Maternal super-obesity and perinatal outcomes in Australia: a national population-based cohort study

Maternal super obesity is increasing and is associated with an increased risk of pregnancy complications-a call for concern

OBJECTIVE

This study aimed to assess the relationship of increased body mass index (BMI) with pregnancy complications.

STUDY DESIGN

We obtained data for a retrospective cohort of singleton live births using an electronic birth certificate database from 2010 to 2022. Institutional review board exemption was obtained. BMI was assessed as a continuous variable and a categorical variable with groups of BMI 18.5-29.9 kg/m2, 40-49.9 kg/m2, and ≥50 kg/m2 compared to patients with BMI 30-39.9 kg/m2. Primary outcomes were pregnancy and maternal outcomes. Secondary outcomes were neonatal outcomes. ANOVA and χ2 were used to compare continuous and categorical variables respectively, and logistic regression was used to obtain adjusted odds ratios for primary and secondary outcomes.

RESULTS

There were 223,837 patients with singleton live births with mean BMI 27.86 kg/m2. 54,385 (24.3%) had BMI 30-39.9 kg/m2, 13,299 (5.9%) had BMI 40-49.9 kg/m2, and 1,958 (0.87%) had BMI ≥50 kg/m2. Patients with BMI > 50 kg/m2 have a higher likelihood of APGAR scores <7 (aOR 1.38, 95% CI 1.05-1.83), and NICU admission or transfer out of facility (aOR 1.17, 95% CI 1.02-1.34). In the nulliparous subgroup analysis, For patients with BMI >50 kg/m2, there was a higher odds of preterm birth <37 weeks (aOR 1.57, 95% CI 1.23-2.00) and preterm birth <34 weeks (aOR 1.51 95% CI 1.00-2.30. There is also an increased odds of cesarean section in both of these BMI groups (aOR 1.68 95% CI 1.57-1.79 and aOR 2.30 95% CI 1.94-2.72).

CONCLUSION

BMI ≥ 50 kg/m2 was significantly associated with increased pregnancy complications.

The PPOS protocol mitigates the detrimental effects of high BMI on embryo and clinical pregnancy outcomes

BACKGROUND

The impact of high body mass index (BMI) on embryo and pregnancy outcomes in women using the PPOS (progestin-primed ovarian stimulation) protocol during their first frozen embryo transfer (FET) cycles is not clear. This study is to investigate the impact of BMI on oocyte, embryo, and pregnancy outcomes in patients who underwent the PPOS protocol.

METHODS

This retrospective study included the first FET cycle of 22,392 patients following the PPOS protocol. The impact of BMI on oocyte and pregnancy outcomes was assessed across different BMI groups, using direct acyclic graph to determine covariates, followed by the application of multiple linear and logistic regressions to further validate this influence.

RESULTS

The high BMI groups exhibited a higher number of oocytes; however, no significant differences were observed in good-quality embryos, clinical pregnancy rate, and implantation rate. Nevertheless, the high BMI groups demonstrated a significantly elevated miscarriage rate (9.9% vs. 12.2% vs. 15.7% vs. 18.3%, P < 0.001), particularly in late miscarriages, resulting in lower live birth rates (LBR, 41.1% vs. 40.2% vs. 37.3% vs. 36.2%, P = 0.001). These findings were further confirmed through multiple liner and logistic regression analyses. Additionally, several maternal factors showed significant associations with adjusted odds ratios for early miscarriage. However, women with a BMI ≥ 24 who underwent hormone replacement cycle or hMG late stimulation protocol for endometrial preparation experienced an increased risk of late miscarriage.

CONCLUSIONS

By utilizing the PPOS protocol, women with a high BMI exhibit comparable outcomes in terms of embryo and clinical pregnancies. However, an elevated BMI is associated with an increased risk of miscarriage, leading to a lower LBR. Adopting appropriate endometrial preparation protocols such as natural cycles and letrozole stimulation cycles may potentially offer benefits in reducing miscarriages.

Maternal and perinatal outcomes in nulliparous women with a booking body mass index exceeding 50 kg/m2

BACKGROUND

Women with a body mass index (BMI) >35 kg/m2 carry an increased obstetric risk; however, the experience of the Class IV and above obese nulliparous women is less understood.

AIMS

To describe maternal and perinatal outcomes in nulliparous women of booking BMI > 50 kg/m2.

MATERIALS AND METHODS

A cohort study of 48 nulliparous women who delivered between 2015 and 2019 in a tertiary hospital and had a booking BMI > 50 kg/m2. Obstetric outcome data was collated via electronic and written patient records. The relationship between mode of delivery and BMI was assessed using direct logistic regression. Multiple pregnancies and severe congenital malformations (n = 3) were excluded.

RESULTS

The mean booking BMI was 53.7 kg/m2 (SD 4.05) and mean maternal age was 30.4 years (SD = 5.7). Comorbidities included asthma (43%), essential hypertension (20%) and diabetes (61%). Antenatally, accuracy was compromised in 80% of morphology scans (n = 35). In the perinatal period, 33 women (68.8%) were induced compared to a spontaneous onset of labour in two (4.1%) women. There were nine elective caesarean sections (CS), five of which were for breech presentation. Of those who intended on vaginal delivery (n = 35), 51% (n = 18) had an emergency CS. In these women, the risk of CS increased by a factor of 1.36 for every one point increase in BMI > 50 kg/m2. The average gestational age was 37.5 weeks (SD 2.4) with 14% (n = 6) experiencing preterm deliveries. The incidence of babies born >90th percentile for gestational age was 15 (34%).

