Survey of Mode of Delivery and Maternal and Perinatal Outcomes in Canada.

OBJECTIVE: To identify determinants of cesarean delivery (CD) and examine associations between mode of delivery (MOD) and maternal and perinatal outcomes. METHODS: We conducted a retrospective analysis of a Canadian multicentre birth cohort derived from provincial data collected in 2008/2009. Maternal and perinatal characteristics and outcomes were compared between vaginal and cesarean birth and between the following MOD subgroups: spontaneous vaginal delivery (VD), assisted VD, planned cesarean delivery (CD), and intrapartum CD. Multivariate regression identified determinants of CD and the effects of MOD and previous CD on maternal and perinatal outcomes. RESULTS: The cohort included 264 755 births (72.1% VD and 27.9% CD) from 91 participating institutions. Determinants of CD included maternal age, parity, previous CD, chronic hypertension, diabetes, urinary tract infection or pyelonephritis, gestational hypertension, vaginal bleeding, labour induction, pre-term gestational age, low birth weight, large for gestational age, malpresentation, and male sex. CD was associated with greater risk of maternal and perinatal morbidity and mortality. Subgroup analysis demonstrated higher risk of adverse pregnancy outcomes with assisted VD and intrapartum CD than spontaneous VD. Planned CD reduced the risk of obstetric wound hematoma and perinatal mortality but increased maternal and neonatal morbidity. Previous CD increased the risk of maternal and neonatal morbidity among multiparous women. CONCLUSIONS: The CD rate in Canada is consistent with global trends reflecting demographic and obstetric intervention factors. The risk of adverse pregnancy outcomes with CD warrants evaluation of interventions to safely prevent nonessential cesarean birth.

Stillbirth in Canada: anachronistic definition and registration processes impede public health surveillance and clinical care.

The archaic definition and registration processes for stillbirth currently prevalent in Canada impede both clinical care and public health. The situation is fraught because of definitional problems related to the inclusion of induced abortions at ≥20 weeks' gestation as stillbirths: widespread uptake of prenatal diagnosis and induced abortion for serious congenital anomalies has resulted in an artefactual temporal increase in stillbirth rates in Canada and placed the country in an unfavourable position in international (stillbirth) rankings. Other problems with the Canadian stillbirth definition and registration processes extend to the inclusion of fetal reductions (for multi-fetal pregnancy) as stillbirths, and the use of inconsistent viability criteria for reporting stillbirth. This paper reviews the history of stillbirth registration in Canada, provides a rationale for updating the definition of fetal death and recommends a new definition and improved processes for fetal death registration. The recommendations proposed are intended to serve as a starting point for reformulating issues related to stillbirth, with the hope that building a consensus regarding a definition and registration procedures will facilitate clinical care and public health.

RéSUMé: La définition et les méthodes d'enregistrement archaïques des mortinaissances qui prévalent actuellement au Canada entravent à la fois les soins cliniques et la santé publique. La situation est délicate à cause des problèmes de définition que pose l'inclusion des avortements provoqués à ≥ 20 semaines de gestation parmi les mortinaissances : le recours généralisé au diagnostic prénatal et les avortements provoqués en cas d'anomalies congénitales graves ont entraîné une augmentation temporelle artéfactuelle des taux de mortinatalité au Canada et placé le pays dans une position défavorable dans les classements internationaux (de la mortinatalité). Les autres problèmes dans la définition et les méthodes d'enregistrement canadiennes des mortinaissances sont l'inclusion de la réduction fœtale (pour les grossesses multifœtales) parmi les mortinaissances et l'emploi de critères de viabilité inconsistants pour déclarer les mortinaissances. Nous examinons ici l'histoire de l'enregistrement des mortinaissances au Canada, nous justifions une révision possible de la définition de la mort fœtale et nous recommandons une nouvelle définition et des méthodes d'enregistrement améliorées des morts fœtales. Les recommandations proposées se veulent un point de départ à une reformulation des questions liées à la mortinatalité, dans l'espoir que l'établissement d'un consensus sur une définition et sur les méthodes d'enregistrement facilitera les soins cliniques et la santé publique.

