive statistics, and thematic analysis was used for generating codes, categories and themes from the interview data.

RESULTS

144 midwives completed the survey and 20 participated in an interview. The participants described their clinical management when caring for those with obesity which included considerations regarding additional tests/investigations, consultation and transfer of care, and place of birth. Up to 93% of surveyed midwives believed that clients with obesity were appropriate for midwifery-led care however there was less certainty about suitability as BMI increased to higher ranges such as > 45). The care management was influenced by beliefs and attitudes, knowledge, and system-level factors. Midwives experienced barriers such as inconsistent practices and role confusion, and felt ill equipped to care for pregnancies affected by obesity due to unclear guidelines.

CONCLUSIONS

Overall, midwives believe clients with obesity are suitable for midwifery-led care due to its individualized, non-judgmental approach to care. Additional training for midwives and other obstetric care providers would be beneficial to help overcome barriers in providing effective care to pregnancies affected by obesity.

Weight management across preconception, pregnancy, and postpartum: A systematic review and quality appraisal of international clinical practice guidelines

This systematic review and quality appraisal evaluated clinical practice guidelines (CPGs) for weight management and weight-related behaviors across preconception, pregnancy, and postpartum. CPGs published in English were identified from research and guideline-specific databases between 2010 and 2019. Recommendations were categorized into weight (body mass index screening, weight loss, weight gain prevention, and gestational weight gain), diet, food safety, physical activity, and behavioral strategies. Three independent appraisers assessed CPG quality using the Appraisal of Guidelines Research and Evaluation II instrument. Twenty-two CPGs were included across preconception (n = 2), pregnancy (n = 8), postpartum (n = 2), or a combination (n = 10). Overall, 45% of CPGs were appraised as poor quality, 32% as moderate, and 23% as high. Evaluation of body mass index and supplementation recommendations were most common across CPGs, alongside secondary weight management recommendations for women with obesity in fewer CPGs. Accompanying recommendations for diet, physical activity, and behavior were highly variable between guidelines. We report significant ambiguity in existing guidance and an absence of important considerations, including targeting weight gain prevention and limiting excess gestational weight gain. Results emphasize the need for development of robust, comprehensive, and high quality guidelines on healthy lifestyle and weight management across these formative reproductive life stages.

The Canadian Women’s Heart Health Alliance Atlas on the Epidemiology, Diagnosis, and Management of Cardiovascular Disease in Women — Chapter 4: Sex- and Gender-Unique Disparities: CVD Across the Lifespan of a Woman

Women have unique sex- and gender-related risk factors for cardiovascular disease (CVD) that can present or evolve over their lifespan. Pregnancy-associated conditions, polycystic ovarian syndrome, and menopause can increase a woman’s risk of CVD. Women are at greater risk for autoimmune rheumatic disorders, which play a role in the predisposition and pathogenesis of CVD. The influence of traditional CVD risk factors (eg, smoking, hypertension, diabetes, obesity, physical inactivity, depression, anxiety, and family history) is greater in women than men. Finally, there are sex differences in the response to treatments for CVD risk and comorbid disease processes. In this Atlas chapter we review sex- and gender-unique CVD risk factors that can occur across a woman’s lifespan, with the aim to reduce knowledge gaps and guide the development of optimal strategies for awareness and treatment.

Impact of Obesity on Outcomes of Pregnancy in Women With Heart Disease

BACKGROUND

Women with heart disease are at risk for complications during pregnancy. This study sought to examine the effect of maternal obesity on pregnancy complications in women with heart disease.

OBJECTIVES

The objective was to determine the incidence of adverse cardiac events (CE) in pregnant women with heart disease and obesity.

METHODS

Adverse CE during pregnancy were examined in a prospective cohort of women with heart disease. CE were a composite of the following: cardiac death/arrest, arrhythmias, heart failure, myocardial infarction, stroke, aortic dissection, and thromboembolic events. Pre-eclampsia and post-partum hemorrhage were also studied. Outcomes were examined according to body mass index (BMI). To identify additional predictors of CE, a baseline risk score (CARPREG [Canadian Cardiac Disease in Pregnancy Study] II score) for predicting cardiac complications was calculated for all pregnancies and included in a multivariable logistic regression model.

RESULTS

Of 790 pregnancies, 19% occurred in women with BMI ≥30 kg/m² (obesity), 25% in women with BMI 25 to 29.9 kg/m² (overweight), 53% in women with BMI 18.5 to 24.9 kg/m² (normal weight), and 3% in women with BMI <18.5 kg/m² (underweight). Women with obesity were at higher risk of CE when compared with women with normal weight (23% vs. 14%; p = 0.006). In a multivariable model, obesity (odds ratio: 1.7; 95% confidence interval: 1.0 to 2.7) and higher CARPREG II risk scores (odds ratio: 1.7; 95% confidence interval: 1.5 to 1.9) predicted CE. Pre-eclampsia was more frequent in women with obesity compared with those with normal weight (8% vs. 2%; p = 0.001).

CONCLUSIONS

Obesity increases the risk of maternal cardiovascular complications in pregnant women with heart disease. This modifiable risk factor should be addressed at the time of preconception counseling.

Oxytocin at elective caesarean delivery: a dose-finding study in women with obesity

Prophylactic oxytocin administration at the third stage of labour reduces blood loss and the need for additional uterotonic drugs. Obesity is known to be associated with an increased risk of uterine atony and postpartum haemorrhage. It is unknown whether women with obesity require higher doses of oxytocin in order to achieve adequate uterine tone after delivery. The purpose of this study was to establish the bolus dose of oxytocin required to initiate effective uterine contraction in 90% of women with obesity (the ED₉₀ ) at elective caesarean delivery. We conducted a double-blind dose-finding study using the biased coin up-down design method. Term pregnant women with a BMI ≥ 40 kg.m^-2 undergoing elective caesarean delivery under regional anaesthesia were included. Those with conditions predisposing to postpartum haemorrhage were not included. Oxytocin was administered as an intravenous bolus over 1 minute upon delivery of the fetus. With the first woman receiving 0.5 IU, oxytocin doses were administered according to a sequential allocation scheme. The primary outcome measure was satisfactory uterine tone, as assessed by the operating obstetrician 2 minutes after administration of the oxytocin bolus. Secondary outcomes included the need for rescue uterotonic drugs, adverse effects and estimated blood loss. We studied 30 women with a mean (SD) BMI of 52.3 (7.6) kg.m^-2 . The ED₉₀ for oxytocin was 0.75 IU (95%CI 0.5-0.93 IU) by isotonic regression and 0.78 IU (95%CI 0.68-0.88 IU) by the Dixon and Mood method. Our results suggest that women with a BMI ≥ 40 kg.m^-2 require approximately twice as much oxytocin as those with a BMI < 40 kg.m^-2 , in whom an ED₉₀ of 0.35 IU (95%CI 0.15-0.52 IU) has previously been demonstrated.