CONCLUSION

Increased BMI impairs maternal and perinatal outcomes and significantly increases the risk of emergency CS. BMI > 50 kg/m2 is associated with higher-level interventions and obstetric complications.

Comparison of perioperative outcomes and anesthetic-related complications of morbidly obese and super-obese parturients delivering by cesarean section

OBJECTIVE

To compare the perioperative outcomes and anesthetic-related complications of morbidly obese and super-obese parturients delivering by cesarean section.

METHODS

A retrospective analysis of 6 years of data was performed. Exclusions were cases with gestational ages <24 weeks, placenta accreta spectrum, polyhydramnios, or multiple gestations.

RESULTS

The study included 494 patients whose body mass index (BMI) exceeded 40 kg/m² at delivery. Of these, 469 were morbidly obese (BMI 40-49.9; mean, 42.9 ± 2.4), and 25 were super obese (BMI >50; mean, 54.5 ± 4.2). Twenty-four (5.1%) morbidly obese women received general anesthesia. The other 445 patients (94.9%) in the morbid obesity group underwent cesarean delivery under regional anesthesia; however, some (2.2%; 10/445) received general anesthesia after regional anesthesia failed. In the super-obesity group, 23 patients (92.0%) received regional anesthesia, while two patients (8.0%) received general anesthesia. There were no cases of pulmonary aspiration, maternal deaths, or difficult or failed intubation. There was one episode of cardiac arrest in a patient with a BMI of 47.9. Among the morbidly obese and super-obese women given regional anesthesia, the super-obese patients had significantly greater volumes of ephedrine and norepinephrine consumption (p = 0.027 and 0.030), intravenous fluids (p = 0.006), and bleeding during surgery (p = 0.017). They also had more hypotensive episodes (p = 0.038). The two groups' incidences of neonatal birth asphyxia, postpartum hemorrhage, blood transfusion, and uterine atony did not differ significantly. The lengths of stay in the hospital were also comparable.

CONCLUSIONS

Among the women receiving regional anesthesia, the super-obese parturients had greater intraoperative bleeding, a higher proportion of hypotensive episodes, and a greater vasopressor requirement than the morbidly obese parturients. Anesthesiologists must prepare for the adverse perioperative events that such women risk experiencing during a delivery by cesarean section.

www.clinicaltrials.gov ID: NCT04657692.

Overweight, obesity and excessive weight gain in pregnancy as risk factors for adverse pregnancy outcomes: a narrative review

The global prevalence of overweight and obesity in pregnancy is rising and this represents a significant challenge for the management of pregnancy and delivery. Women who have a pre‐pregnancy body mass index greater than 25 kg m^–2 are more likely than those with a body mass index in the ideal range (20–24.99 kg m^–2) to have problems conceiving a child and are at greater risk of miscarriage and stillbirth. All pregnancy complications are more likely with overweight, obesity and excessive gestational weight gain, including those that pose a significant threat to the lives of mothers and babies. Labour complications arise more often when pregnancies are complicated by overweight and obesity. Pregnancy is a stage of life when women have greater openness to messages about their lifestyle and health. It is also a time when they come into greater contact with health professionals. Currently management of pregnancy weight gain and the impact of overweight tends to be poor, although a number of research studies have demonstrated that appropriate interventions based around dietary change can be effective in controlling weight gain and reducing the risk of pregnancy complications. The development of individualised and flexible plans for avoiding adverse outcomes of obesity in pregnancy will require investment in training of health professionals and better integration into normal antenatal care.

Overweight and obesity before pregnancy and excessive gestational weight gain are major determinants of risk for pregnancy loss, gestational diabetes, hypertensive conditions, labour complications and maternal death.

Pregnancy is regarded as a teachable moment when women are at their most receptive to messages about their health. However, unclear guidance on diet and physical activity, weight stigma from health professionals, inexperience and reluctance among professionals about raising issues about weight, and stretched resources put the health of women and babies at risk.

Excessive weight gain in pregnancy and post‐partum weight retention compromise future fertility and increase risk for future pregnancies.

Large randomised controlled trials have had little success in addressing excessive gestational weight gain or antenatal complications. Individualised, culturally sensitive and responsive interventions appear to have greater success.

Socioeconomic Inequalities and Obesity in South Africa-A Decomposition Analysis

Background: Prior evidence shows that inequalities are related to overweight and obesity in South Africa. Using data from a recent national study, we examine the socioeconomic inequalities associated with obesity in South Africa and the factors associated with it. Methods: We use quantitative data from the South African National Health and Nutrition Examination Survey (SANHANES-1) carried out in 2012. We estimate the concentration index (CI) to identify inequalities and decompose the CI to explore the determinants of these inequalities. Results: We confirm the existence of pro-rich inequalities associated with obesity in South Africa. The inequalities among males are larger (CI of 0.16) than among women (CI of 0.09), though more women are obese than men. Marriage increases the risk of obesity for women and men, while smoking decreases the risk of obesity among men significantly. Higher education is associated with lower inequalities among females. Conclusions: We recommend policies to focus on promoting a healthy lifestyle, including the individual’s perception of a healthy body size and image, especially among women.

