The impact of isolated obesity compared with obesity and other risk factors on risk of stillbirth: a retrospective cohort study.

BACKGROUND: Maternal obesity is associated with stillbirth, but uncertainty persists around the effects of higher obesity classes. We sought to compare the risk of stillbirth associated with maternal obesity alone versus maternal obesity and additional or undiagnosed factors contributing to high-risk pregnancy. METHODS: We conducted a retrospective cohort study using the Better Outcomes Registry and Network (BORN) for singleton hospital births in Ontario between 2012 and 2018. We used multivariable Cox proportional hazard regression and logistic regression to evaluate the relationship between prepregnancy maternal body mass index (BMI) class and stillbirth (reference was normal BMI). We treated maternal characteristics and obstetrical complications as independent covariates. We performed mediator analyses to measure the direct and indirect effects of BMI on stillbirth through major common-pathway complications. We used fully adjusted and partially adjusted models, representing the impact of maternal obesity alone and maternal obesity with other risk factors on stillbirth, respectively. RESULTS: We analyzed data on 681 178 births between 2012 and 2018, of which 1956 were stillbirths. Class I obesity was associated with an increased incidence of stillbirth (adjusted hazard ratio [HR] 1.55, 95% confidence interval [CI] 1.35-1.78). This association was stronger for class III obesity (adjusted HR 1.80, 95% CI 1.44-2.24), and strongest for class II obesity (adjusted HR 2.17, 95% CI 1.83-2.57). Plotting point estimates for odds ratios, stratified by gestational age, showed a marked increase in the relative odds for stillbirth beyond 37 weeks' gestation for those with obesity with and without other risk factors, compared with those with normal BMI. The impact of potential mediators was minimal. INTERPRETATION: Maternal obesity alone and obesity with other risk factors are associated with an increased risk of stillbirth. This risk increases with gestational age, especially at term.

Does late second-trimester cervical length predict unscheduled preterm birth in asymptomatic triplet pregnancies?

OBJECTIVE: Multiple gestation increases the risk of unscheduled preterm birth (PTB), both spontaneous and indicated, leading to increased neonatal morbidity and additional healthcare costs. The purpose of this study was to determine whether cervical length (CL) assessment by 28 weeks could predict unscheduled PTB <34 weeks in triplet pregnancies. Secondary outcomes included prediction of PTB <30 weeks, prediction of PTB based on degree of cervical change and effect of ART-use on PTB. METHODS: This was a retrospective cohort of women with triplet pregnancies. The exposure variable of interest was short cervix < 25 and <20 millimeters (mm) by 28 weeks. Maternal characteristics were described. The distribution of CLs was analyzed by the primary outcome of unscheduled PTB < 34 weeks, and by PTB <30 weeks (secondary outcome). Gestational age at delivery was compared between women with and without a short cervix. Changes in CL were compared between the groups with unscheduled PTB and those delivering ≥34 and ≥30 weeks. Statistical analyses were performed using appropriate tests. RESULTS: Of 92 triplet pregnancies, 51 met the criteria, with 1233 total (411 shortest) CL measurements from 16 to 34 weeks' gestation. The overall rate of PTB <34 weeks was 31.4% and <30 weeks was 9.8%. The median gestational age at delivery was 32.7 (IQR 2.3) weeks. There were no statistically significant differences in rates of unscheduled PTB in women who had a short cervix and those that did not: PTB <34 weeks with CL <25 mm (p = .53) and CL <20 mm (p = .70); PTB <30 weeks with CL <25 mm (p = .38) and CL <20 mm (p = .26). The degree of cervical change from 18 to 28 weeks was not statistically significant for predicting unscheduled PTB <34 and <30 weeks. Of 70.6% of triplet pregnancies conceived by ARTs, 13.9% had unscheduled PTB <30 weeks, whereas no spontaneously-conceived pregnancies delivered <30 weeks (p = .14). CONCLUSION: Short cervix did not predict unscheduled spontaneous PTB <34 weeks nor <30 weeks in our triplet cohort, nor did the degree of cervical change by 28 weeks predict PTB. Triplets conceived by ARTs may have an increased risk of unscheduled PTB.

Bioethics of Translating Limited Evidence into Clinical Practice: Case Study of the Cerebroplacental Ratio.

