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.

Committee Opinion No. 419: Coercion Free Contraceptive Care.

OBJECTIVE: To provide guidance on culturally competent contraception counselling that is free of coercion and promotes shared decision-making and patient autonomy. TARGET POPULATION: Individuals of reproductive age who seek contraception or counselling for family planning. OPTIONS: Contraception counselling is provided within a rights-based family planning framework, where the individual's beliefs, culture, preferences, and ability to use the chosen method are respected. OUTCOMES: To promote patient autonomy in decision-making surrounding family planning, including the right to access and use their contraceptive method of choice, to decline contraception or use less effective methods of contraception, and to freely choose to discontinue a method of contraception, as well as the right to unbiased, non-coercive contraception counselling and evidence-based information from their health care provider BENEFITS, HARMS, AND COSTS: Implementation of these recommendations would reduce real or perceived coercive contraceptive care, particularly among vulnerable populations, resulting in improved patient autonomy and a better patient experience in health care settings. EVIDENCE: Databases searched: MEDLINE, Cochrane, PubMed, and CanLII. Medical terms used: contraception, family planning services, informed consent, coercion, decision making, sterilization, permanent contraception, counselling. Legal terms searched: forced sterilization, and aboriginal. Initial search conducted in 2020 and updated in 2021. INTENDED AUDIENCE: This committee opinion is intended for health care providers (obstetricians, gynaecologists, family physicians, general surgeons, nurse practitioners, nurses, midwives, undergraduate/postgraduate medical trainees, and other health care providers) who provide sexual and reproductive health services.

Compliance with Fetal Fibronectin Testing at a Canadian Tertiary Care Perinatal Centre.

OBJECTIVE: The purpose of this study was to assess compliance with fetal fibronectin (fFN) testing recommendations at a single tertiary care perinatal centre. The secondary objective was to identify factors associated with compliance with these recommendations. METHODS: A retrospective cohort study was conducted from January 1, 2016 to December 31, 2016 of all patients who presented to the IWK Health Centre with suspected preterm labour. Inclusion criteria included symptoms of preterm labour prior to 370 weeks gestation, singleton or multiple pregnancy, and established fetal wellbeing. Exclusion criteria included severe fetal anomaly, contraindications to tocolysis, transfer from community hospital, or inadequate documentation. Provider compliance was evaluated to determine: 1) whether the test was performed for appropriate indications according to provincial fFN guidelines; 2) whether fFN results were appropriately being used to inform patient care. Logistic regression was used to determine factors associated with compliance. RESULTS: A total of 528 patients presented with symptoms of preterm labour. The overall compliance with testing recommendations was 76.1%. Compliance for patients who met criteria for fFN testing was 73%, and compliance for those not meeting criteria was 76.4%. Of patients with a negative fFN result, 85.3% were appropriately discharged home without intervention. Gestational age, time of day, and non-obstetrician provider type were found to be associated with compliance. CONCLUSION: Despite regional and national guidelines, this study demonstrates a compliance rate of 76% in our centre, indicating a gap in provider knowledge regarding proper use and interpretation of fFN. Non-obstetrician provider type was associated with decreased compliance.

Prioritizing Maternal Sepsis: National Adoption of an Obstetric Early Warning System to Prevent Morbidity and Mortality.

Sepsis is one of the leading causes of maternal morbidity and mortality. Analyses have determined that delays in early recognition and prompt initiation of appropriate management are key contributing factors in maternal sepsis deaths. Recent cases of sepsis-related maternal morbidity and mortality across Canada have highlighted the urgent need for a national standardized approach to the detection and treatment of maternal sepsis. The SOGC has established a national multidisciplinary maternal sepsis task force to address this priority. The adoption of a national modified obstetric early warning system (MEOWS) is recommended as a key first step. This early warning scoring (EWS) system will facilitate early detection of maternal clinical deterioration and mandate timely escalation of care appropriate for the severity of illness. There is currently limited use of EWSs in Canada. Introducing a national EWS and a standardized maternal sepsis management guideline provides a tremendous opportunity to improve maternal care. A standardized approach will facilitate future evidence-based evaluation and refinement of the tool, and enable the reduction of preventable maternal morbidity and mortality from sepsis, as well as all causes duplicated.