A better start to life: Risk factors for, and prevention of, preterm birth in Australian First Nations women - A narrative review

The unacceptable discrepancies in health outcomes between First Nations and non-Indigenous Australians begin at birth. Preterm birth (birth before 37 completed weeks of gestation) is a major contributor to adverse short- and long-term health outcomes and mortality. Australian First Nations infants are more commonly born too early. No tangible reductions in preterm births have been made in First Nations communities. Factors contributing to high preterm birth rates in Australian First Nations infants are reviewed and interventions to reduce preterm birth in Australian First Nations women are discussed. More must be done to ensure Australian First Nations infants get a better start to life. This can only be achieved with ongoing and improved research in partnership with Australian First Nations peoples.

Epidural analgesia in the obese obstetric patient: a retrospective and comparative study with non-obese patients at a tertiary hospital

BACKGROUND AND OBJECTIVES

Obesity is becoming a frequent condition among obstetric patients. A high body mass index (BMI) has been closely related to a higher difficulty to perform the neuraxial technique and to the failure of epidural analgesia. Our study is aimed at analyzing obese obstetric patients who received neuraxial analgesia for labor at a tertiary hospital and assessing aspects related to the technique and its success.

METHODS

Retrospective observational descriptive study during one year. Women with a BMI higher than 30 were identified, and variables related to the difficulty and complications of performing the technique, and to analgesia failure rate were assessed.

RESULTS AND CONCLUSIONS

Out of 3653 patients, 27.4% had their BMI ≥ 30 kg.m-². Neuraxial techniques are difficult to be performed in obese obstetric patients, as showed by the number of puncture attempts (≥ 3 in 9.1% obese versus 5.3% in non-obese being p < 0.001), but the incidence of complications, as hematic puncture (6.6%) and accidental dural puncture (0.7%) seems to be similar in both obese and non-obese patients. The incidence of cesarean section in obese patients was 23.4% (p <  0.001). Thus, an early performance of epidural analgesia turns out to be essential to control labor pain and to avoid a general anesthesia in such high-risk patients.

Increased maternal body mass index is associated with prolonged anaesthetic and surgical times for caesarean delivery but is partially offset by clinician seniority and established epidural analgesia

BACKGROUND

Obesity is associated with higher surgical and anaesthetic morbidity and difficulties.

AIMS

We aimed to investigate associations between maternal body mass index (BMI) and the in-theatre time taken to produce an anaesthetised state or to perform surgery for caesarean delivery.

MATERIALS AND METHODS

Using the Strengthening the Reporting of Observational Studies in Epidemiology guidelines, we identified all women who underwent caesarean section at a single institution (2009-2015). The prospectively collected data arising from antenatal and peripartum care were analysed. Generalised linear regression was used to examine associations between maternal BMI and the time taken to anaesthetise the mother and the duration of surgery.

RESULTS

Of a total of 24 761 caesarean deliveries, 5607 (22.7%) women were obese at antenatal registration. In-theatre anaesthetic preparation (18 vs 32 min, P < 0.001) and surgical duration (38 vs 52 min, P < 0.001) were longer in women with BMI ≥50 kg/m² (BMI-50) than those with normal BMI (BMI-N). This difference remained significant after controlling for antenatal, intra-operative and immediate postoperative variables. Modifiable variables were identified that may mitigate the effects of severe obesity. Senior obstetric and anaesthetic care were both independently associated with a significant reduction in mean in-theatre anaesthetic preparation time and surgical duration, by 11 and three minutes respectively (P < 0.001), while epidural top-up significantly lessened mean anaesthetic in-theatre preparation duration by seven minutes (P < 0.001).

CONCLUSIONS

Obese women had greater anaesthesia and surgery time, but the effect may potentially be mitigated by provision of care by experienced staff and prior establishment of epidural analgesia.

Interaction of chorioamnionitis at term with maternal, fetal and obstetrical factors as predictors of neonatal mortality: a population-based cohort study

Background

Chorioamnionitis is a frequent complication of pregnancy and is known to be associated with serious adverse post-natal outcomes including death. However, the assessment of fetal well-being in labor in the context of chorioamnionitis is often challenging because of fetal tachycardia. Identifying specific risk factors for adverse neonatal outcomes in the context of chorioamnionitis could therefore be of paramount importance. This study aimed to determine if maternal and fetal risk factors for increased neonatal mortality and early neonatal mortality are modified in the context of chorioamnionitis in term pregnancies.

Methods

A retrospective population-based cohort study using the United States birth/infant death public file from 2011 to 2013 was performed, including all live births at 37 weeks gestation and beyond. Interaction between chorioamnionitis and maternal demographic variables as well as labor and delivery potential risk factors were analyzed for association with neonatal death (< 28 days) and early neonatal death (< 7 days) using multivariate logistic regressions.

Results

Among 9,034,428 live births, the prevalence of chorioamionitis was 1.29% (95% CI 1.28–1.30%). The incidence of neonatal death and early neonatal death were 0.09 and 0.06% in the chorioamnionitis group versus 0.06 and 0.04% in the no chorioamnionitis group (p = 0.0003 and < 0.0001), respectively. Smoking was significantly associated with neonatal death and early neonatal death in the context of chorioamnionitis (OR 2.44, CI:1.34–4.43/ 2.36 CI:1.11–5.01) but was either less strongly or not associated in the absence of chorioamnionitis (OR 1.24, CI:1.14–1.35/0.93, CI:0.82–1.05). The association between gestational age (37 weeks compared to 39 weeks) and neonatal death was more important in the context of chorioamnionitis (OR = 3.19, CI: 1.75–5.82 versus 1.63, CI: 1.49–1.79). Multivariate analysis identified the following risk factors for neonatal death and/or early neonatal death: low maternal education, extreme maternal age, obesity (BMI > 35 kg/m²), late or no prenatal care, diabetes, meconium-stained amniotic fluid, gestational ages other than 39 weeks, neonatal weight < 2500 g and delivery by vacuum or caesarian.