Severe maternal morbidity surveillance: Monitoring pregnant women at high risk for prolonged hospitalisation and death.

BACKGROUND: There is no international consensus on the definition and components of severe maternal morbidity (SMM). OBJECTIVES: To propose a comprehensive definition of SMM, to create an empirically justified list of SMM types and subtypes, and to use this to examine SMM in Canada. METHODS: Severe maternal morbidity was defined as a set of heterogeneous maternal conditions known to be associated with severe illness and with prolonged hospitalisation or high case fatality. Candidate SMM types/subtypes were evaluated using information on all hospital deliveries in Canada (excluding Quebec), 2006-2015. SMM rates for 2012-2016 were quantified as a composite and as SMM types/subtypes. Rate ratios and population attributable fractions (PAF) associated with overall and specific SMM types/subtypes were estimated in relation to length of hospital stay (LOS > 7 days) and case fatality. RESULTS: There were 22 799 cases of SMM subtypes (among 1 418 545 deliveries) that were associated with a prolonged LOS or high case fatality. Between 2012 and 2016, the composite SMM rate was 16.1 (95% confidence interval [CI] 15.9, 16.3) per 1000 deliveries. Severe pre-eclampsia and HELLP syndrome (514.6 per 100 000 deliveries), and severe postpartum haemorrhage (433.2 per 100 000 deliveries) were the most common SMM types, while case fatality rates among SMM subtypes were highest among women who had cardiac arrest and resuscitation (241.1 per 1000), hepatic failure (147.1 per 1000), dialysis (67.6 per 1000), and cerebrovascular accident/stroke (51.0 per 1000). The PAF for prolonged hospital stay related to SMM was 17.8% (95% CI 17.3, 18.3), while the PAF for maternal death associated with SMM was 88.0% (95% CI 74.6, 94.4). CONCLUSIONS: The proposed definition of SMM and associated list of SMM subtypes could be used for standardised SMM surveillance, with rate ratios and PAFs associated with specific SMM types/subtypes serving to inform clinical practice and public health policy.

Severe Maternal Morbidity in Canada: Temporal Trends and Regional Variations, 2003-2016.

OBJECTIVE: This study sought to quantify temporal trends and provincial and territorial variations in severe maternal morbidity (SMM) in Canada. METHODS: The study used data on all hospital deliveries in Canada (excluding Québec) from 2003 to 2016 to examine temporal trends and from 2012 to 2016 to study regional variations. SMM was identified using diagnosis and intervention codes. Contrasts among periods and regions were quantified using rate ratios (RRs) and 95% confidence intervals (CIs). Temporal changes were also assessed using chi-square tests for trend (Canadian Task Force Classification II-1). RESULTS: The study population included 3 882 790 deliveries between 2003 and 2016 and 1 418 545 deliveries between 2012 and 2016. Severe hemorrhage rates increased from 44.8 in 2003 to 62.4 per 10 000 deliveries in 2012 (P for trend <0.0001) and then declined to 41.8 per 10 000 deliveries in 2016 (P for trend <0.0001). Maternal intensive care unit admission and sepsis rates decreased between 2003 and 2016, whereas rates of stroke, severe uterine rupture, hysterectomy, obstetric embolism, shock, and assisted ventilation increased. Rates of composite SMM in 2012-2016 were higher in Newfoundland and Labrador (RR 1.15; 95% CI 1.04-1.26), Nova Scotia (RR 1.11; 95% CI 1.03-1.19), New Brunswick (RR1.22; 95% CI 1.13-1.32), Manitoba (RR 1.09; 95% CI 1.03-1.15), Saskatchewan (RR 1.15; 95% CI 1.09-1.22), the Yukon (RR 1.74; 95% CI 1.35-2.25), and Nunavut (RR 1.76; 95% CI 1.46-2.11) compared with the rest of Canada, whereas rates were lower in Alberta and British Columbia. CONCLUSION: This surveillance report helps inform clinical practice and public health policy for improving maternal health in Canada.

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.