Oral misoprostol, low dose vaginal misoprostol, and vaginal dinoprostone for labor induction: Randomized controlled trial.

OBJECTIVE: To compare effectiveness and safety of oral misoprostol (50 µg every four hours as needed), low dose vaginal misoprostol (25 to 50 µg every six hours as needed), and our established dinoprostone vaginal gel (one to two mg every six hours as needed) induction. MATERIALS AND METHODS: Consenting women with a live term single cephalic fetus for indicated labor induction were randomized (3N = 511). Prior uterine surgery or non-reassuring fetal surveillance were exclusions. Concealed computer generated randomization was stratified and blocked. Newborns were assessed by a team unaware of group assignment. The primary outcome was time from induction at randomization to vaginal birth for initial parametric analysis. Sample size was based on mean difference of 240 minutes with α2 = 0.05 and power 95%. Non-parametric analysis was also pre-specified ranking cesareans as longest vaginal births. RESULTS: Enrollment was from April 1999 to December 2000. Demographics were similar across groups. Analysis was by intent to treat, with no loss to follow up. Mean time (±SD) to vaginal birth was 1356 (±1033) minutes for oral misoprostol, 1530 (±3249) minutes for vaginal misoprostol, and 1208 (±613) minutes for vaginal dinoprostone (P = 0.46, ANOVA). Median times to vaginal birth were 1571, 1339, and 1451 minutes respectively (P = 0.46, Kruskal-Wallis). Vaginal births occurred within 24 hours in 44.9, 53.5 and 47.7% respectively (P = 0.27, χ2). There were no significant differences in Kaplan Meier survival analyses, cesareans, adverse effects, or maternal satisfaction. The newborn who met birth asphyxia criteria received vaginal misoprostol, as did. all three other newborns with cord artery pH<7.0 (P = 0.04, Fisher Exact). CONCLUSION: There was no significant difference in effectiveness of the three groups. Profound newborn acidemia, though infrequent, occurred only with low dose vaginal misoprostol.

Optimal Timing of Prenatal Ultrasound in Predicting Birth Weight in Diabetic Pregnancies.

OBJECTIVE: This study sought to determine the optimal timing of ultrasound in the third trimester to predict birth weight accurately in diabetic women with a singleton pregnancy. METHODS: A retrospective cohort study of all diabetic women with a singleton pregnancy treated in Halifax, Nova Scotia, was performed. Estimated fetal weight was derived from ultrasound measures using the Hadlock2 equation. The Mongelli equation was used to predict birth weight. The association between gestational age at ultrasound and accuracy of predicted birth weight was assessed, with accuracy as a continuous variable representing the difference between predicted and actual birth weight and as a categorical variable (with four gestational age categories) representing whether predicted birth weight was within, over, or under 250 g of actual birth weight RESULTS: The cohort of 943 women comprised 121 (12.8%) with type 1 diabetes, 111 (11.7%) with type 2 diabetes, and 711 (75.4%) with gestational diabetes. Ultrasound scans performed at term were the most accurate in predicting birth weight. At this gestational age, the mean difference between predicted and actual birth weight was -30 g (95% confidence interval -109 to -48). After adjusting for maternal body mass index, age, smoking, type of diabetes, and interval between ultrasound examination and delivery, accuracy improved as gestational age at ultrasound increased (P = 0.005). The odds of underpredicting or overpredicting birth weight were not significantly affected by the timing of the ultrasound examination. CONCLUSION: Because the predictive accuracy of ultrasound prediction of birth weight improves with gestational age, fetal growth assessment at term is recommended to aid with delivery planning in women with diabetes.