Conclusions

Smoking as well as early term have a positive interaction with chorioamnionitis for the risk of neonatal mortality. This should be taken into account when counseling pregnant women and managing laboring pregnant women with suspected chorioamnionitis.

Pre-Pregnancy Obesity, Excessive Gestational Weight Gain, and the Risk of Pregnancy-Induced Hypertension and Gestational Diabetes Mellitus

Excessive pre-pregnancy weight is a known risk factor of pregnancy complications. The purpose of this analysis was to assess the relationship between several categories of maternal weight and the risk of developing hypertension and diabetes in pregnancy, and the relationship of these complications with the results of the newborn. It was carried out in a common cohort of pregnant women and taking into account the influence of disturbing factors. Our analysis was conducted in a prospective cohort of 912 Polish pregnant women, recruited during 2015-2016. We evaluated the women who subsequently developed diabetes with dietary modification (GDM-1) (n = 125) and with insulin therapy (GDM-2) (n = 21), as well as the women who developed gestational hypertension (GH) (n = 113) and preeclampsia (PE) (n = 24), compared to the healthy controls. Odds ratios of the complications (and confidence intervals (95%)) were calculated in the multivariate logistic regression. In the cohort, 10.8% of the women had pre-pregnancy obesity (body mass index (BMI) ≥ 30 kg/m²), and 36.8% had gestational weight gain (GWG) above the range of the Institute of Medicine recommendation. After correction for excessive GWG and other confounders, pre-pregnancy obesity (vs. normal BMI) was associated with a higher odds ratio of GH (AOR = 4.94; p < 0.001), PE (AOR = 8.61; p < 0.001), GDM-1 (AOR = 2.99; p < 0.001), and GDM-2 (AOR = 11.88; p <0.001). The threshold risk of development of GDM-2 occurred at lower BMI values (26.9 kg/m²), compared to GDM-1 (29.1 kg/m²). The threshold point for GH was 24.3 kg/m², and for PE 23.1 kg/m². For GWG above the range (vs. GWG in the range), the adjusted odds ratios of GH, PE, GDM-1, and GDM-2 were AOR = 1.71 (p = 0.045), AOR = 1.14 (p = 0.803), AOR = 0.74 (p = 0.245), and AOR = 0.76 (p = 0.672), respectively. The effect of maternal edema on all the results was negligible. In our cohort, hypertension and diabetes were associated with incorrect birth weight and gestational age at delivery. Conclusions: This study highlights the importance and influence of excessive pre-pregnancy maternal weight on the risk of pregnancy complications such as diabetes and hypertension which can impact fetal outcomes.

Impacts of obesity, maternal obesity and nicotinamide mononucleotide supplementation on sperm quality in mice

Male fertility and sperm quality are negatively impacted by obesity. Furthermore, recent evidence has shown that male offspring from obese rat mothers also have reduced sperm quality and fertility. Here, we extend work in this area by comparing the effects of both maternal obesity and offspring post-weaning diet-induced obesity, as well as their combination, on sperm quality in mice. We additionally tested whether administration of the NAD⁺-booster nicotinamide mononucleotide (NMN) can ameliorate the negative effects of obesity and maternal obesity on sperm quality. We previously showed that intraperitoneal (i.p.) injection of NMN can reduce the metabolic deficits induced by maternal obesity or post-weaning dietary obesity in mice. In this study, female mice were fed a high-fat diet (HFD) for 6 weeks until they were 18% heavier than a control diet group. Thereafter, HFD and control female mice were mated with control diet males, and male offspring were weaned into groups receiving control or HFD. At 30 weeks of age, mice received 500 mg/kg body weight NMN or vehicle PBS i.p. for 21 days. As expected, adiposity was increased by both maternal and post-weaning HFD but reduced by NMN supplementation. Post-weaning HFD reduced sperm count and motility, while maternal HFD increased offspring sperm DNA fragmentation and levels of aberrant sperm chromatin. There was no evidence that the combination of post-weaning and maternal HFD exacerbated the impacts in sperm quality suggesting that they impact spermatogenesis through different mechanisms. Surprisingly NMN reduced sperm count, vitality and increased sperm oxidative DNA damage, which was associated with increased NAD⁺ in testes. A subsequent experiment using oral NMN at 400 mg/kg body weight was not associated with reduced sperm viability, oxidative stress, mitochondrial dysfunction or increased NAD⁺ in testes, suggesting that the negative impacts on sperm could be dependent on dose or mode of administration.

Eclampsia in Australia and New Zealand: A prospective population-based study

BACKGROUND

Eclampsia is a serious consequence of pre-eclampsia. There are limited data from Australia and New Zealand (ANZ) on eclampsia.

AIM

To determine the incidence, management and perinatal outcomes of women with eclampsia in ANZ.