Bioethics can help address the challenges of translating research into clinical practice in the twenty-first century. The cerebroplacental ratio in obstetrical ultrasound provides a case study of how bioethical principles can help advance practical approaches when evidence is limited. This can help clinicians use cerebroplacental ratio when additional risk factors are present in critical cases that warrant increased surveillance; disclose limited information appropriately; allocate resources; and weigh benefits against risks. Balancing the key ethical principles of respect for autonomy, beneficence, non-maleficence, and justice within this context illuminates how bioethics can assist health care providers as well as help set a research agenda. Such analyses are essential to improving clinical care, given the rapid pace at which medicine is evolving.

A comparison of breastfeeding rates by obesity class.

PURPOSE: The purpose of this study is to compare breastfeeding initiation rates for women across body mass index (BMI) classes, including normal BMI (18.50-24.99 kg/m2), overweight (25.00-29.99 kg/m2), obese (30.00-39.99 kg/m2), morbidly obese (40.00-49.99 kg/m2) and extreme obesity (≥50.00 kg/m2). MATERIALS AND METHODS: Retrospective cohort of women with singleton pregnancies, delivering in St. John's, NL between 2002 and 2011. The primary outcome was any breastfeeding on hospital discharge. Breastfeeding rates across BMI categories were compared, using univariate analyses. Multivariate analysis included additional maternal and obstetric variables. RESULTS: Twelve thousand four hundred twenty-two women were included: 8430 breastfed and 3992 did not breastfeed on hospital discharge. Progressively decreasing rates of breastfeeding were noted with increasing obesity class: normal BMI (71.1%), overweight (69.1%), obese (61.6%), morbidly obese (54.2%), and extremely obese women (42.3%). Multivariate analysis confirmed that increasing obesity class resulted in lower odds of breastfeeding: overweight (adjusted odds ratios (aOR) 0.86, 95%CI 0.76-0.98), obese (aOR 0.65, 95%CI 0.57-0.74), morbidly obese (aOR 0.57, 95%CI 0.44-0.74), and extreme obesity (aOR 0.37, 95%CI 0.19-0.74). CONCLUSION: Women in higher obesity classes are progressively less likely to initiate breastfeeding. Women with the highest prepregnancy BMIs should be particularly counseled on the benefits of breastfeeding.

The Impact of Maternal Obesity on Breastfeeding.

OBJECTIVE: To compare the rate of any breastfeeding at the time of postpartum hospital discharge between obese women (BMI ≥ 30.00 kg/m(2)) and women with a normal BMI (18.50 to 24.99 kg/m(2)). METHODS: We conducted a retrospective cohort study of women with live, singleton pregnancies who delivered in St. John's, Newfoundland and Labrador between 2002 and 2011, using data from the Newfoundland and Labrador provincial perinatal registry. The primary outcome was any breastfeeding at the time of discharge from hospital. Secondary analysis included comparison of breastfeeding rates by class of obesity. We compared additional maternal and neonatal outcomes between women who were breastfeeding at discharge and those who were not. Univariate and multivariate logistic regression analyses were performed, and adjusted odds ratios (aORs) and 95% CIs were calculated. RESULTS: We included 12 831 women with BMI data available in the study: 8676 were breastfeeding and 4155 were not at the time of postpartum discharge. Obese women were less likely to breastfeed than women with normal weight (60.0% vs. 71.7%) (aOR 0.63; 95% CI 0.55 to 0.71). Multivariate analysis showed a significant effect on the primary outcome of a mother's age (aOR 1.03; 95% CI 1.02 to 1.05), nulliparity (aOR 1.73; 95% CI 1.51 to 1.98), being partnered (aOR 1.57; 95% CI 1.34 to 1.84), working (aOR 1.10; 95% CI 1.02 to 1.19), having higher education (aOR 1.48; 95% CI 1.38 to 1.60), smoking (aOR 0.35; 95% CI 0.29 to 0.43), having gestational diabetes (aOR 0.70; 95% CI 0.5 to 0.92), pre-existing hypertension (aOR 0.58; 95% CI 0.39 to 0.87), gestational hypertension (aOR 0.67; 95% CI 0.55 to 0.82), and undergoing general anaesthesia (aOR 0.41; 95% CI 0.22 to 0.77). CONCLUSION: Obesity is an independent risk factor for not breastfeeding at the time of postpartum discharge from hospital. It is important to counsel women on the benefits of breastfeeding, emphasizing these particularly in women with a high pre-pregnancy BMI.