Examining the provisional guidelines for weight gain in twin pregnancies: a retrospective cohort study.

BACKGROUND: Weight gain during pregnancy has an important impact on maternal and neonatal health. Unlike the Institute of Medicine (IOM) recommendations for weight gain in singleton pregnancies, those for twin gestations are termed "provisional", as they are based on limited data. The objectives of this study were to determine the neonatal and maternal outcomes associated with gaining weight below, within and above the IOM provisional guidelines on gestational weight gain in twin pregnancies, and additionally, to explore ranges of gestational weight gain among women who delivered twins at the recommended gestational age and birth weight, and those who did not. METHODS: A retrospective cohort study of women who gave birth to twins at ≥20 weeks gestation, with a birth weight ≥ 500 g was conducted in Nova Scotia, Canada (2003-2014). Our primary outcome of interest was small for gestational age (<10th percentile). In order to account for gestational age at delivery, weekly rates of 2nd and 3rd trimester weight gain were used to categorize women as gaining below, within, or above guidelines. We performed traditional regression analyses for maternal outcomes, and to account for the correlated nature of the neonatal outcomes in twins, we used generalized estimating equations (GEE). RESULTS: A total of 1482 twins and 741 mothers were included, of whom 27%, 43%, and 30% gained below, within, and above guidelines, respectively. The incidence of small for gestational age in these three groups was 30%, 21%, and 20%, respectively, and relative to gaining within guidelines, the adjusted odds ratios were 1.44 (95% CI 1.01-2.06) for gaining below and 0.92 (95% CI 0.62-1.36) for gaining above. The gestational weight gain in women who delivered twins at 37-42 weeks with average birth weight ≥ 2500 g and those who delivered twins outside of the recommend ranges were comparable to each other and the IOM recommendations. CONCLUSIONS: While gestational weight gain below guidelines for twins was associated with some adverse neonatal outcomes, additional research exploring alternate ranges of gestational weight gain in twin pregnancies is warranted, in order to optimize neonatal and maternal outcomes.

Gestational Weight Gain and Interpregnancy Weight Change in Adolescent Mothers.

STUDY OBJECTIVE: To examine the association between gestational weight gain (GWG) and interpregnancy weight change (IPWC) in adolescent mothers (younger than 20 years), and to determine if this association differs from adult women (aged 20-35 years). DESIGN: Retrospective cohort study. SETTING AND PARTICIPANTS: We included 3055 adolescents and 17,090 adult women with singleton pregnancies recorded in the Nova Scotia Atlee Perinatal Database with a subsequent pregnancy occurring between 2003 and 2014. INTERVENTIONS AND MAIN OUTCOME MEASURES: GWG in the first pregnancy was categorized as below, within, or above the current Institute of Medicine recommendations. IPWC was defined as the difference between the prepregnancy weights of the 2 pregnancies. Analyses were adjusted for parity, body mass index in the first pregnancy, and time between pregnancies. RESULTS: Relative to adolescents with GWG within the recommendations, those who gained below had a 2.7 kg (95% confidence interval [CI], 1.4-3.9) lower mean IPWC whereas those who gained above had a 4.2 kg (95% CI, 3.3-5.1) higher mean IPWC. Smaller differences in IPWC between GWG categories were observed in adult women; relative to those with GWG within the recommendations, adults who gained below had a 1.3 kg (95% CI, 0.9-1.7) lower mean IPWC and those who gained above had a 2.9 kg (95% CI, 2.6-3.2) higher mean IPWC. CONCLUSION: Mean IPWC differed across GWG categories and the differences were greater in adolescents than in adult women. This difference should be considered when assessing whether specific GWG recommendations are needed for adolescents.

Determinants of vitamin D status in pregnant women and neonates.