MATERIALS AND METHODS

A two-year population-based descriptive study, using the Australasian Maternity Outcomes Surveillance System (AMOSS), carried out in 263 sites in Australia, and all 24 New Zealand maternity units, during a staggered implementation over 2010-2011. Eclampsia was defined as one or more seizures during pregnancy or postpartum (up to 14 days) in any woman with clinical evidence of pre-eclampsia.

RESULTS

Of 136 women with eclampsia, 111 (83%) were in Australia and 25 (17%) in New Zealand. The estimated incidence of eclampsia was 2.2 (95% confidence interval (CI) 1.9-2.7) per 10 000 women giving birth. Aboriginal and Torres Strait Islander women were over-represented in Australia (n = 9; 8.1%). Women with antepartum eclampsia (n = 58, 42.6%) were more likely to have a preterm birth (P = 0.04). Sixty-three (47.4%) women had pre-eclampsia diagnosed prior to their first eclamptic seizure of whom 19 (30.2%) received magnesium sulphate prior to the first seizure. Nearly all women (n = 128; 95.5%) received magnesium sulphate post-seizure. No woman received prophylactic aspirin during pregnancy. Five women had a cerebrovascular haemorrhage, and there were five known perinatal deaths.

CONCLUSIONS

Eclampsia is an uncommon consequence of pre-eclampsia in ANZ. There is scope to reduce the incidence of this condition, associated with often catastrophic morbidity, through the use of low-dose aspirin and magnesium sulphate in women at higher risk.

Maternal obesity classes, preterm and post-term birth: a retrospective analysis of 479,864 births in England

BACKGROUND

Preterm (< 37 weeks gestation) and post-term birth (≥42 weeks gestation) are associated with increased morbidity and mortality for mother and infant. Obesity (body mass index (BMI) ≥30 kg/m²) is increasing in women of reproductive age. Maternal obesity has been associated with adverse pregnancy outcomes including preterm and post-term birth. However, the effect sizes vary according to the subgroups of both maternal BMI and gestational age considered. The aim of this retrospective analysis was to determine the association between maternal obesity classes and gestational age at delivery.

METHODS

A secondary data analysis of 13 maternity units in England with information on 479,864 singleton live births between 1990 and 2007. BMI categories were: underweight (< 18.5 kg/m²), recommended weight (18.5-24.9 kg/m²), overweight (25.0-29.9 kg/m²) and obesity classes I (30.0-34.9 kg/m²), II (35.0-39.9 kg/m²), IIIa (40-49.9 kg/m²) and IIIb (≥50 kg/m²). Gestational age at delivery categories were: Gestational age at delivery (weeks): extreme preterm (20-27), very preterm (28-31), moderately preterm (32-36), early term (37, 38), full term (39-40), late term (41) and post-term (≥42). The adjusted odds of births in each gestational age category (compared to full-term birth), according to maternal BMI categories were estimated using multinomial logistic regression. Missing data were estimated using multiple imputation with chained equations.

RESULTS

There was a J-shaped association between the absolute risk of extreme, very and moderate preterm birth and BMI category, with the greatest effect size for extreme preterm. The absolute risk of post-term birth increased monotonically as BMI category increased. The largest effect sizes were observed for class IIIb obesity and extreme preterm birth (adjusted OR 2.80, 95% CI 1.31-5.98).

CONCLUSION

Women with class IIIb obesity have the greatest risks for inadequate gestational age. Combining obesity classes does not accurately represent risks for many women as it overestimates the risk of all preterm and post-term categories for women with class I obesity, and underestimates the risk for women in all other obesity classes.

Venous thromboembolism prophylaxis of the obese postpartum patient: A cross-sectional study

BACKGROUND

Obesity increases risk of venous thromboembolism (VTE) in obstetric patients regardless of delivery mode and for up to six weeks postpartum.

AIM

This study aimed to examine postpartum pharmacological VTE prophylaxis practices for obese women at an Australian tertiary referral hospital.

MATERIALS AND METHODS

Medical records were retrieved for obese obstetric patients who delivered during May 2016-May 2017. Records were examined for demographic data, VTE risk factors, and LMWH (low-molecular-weight heparin) use. Due to lack of specific Australian or local guidelines, practice was evaluated using recommendations from the Royal College of Obstetricians and Gynaecologists (RCOG-UK). Patients with BMI (body mass index) <30, incomplete/unavailable medical records, and those discharged from other health services were excluded.

RESULTS

One hundred and eight postpartum patients (70 caesareans, 38 vaginal deliveries) with a BMI ≥ 30 kg/m² were reviewed. Of these patients, 53 (49.1%) had a BMI ≥ 40 kg/m² . Ninety-eight of 108 (90.7%) patients had ≥2 VTE risk factors including a BMI ≥ 30 kg/m² . One hundred and three of 108 (95.4%) patients were indicated for postpartum VTE prophylaxis with LMWH, and 77 of 103 (74.8%) patients received it. Three of five patients meeting criteria for ≥6 weeks of LMWH thromboprophylaxis had it prescribed. Of the 72 patients whose weight exceeded 90 kg and who also received LMWH, 32 (44.4%) were prescribed a weight-adjusted dose.

CONCLUSION

VTE prophylaxis practices using LMWH in obese postpartum patients, including weight-adjusting doses and extended-course prescribing, appear variable. Limited literature, recommendation discrepancies, and varied awareness of recommendations may be contributing factors. Further education and research regarding this high-risk cohort are warranted.

What Is Known About the Nutritional Intake of Women during Pregnancy Following Bariatric Surgery? A Scoping Review

Optimising the diet and weight of women prior to and during pregnancy is of paramount importance to both maternal and offspring health. In women who become pregnant after bariatric surgery, evidence suggests a better overall obstetric outcome in comparison to women with severe obesity managed conservatively. Historically, most studies in this population group have monitored supplement adherence or serum concentrations of micronutrients, rather than dietary intake. The aim of this study was to synthesise current knowledge of the dietary intake of women during pregnancy following bariatric surgery. A systematic search of search engines was conducted using the following databases: MEDLINE, Embase, CINAHL, Cochrane database, Scopus, Trip, NHS Evidence, UK Clinical Trials, ClinicalTrials.gov, Prospero, Epistemonikos and Open Grey. Titles and abstracts were screened independently by two reviewers against predefined inclusion and exclusion criteria. After removal of duplicates, 1594 titles were identified, of which 1586 were initially excluded. Following full-text review, four articles were included. In total, across all four studies, data from only 202 bariatric surgery participants were included, the majority of whom had had one type of surgery. Just one study included a control group. Reporting of nutritional outcomes was heterogenous, with none of the studies including complete macro and micronutrient intake results in their articles. An insufficient intake of protein was noted as a concern in two studies and associated with poor fetal growth in one study. Overall, this review has identified a paucity of data about the dietary intake of women during pregnancy after bariatric surgery.

Assessing Support for Advantaged and Disadvantaged Groups: A Comparison of Urban Food Environments

Individuals from lower-socio-economic status (SES) communities have increased risk of developing obesity in developed countries such as Australia. Given the influence of the environment on dietary behaviour, this paper seeks to examine food environments in areas of differing social advantage. An established measurement tool (the NEMS-Nutrition Environment Measurement Survey), that captures aspects of support for healthy eating within restaurants (NEMS-R) and grocery/convenience stores (NEMS-S), was applied to both a high-SES and a low-SES suburb within Brisbane, Australia. The study found a significantly more supportive restaurant food environment in the high-SES suburb, with greater access to and availability of healthful foods, as well as facilitators for, reduced barriers to, and substantially more nutrition information for healthful eating. A higher number of outlets were found in the high-SES suburb, and later opening times were also observed. Overall, the results from stores (NEMS-S) suggest poor support for healthful eating across both suburbs. This study highlights how food environments in low-SES regions continue to be less supportive of healthful eating. Public health strategies must move beyond individual-focused strategies to ensure that our most disadvantaged, low-SES communities have an equal opportunity to access healthful foods.

Maternal and perinatal outcomes in pregnant women with BMI >50: An international collaborative study

OBJECTIVE

To examine the association between maternal BMI>50kg/m2 during pregnancy and maternal and perinatal outcomes.

MATERIALS AND METHODS

An international cohort study was conducted using data from separate national studies in the UK and Australia. Outcomes of pregnant women with BMI>50 were compared to those of pregnant women with BMI<50. Multivariable logistic regression estimated the association between BMI>50 and perinatal and maternal outcomes.

RESULTS

932 pregnant women with BMI>50 were compared with 1232 pregnant women with BMI<50. Pregnant women with BMI>50 were slightly older, more likely to be multiparous, and have pre-existing comorbidities. There were no maternal deaths, however, extremely obese women had a nine-fold increase in the odds of thrombotic events compared to those with a BMI<50 (uOR: 9.39 (95%CI:1.15-76.43)). After adjustment, a BMI>50 during pregnancy had significantly raised odds of preeclampsia/eclampsia (aOR:4.88(95%CI: 3.11-7.65)), caesarean delivery (aOR: 2.77 (95%CI: 2.31-3.32)), induction of labour (aOR: 2.45(95% CI:2.00-2.99)) post caesarean wound infection (aOR:7.25(95%CI: 3.28-16.07)), macrosomia (aOR: 8.05(95%CI: 4.70-13.78)) compared a BMI<50. Twelve of the infants born to women in the extremely obese cohort died in the early neonatal period or were stillborn.

CONCLUSIONS

Pregnant women with BMI>50 have a high risk of inferior maternal and perinatal outcomes.

Recent Lifestyle Parameters Are Associated with Increasing Caesarean Section Rates among Singleton Term Births in Austria

Caesarean section (CS) rates are increasing in many parts of the world, recently reaching about 20% worldwide. The postmodern lifestyle characteristics, obesity and delayed childbirth, have been put forward as the main reasons for high CS rates. The present study tests the association patterns between lifestyle parameters and delivery mode on a data set of 3786 births in Vienna between 2005 and 2013. The focus is exclusively on singleton term births. As well as maternal age, prepregnancy weight status, maternal body height and gestational weight gain, newborn size (birth weight, birth length, and head circumference), Apgar scores and child presentation were recorded. Planned as well as emergency CS rates increased significantly (p < 0.0001) with increasing maternal age and decreasing maternal body height. Emergency CS rates, however, increased significantly with increasing maternal prepregnancy weight status and gestational weight gain. An especially high risk of emergency CS occurred among four groups of mothers: those older than 40 years (OR = 2.68; 95% CI 1.87⁻3.86), those who were obese (OR = 1.44; 95% 1.15⁻1.81), those experiencing a gestational weight gain above 15 kg (OR = 1.32; 95% CI 1.13⁻1.54), and those shorter than 160 cm (OR = 1.216; 95% CI 1.02⁻1.45). Emergency CS rates were significantly higher among low-weight newborns (<2500 g) and macrosome newborns (>4000 g) than among normal-weight newborns. Furthermore, breech presentation was associated with an increased risk of caesarean delivery (OR 6.97; 95% CI 6.09⁻7.96). Logistic regression analyses reveal that maternal age, maternal body height, prepregnancy weight status, gestational weight gain, birth weight, newborn head circumference and child presentation show an independent, highly significant association with caesarean delivery. We conclude that maternal and newborn characteristics typical of recent lifestyle patterns, such as advanced maternal age, obesity, increased gestational weight gain and increased newborn size, are highly significantly associated with increased emergency CS rates. Moreover, maternal shortness and breech presentation are risk factors for emergency CS.