OBJECTIVES: Evidence suggests a beneficial effect of vitamin D on perinatal health; however, low vitamin D status is prevalent in pregnant women and neonates. The objective was to determine factors that are associated with vitamin D status of mothers in early pregnancy and neonates. METHODS: The study comprised 1,635 pregnant women from Quebec City and Halifax, Canada, 2002-2010. Vitamin D status was based on the concentration of 25-hydroxy-vitamin D [25(OH)D] determined with a chemiluminescence immunoassay in maternal sera collected at a median of 15 weeks' gestation and in neonatal cord sera at delivery. A questionnaire with information on potential determinants was completed midpregnancy. RESULTS: A total of 44.8% of mothers and 24.4% of neonates had 25(OH)D concentrations <50 nmol/L. Adjusted mean (95% confidence interval) maternal 25(OH)D levels were higher in summer than in winter by 16.1 nmol/L (13.6-18.7), and in those in the highest versus the lowest category of education by 6.1 nmol/L (0.5-11.8), in BMI <25 kg/m2 versus BMI ≥35 kg/m2 by 8.2 nmol/L (4.0-12.3), and in the highest versus the lowest physical activity category by up to 9.5 nmol/L (2.9-16.1). Determinants of neonatal 25(OH)D levels were similar but also included maternal age, dairy intake, supplement use and 25(OH)D level. CONCLUSION: This study suggests that vitamin D status of pregnant women and/or neonates might be improved through supplementation, adequate dairy intake, a move towards a healthy pre-pregnancy body weight, and participation in physical activity. Controlled studies are needed to determine the effectiveness of interventions aimed at these factors.

Vitamin D Status and Gestational Diabetes: Effect of Smoking Status during Pregnancy.

BACKGROUND: Vitamin D status, as measured by serum 25-hydroxyvitamin D (25(OH)D), has been shown in some studies to be inversely associated with gestational diabetes risk. Recently, it has been suggested that maternal smoking status may modify this relationship. We explored the association between 25(OH)D concentration and gestational diabetes and determined if there was an interaction between smoking and 25(OH)D. METHODS: A nested case-control study was conducted in Halifax, Nova Scotia and Quebec City, Quebec. Women were recruited before 20 weeks gestation and 25(OH)D was measured. Cases were women who developed gestational diabetes and controls were frequency matched to cases on study site, gestational age at blood draw, and season and year of blood draw. Logistic regression models estimated adjusted odds ratios (aOR) and 95% confidence intervals (CI). Models were tested for multiplicative and additive interaction, which was estimated by relative excess risk due to interaction (RERI). RESULTS: The study included 395 gestational diabetes cases and 1925 controls. Women who smoked during pregnancy and had 25(OH)D concentrations <30 nmol/L had an aOR = 3.73 [95% CI 1.95, 7.14] compared to non-smokers with 25(OH)D concentrations ≥50 nmol/L. Additive interaction was detected between smoking status and 25(OH)D [RERI = 2.44, 95% CI 0.03, 4.85]. CONCLUSION: Our study supports the inverse association of vitamin D status with gestational diabetes risk, particularly among women who smoke during pregnancy. More research is needed to confirm this finding and, if confirmed, to determine the mechanism by which the combined effect of smoking and low vitamin D status increases the risk of developing gestational diabetes.

Twin Birth Study: 2-year neurodevelopmental follow-up of the randomized trial of planned cesarean or planned vaginal delivery for twin pregnancy.