Binational cohort study comparing the management and outcomes of pregnant women with a BMI >50-59.9 kg/m2 and those with a BMI ≥60 kg/m2

OBJECTIVES

To compare the management, maternal and perinatal outcomes of women with a body mass index (BMI) ≥60 kg/m² with women with a BMI >50-59.9 kg/m².

DESIGN

International collaborative cohort study.

SETTING

Binational study in the UK and Australia.

PARTICIPANTS

UK: all pregnant women, and Australia: women who gave birth (birth weight ≥400 g or gestation ≥20 weeks) METHODS: Data from the Australasian Maternity Outcomes Surveillance System and UK Obstetric Surveillance System. Management, maternal and infant outcomes were compared between women with a BMI ≥60 kg/m² and women with a BMI >50-59.9 kg/m², using unconditional logistic regression.

RESULTS

The sociodemographic characteristics and previous medical histories were similar between the 111 women with a BMI ≥60 kg/m² and the 821 women with a BMI >50-59.9 kg/m². Women with a BMI ≥60 kg/m² had higher odds of thromboprophylaxis usage in both the antenatal (24% vs. 12%; OR 2.25, 95% CI 1.39 to 3.64) and postpartum periods (78% vs. 66%; OR 1.68, 95% CI 1.04 to 2.70). Women with BMI ≥60 kg/m² had nearly double the odds of pre-eclampsia/eclampsia (adjusted OR 1.83 (95% CI 1.01 to 3.30)). No other maternal or perinatal outcomes were statistically significantly different. Severe adverse outcomes such as perinatal death were uncommon in both groups thus limiting the power of these comparisons. The rate of perinatal deaths was 18 per 1000 births for those with BMI ≥60 kg/m²; 12 per 1000 births for those with BMI >50-59.9 kg/m²; those with BMI ≥60 kg/m² had a non-significant increased odds of perinatal death (unadjusted OR 1.46, 95% CI 0.31 to 6.74).

CONCLUSIONS

Women are managed differently on the basis of BMI even at this extreme as shown by thromboprophylaxis. The pre-eclampsia result suggests that future research should examine whether weight reduction of any amount prior to pregnancy could reduce poor outcomes even if women remain extremely obese.

Epidural extension failure in obese women is comparable to that of non-obese women

BACKGROUND

Management of labor epidurals in obese women is difficult and extension to surgical anesthesia is not always successful. Our previous retrospective pilot study found epidural extension was more likely to fail in obese women. This study used a prospective cohort to compare the failure rate of epidural extension in obese and non-obese women and to identify risk factors for extension failure.

METHODS

One hundred obese participants (Group O, body mass index ≥ 40 kg/m² ) were prospectively identified and allocated two sequential controls (Group C, body mass index ≤ 30 kg/m² ). All subjects utilized epidural labor analgesia and subsequently required anesthesia for cesarean section. The primary outcome measure was failure of the labor epidural to be used as the primary anesthetic technique. Risk factors for extension failure were identified using Chi-squared and logistic regression.

RESULTS

The odds ratio (OR) of extension failure was 1.69 in Group O (20% vs. 13%; 95% CI: 0.88-3.21, P = 0.11). Risk factors for failure in obese women included ineffective labor analgesia requiring anesthesiologist intervention, (OR 3.94, 95% CI: 1.16-13.45, P = 0.028) and BMI > 50 kg/m² (OR 3.42, 95% CI: 1.07-10.96, P = 0.038).

CONCLUSION

The failure rate of epidural extension did not differ significantly between the groups. Further research is needed to determine the influence of body mass index > 50 kg/m² on epidural extension for cesarean section.

Incidence, risk factors and perinatal outcomes for placenta accreta in Australia and New Zealand: a case-control study

OBJECTIVE

Estimate the incidence of placenta accreta and describe risk factors, clinical practice and perinatal outcomes.

DESIGN

Case-control study.

SETTING

Sites in Australia and New Zealand with at least 50 births per year.

PARTICIPANTS

Cases were women giving birth (≥20 weeks or fetus ≥400 g) who were diagnosed with placenta accreta by antenatal imaging, at operation or by pathology specimens between 2010 and 2012. Controls were two births immediately prior to a case. A total of 295 cases were included and 570 controls.

METHODS

Data were collected using the Australasian Maternity Outcomes Surveillance System.

PRIMARY AND SECONDARY OUTCOME MEASURES

Incidence, risk factors (eg, prior caesarean section (CS), maternal age) and clinical outcomes of placenta accreta (eg CS, hysterectomy and death).