BACKGROUND: The Twin Birth Study randomized women with uncomplicated pregnancies, between 32(0/7)-38(6/7) weeks' gestation where the first twin was in cephalic presentation, to a policy of either a planned cesarean or planned vaginal delivery. The primary analysis showed that planned cesarean delivery did not increase or decrease the risk of fetal/neonatal death or serious neonatal morbidity as compared with planned vaginal delivery. OBJECTIVE: This study presents the secondary outcome of death or neurodevelopmental delay at 2 years of age. STUDY DESIGN: A total of 4603 children from the initial cohort of 5565 fetuses/infants (83%) contributed to the outcome of death or neurodevelopmental delay. Surviving children were screened using the Ages and Stages Questionnaire with abnormal scores validated by a clinical neurodevelopmental assessment. The effect of planned cesarean vs planned vaginal delivery on death or neurodevelopmental delay was quantified using a logistic model to control for stratification variables and using generalized estimating equations to account for the nonindependence of twin births. RESULTS: Baseline maternal, pregnancy, and infant characteristics were similar. Mean age at assessment was 26 months. There was no significant difference in the outcome of death or neurodevelopmental delay: 5.99% in the planned cesarean vs 5.83% in the planned vaginal delivery group (odds ratio, 1.04; 95% confidence interval, 0.77-1.41; P = .79). CONCLUSION: A policy of planned cesarean delivery provides no benefit to children at 2 years of age compared with a policy of planned vaginal delivery in uncomplicated twin pregnancies between 32(0/7)-38(6/7)weeks' gestation where the first twin is in cephalic presentation.

Cord blood vitamin D status and neonatal outcomes in a birth cohort in Quebec, Canada.

PURPOSE: Some evidence suggests that low maternal vitamin D status adversely affects perinatal health but few studies have examined cord blood vitamin D status. This project aimed to determine the association between the cord blood concentration of 25-hydroxyvitamin D [25(OH)D] and neonatal outcomes. METHODS: A nested case-control study was conducted in Quebec City, Canada from 2005 to 2010. Included were 83 cases of low birthweight (LBW; <2500 g), 301 cases of small for gestational age (SGA; <10th percentile), 223 cases of preterm birth (PTB; <37 weeks' gestation), and 1027 controls. Levels of 25(OH)D were determined by chemiluminescence immunoassay. Adjusted odds ratios (OR) and 95 % confidence intervals (CI) were estimated with logistic regression. RESULTS: Cord blood [25(OH)D] <50 nmol/L was associated with a lower risk of LBW compared to [25(OH)D] ≥75 nmol/L (OR 0.47 95 % CI 0.23-0.97). For 25(OH)D levels 50-75 nmol/L, a significant association was not demonstrated (OR 0.58, 95 % CI 0.34-1.01). No significant associations were observed between [25(OH)D] and either SGA or PTB after adjustment. CONCLUSIONS: Although our findings suggest that [25(OH)D] <50 nmol/L is associated with reduced risk of having a LBW infant, prenatal vitamin D recommendations require an examination of the literature that considers the full spectrum of maternal and neonatal outcomes.

An Algorithm for Predicting Neonatal Mortality in Threatened Very Preterm Birth.

OBJECTIVE: To develop a prediction model for neonatal mortality using information readily available in the antenatal period. METHODS: A multiple logistic regression model of a complete population-based geographically defined cohort of very preterm infants of 23+0 to 30+6 weeks' gestation was used to identify antenatal factors which were predictive of mortality in this population. Infants lt; 23 weeks and those with major anomalies were excluded. RESULTS: Between 1996 and 2012, 1240 live born infants lt; 31 weeks' gestation were born to women residing in Nova Scotia. Decreasing gestational age strongly predicted an increased mortality rate. Other factors significantly contributing to increased mortality included classification as small for gestational age, oligohydramnios, maternal psychiatric disorders, antenatal antibiotic therapy, and monochorionic twins. Reduced neonatal mortality was associated with antenatal use of antihypertensive agents and use of corticosteroids of any duration of therapy given at least 24 hours before delivery. An algorithm was developed to estimate the risk of mortality without the need for a calculator. CONCLUSION: Prediction of the probability of neonatal mortality is influenced by maternal and fetal factors. An algorithm to estimate the risk of mortality facilitates counselling and informs shared decision making regarding obstetric management.

Objectif : Élaborer un modèle prédictif en ce qui concerne la mortalité néonatale au moyen de renseignements faciles à obtenir au cours de la période prénatale. Méthodes : Nous avons eu recours au modèle de régression logistique multiple d'une cohorte exhaustive, populationnelle et définie géographiquement de nouveau-nés très prématurés (âge gestationnel : de 23+0 à 30+6 semaines) pour identifier les facteurs prénataux permettant de prédire la mortalité au sein de cette population. Les nouveau-nés dont l'âge gestationnel était inférieur à 23 semaines et ceux qui présentaient des anomalies majeures ont été exclus. Résultats : Entre 1996 et 2012, 1 240 enfants nés vivants à moins de 31 semaines de gestation ont été issus de femmes résidant en Nouvelle-Écosse. La baisse de l'âge gestationnel constituait un facteur solide permettant de prédire une hausse du taux de mortalité. Parmi les autres facteurs contribuant de façon significative à la hausse du taux de mortalité, on trouvait l'hypotrophie fœtale, l'oligohydramnios, les troubles psychiatriques maternels, l'antibiothérapie prénatale et les jumeaux monozygotes. La baisse du taux de mortalité néonatale était associée à l'utilisation prénatale d'antihypertenseurs et à l'utilisation de corticostéroïdes (peu importe la durée du traitement) administrés au moins 24 heures avant l'accouchement. Nous avons élaboré un algorithme pour estimer le risque de mortalité sans avoir recours à une calculatrice. Conclusion : La prévision de la probabilité de la mortalité néonatale est influencée par des facteurs maternels et fœtaux. Le fait de disposer d'un algorithme pour estimer le risque de mortalité facilite le counseling et éclaire le processus décisionnel partagé en ce qui concerne la prise en charge obstétricale.

Umbilical Cord Blood: Counselling, Collection, and Banking.

OBJECTIVE: To review current evidence regarding umbilical cord blood counselling, collection, and banking and to provide guidelines for Canadian health care professionals regarding patient education, informed consent, procedural aspects, and options for cord blood banking in Canada. OPTIONS: Selective or routine collection and banking of umbilical cord blood for future stem cell transplantation for autologous (self) or allogeneic (related or unrelated) treatment of malignant and non-malignant disorders in children and adults. Cord blood can be collected using in utero or ex utero techniques. OUTCOMES: Umbilical cord blood counselling, collection, and banking, education of health care professionals, indications for cord blood collection, short- and long-term risk and benefits, maternal and perinatal morbidity, parental satisfaction, and health care costs. EVIDENCE: Published literature was retrieved through searches of Medline and PubMed beginning in September 2013 using appropriate controlled MeSH vocabulary (fetal blood, pregnancy, transplantation, ethics) and key words (umbilical cord blood, banking, collection, pregnancy, transplantation, ethics, public, private). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. There were no date limits, but results were limited to English or French language materials. Searches were updated on a regular basis and incorporated in the guideline to September 2014. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, and national and international medical specialty societies. VALUES: The quality of evidence in this document was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1). BENEFITS, HARMS, AND COSTS: Umbilical cord blood is a readily available source of hematopoetic stem cells used with increasing frequency as an alternative to bone marrow or peripheral stem cell transplantation to treat malignant and non-malignant conditions in children and adults. There is minimal harm to the mother or newborn provided that priority is given to maternal/newborn safety during childbirth management. Recipients of umbilical cord stem cells may experience graft-versus-host disease, transfer of infection or genetic abnormalities, or therapeutic failure. The financial burden on the health system for public cord blood banking and on families for private cord blood banking is considerable. Recommendations 1. Health care professionals should be well-informed about cord blood collection and storage and about factors that influence the volume, quality, and ability to collect a cord blood unit. (III-A) 2. Health care professionals caring for women and families who choose private umbilical cord blood banking must disclose any financial interests or potential conflicts of interest. (III-A) 3. Pregnant women should be provided with unbiased information about umbilical cord blood banking options, including the benefits and limitations of public and private banks. (III-A) 4. Health care professionals should obtain consent from mothers for the collection of umbilical cord blood prior to the onset of active labour, ideally during the third trimester, with ample time to address any questions. (III-A) 5. Health care professionals must be trained in standardized procedures (ex utero and in utero techniques) for cord blood collection to ensure the sterility and quality of the collected unit. (II-2A) 6. Umbilical cord blood should be collected with the goal of maximizing the content of hematopoietic progenitors through the volume collected. The decision to bank the unit will depend upon specific measures of graft potency. (II-2A) 7. Umbilical cord blood collection must not adversely affect the health of the mother or newborn. Cord blood collection should not interfere with delayed cord clamping. (III-E) 8. Health care professionals should inform pregnant women and their partners of the benefits of delayed cord clamping and of its impact on cord blood collection and banking. (II-2A) 9. Cord blood units collected for public or private banking can be used for biomedical research, provided consent is obtained, when units cannot be banked or when consent for banking is withdrawn. (II-3B) 10. Mothers may be approached to donate cells for biomedical research. Informed consent for research using cord blood should ideally be obtained prior to the onset of active labour or elective Caesarean section following established research ethics guidelines. (II-2A).