RESULTS

The incidence of placenta accreta was 44.2/100 000 women giving birth (95% CI 39.4 to 49.5); however, this may overestimated due to the case definition used. In primiparous women, an increased odds of placenta accreta was observed in older women (adjusted OR (AOR) women≥40 vs <30: 19.1, 95% CI 4.6 to 80.3) and current multiple birth (AOR: 6.1, 95% CI 1.1 to 34.1). In multiparous women, independent risk factors were prior CS (AOR ≥2 prior sections vs 0: 13.8, 95% CI 7.4 to 26.1) and current placenta praevia (AOR: 36.3, 95% CI 14.0 to 93.7). There were two maternal deaths (case fatality rate 0.7%).Women with placenta accreta were more likely to have a caesarean section (AOR: 4.6, 95% CI 2.7 to 7.6) to be admitted to the intensive care unit (ICU)/high dependency unit (AOR: 46.1, 95% CI 22.3 to 95.4) and to have a hysterectomy (AOR: 209.0, 95% CI 19.9 to 875.0). Babies born to women with placenta accreta were more likely to be preterm, be admitted to neonatal ICU and require resuscitation.

Maternal super obesity and risk for intensive care unit admission in the MFMU Cesarean Registry

INTRODUCTION

Obesity is a risk factor for intensive care unit (ICU) admission in nonpregnant populations. Less is known about maternal obesity and ICU admission risk. The objective of this study was to estimate the association between maternal obesity and ICU admission among women who delivered via cesarean section or vaginal birth after cesarean section (VBAC).

MATERIAL AND METHODS

This is a retrospective cohort analysis of women who delivered via VBAC or cesarean section in the Maternal-Fetal Medicine Unit (MFMU) Cesarean Registry. We defined exposure as body mass index (BMI) at delivery stratified as non-obese (BMI 18.5-29.9 kg/m² ), class I or II obese (BMI 30-39.9 kg/m² ), morbidly obese (BMI 40-49.9 kg/m² ), and super obese (BMI ≥ 50 kg/m² ). The primary outcome was ICU admission. Modified Poisson regression models estimated relative risk (RR) of ICU admission by obesity strata, after adjusting for confounders. Mediation analysis was used to estimate the proportion of ICU admission risk attributable specifically to obesity.

RESULTS

We included 68 455 women; 40% non-obese, 46% class I or II obese, 12% morbidly obese, and 2% super obese. Super obese women were at higher risk for ICU admission compared with non-obese women (0.7 vs. 1.3%, adjusted RR 1.61; 95% CI 1.01-2.65), after adjusting for confounders. Among super obese women, medical comorbidities mediated 58% of ICU admission risk, suggesting that a significant proportion of ICU admission is driven by maternal obesity.

CONCLUSIONS

Super obese women who deliver by cesarean section or VBAC are at increased risk of peripartum ICU admission. Obstetricians and critical care specialists should consider possible ICU admission during delivery planning.

Associations of maternal pre-pregnancy body mass index and gestational weight gain with birth outcomes in Shanghai, China

Recent data suggests that abnormal maternal pre-pregnancy body mass index (BMI) or gestational weight gain (GWG) is associated with unfavorable delivery outcomes. However, limited clinical evidence is available to support this correlation in China. Participating 510 mother-infant pairs were recruited from the Shanghai First Maternity and Infant Hospital, China, between January 1^st and 30^th 2016. Maternal pre-pregnancy BMI was categorized according to the China’s classification and GWG according to the 2009 Institute of Medicine recommendations (IOM). Linear regression tested the associations between pre-pregnancy BMI or GWG and length of gestation, birthweight, length, and head circumference. Logistic regression assessed the associations between pre-pregnancy BMI or GWG and macrosomic, small- (SGA) and large- (LGA) for-gestational-age infants. Overweight/obese women showed increased length of gestation and birthweight, but did not have a higher risk of macrosomic and LGA infants compared with normal weight women. Women with excessive GWG showed increased length of gestation, birthweight, length, and head circumference, and were more likely to deliver macrosomic and LGA infants compared with women with adequate GWG. Although a relatively low proportion of women from Shanghai area are overweight/obese or exhibit excessive GWG, both high pre-pregnancy BMI and excessive GWG influence perinatal outcomes.

Anaesthetic Management of Obese Parturients: What is the Evidence Supporting Practice Guidelines?

Increasing rates of obesity in western populations present management difficulties for clinicians caring for obese pregnant women. Various governing bodies have published clinical guidelines for the care of obese parturients. These guidelines refer to two components of anaesthetic care: anaesthetic consultation in the antenatal period for women with a body mass index (BMI) > 40 kg/m2 and the provision of early epidural analgesia in labour. These recommendations are based on the increased incidence of obstetric complications and the predicted risks and difficulties in providing anaesthetic care. The concept behind early epidural analgesia is logical—site the epidural early, use it for surgical anaesthesia and avoid general anaesthesia if surgery is required. Experts support this recommendation, but there is weak supporting evidence. It is known that the management of labour epidurals in obese women is complicated and that women with extreme obesity require higher rates of general anaesthesia. Anecdotally, anaesthetists view and apply the early epidural recommendation inconsistently and the acceptability of early epidural analgesia to pregnant women is variable. In this topic review, we critically appraise these two practice recommendations. The elements required for effective implementation in multidisciplinary maternity care are considered. We identify gaps in the current literature and suggest areas for future research. While prospective cohort studies addressing epidural extension (‘top-up’) in obese parturients would help inform practice, audit of local practice may better answer the question “is early epidural analgesia beneficial to obese women in my practice?”.