Objectif : Analyser les données probantes actuelles sur le counseling, le prélèvement et la mise en banque, en ce qui a trait au sang de cordon ombilical, et fournir des lignes directrices aux professionnels canadiens de la santé en ce qui concerne la sensibilisation des patientes, le consentement éclairé, les aspects techniques et les options pour la mise en banque de sang de cordon au Canada. Options : Prélèvement sélectif ou systématique et mise en banque du sang de cordon ombilical, en vue de futures greffes autologues (chez le patient même) ou allogéniques (lien de parenté ou non) de cellules souches visant la prise en charge de troubles malins et bénins chez les enfants et les adultes. Le sang de cordon peut être prélevé au moyen de techniques in utero ou ex utero. Issues : Counseling, prélèvement et mise en banque en ce qui a trait au sang de cordon ombilical, formation des professionnels de la santé, indications du prélèvement de sang de cordon, risques et avantages à court et à long terme, morbidité maternelle et périnatale, satisfaction parentale et coûts de santé. Résultats : La littérature publiée a été récupérée par l'intermédiaire de recherches menées dans Medline et PubMed à partir de septembre 2013, au moyen d'un vocabulaire contrôlé (p. ex. « fetal blood ¼, « pregnancy ¼, « transplantation ¼, « ethics ¼) et de mots clés (p. ex. « umbilical cord blood ¼, « banking ¼, « collection ¼, « pregnancy ¼, « transplantation ¼, « ethics ¼, « public ¼, « private ¼) MeSH appropriés. Les résultats ont été restreints aux analyses systématiques, aux études observationnelles et aux essais comparatifs randomisés / essais cliniques comparatifs. Aucune limite n'a été imposée en matière de date, mais les résultats ont été limités aux articles publiés en anglais ou en français. Les recherches ont été mises à jour de façon régulière et intégrées à la directive clinique jusqu'en septembre 2014. La littérature grise (non publiée) a été identifiée par l'intermédiaire de recherches menées dans les sites Web d'organismes s'intéressant à l'évaluation des technologies dans le domaine de la santé et d'organismes connexes, dans des collections de directives cliniques, dans des registres d'essais cliniques et auprès de sociétés de spécialité médicale nationales et internationales. Valeurs : La qualité des résultats a été évaluée au moyen des critères décrits dans le rapport du Groupe d'étude canadien sur les soins de santé préventifs (Tableau). Avantages, désavantages et coûts : Le sang de cordon ombilical constitue une source facile à obtenir de cellules souches hématopoïétiques, lesquelles sont de plus en plus utilisées, à titre de solution de rechange à la moelle osseuse ou aux cellules souches périphériques, pour la greffe visant la prise en charge de pathologies malignes et bénignes chez les enfants et les adultes. Les désavantages pour la mère ou le nouveau-né sont minimes puisque la priorité est accordée à la sûreté maternelle / néonatale pendant la prise en charge de l'accouchement. Les personnes qui reçoivent une greffe de cellules souches issues de sang de cordon ombilical pourraient en venir à connaître la maladie du greffon contre l'hôte, le transfert d'une infection ou d'anomalies génétiques ou l'échec du traitement. Le fardeau financier que doivent assumer le système de soins de santé (dans le cas des banques de sang de cordon ombilical publiques) et les familles (pour la mise en banque du sang de cordon ombilical par des entreprises privées) est considérable. Recommandations 1. Les professionnels de la santé devraient être bien renseignés au sujet du prélèvement et de la conservation du sang de cordon ombilical, ainsi qu'en ce qui concerne les facteurs qui influencent tant le volume et la qualité du sang de cordon ombilical prélevé que la capacité même de prélever une unité de sang de cordon ombilical. (III-A) 2. Les professionnels de la santé qui offrent des soins aux femmes et aux familles qui choisissent d'avoir recours aux services de banques privées de sang de cordon ombilical doivent leur divulguer tout intérêt financier dans de telles banques ou tout conflit d'intérêt potentiel. (III-A) 3. Les femmes enceintes devraient se voir offrir des renseignements objectifs au sujet de leurs options en ce qui concerne la mise en banque du sang de cordon ombilical, y compris au sujet des avantages et des limites des banques publiques et des banques privées. (III-A) 4. Les professionnels de la santé devraient obtenir le consentement de la mère, en ce qui concerne le prélèvement de sang de cordon ombilical, avant le début du travail actif (idéalement, au cours du troisième trimestre), en s'assurant de pouvoir disposer de suffisamment de temps pour répondre aux questions. (III-A) 5. Les professionnels de la santé doivent bénéficier d'une formation en ce qui concerne les interventions standardisées de prélèvement de sang de cordon ombilical (techniques ex utero et in utero) pour assurer la stérilité et la qualité de l'unité prélevée. (II-2A) 6. Le prélèvement de sang de cordon ombilical devrait avoir pour objectif de maximiser la teneur en cellules progénitrices hématopoïétiques, ce que permet la maximisation du volume de sang prélevé. La décision quant à la mise ou non en banque de l'unité prélevée dépend de mesures particulières de la greffabilité de celle-ci. (II-2A) 7. Le prélèvement du sang de cordon ombilical ne doit pas exercer d'effets indésirables sur la santé de la mère ou du nouveau-né. Il ne devrait également pas nuire au clampage différé du cordon. (III-E) 8. Les professionnels de la santé devraient aviser les femmes enceintes et leur partenaire des avantages du clampage différé du cordon et des effets que celui-ci exerce sur le prélèvement et la mise en banque du sang de cordon ombilical. (II-2A) 9. Les unités de sang de cordon ombilical destinées à des banques publiques ou privées peuvent être utilisées aux fins de la recherche biomédicale lorsqu'elles ne répondent pas aux critères de la mise en banque ou lorsque le consentement à leur mise en banque en vient à être retiré (pour autant que le consentement ait d'abord été obtenu). (II-3B) 10. Les mères pourraient être conviées à faire un don de cellules à des fins de recherche biomédicale. Le consentement éclairé, quant à l'utilisation de sang de cordon ombilical à des fins de recherche, devrait idéalement être obtenu avant le début du travail actif ou la tenue d'une césarienne planifiée, conformément aux lignes directrices établies en matière d'éthique de la recherche. (II-2A).

Vitamin D status in early pregnancy and risk of preeclampsia.

OBJECTIVE: We sought to examine the association between maternal serum 25-hydroxyvitamin D (25[OH]D) concentration in early pregnancy and the subsequent diagnosis of preeclampsia (PE). STUDY DESIGN: This was a nested case-control study from 2 prospective Canadian cohorts conducted in Quebec City, Quebec, and Halifax, Nova Scotia, from 2002 through 2010. Participants were pregnant women (n = 169 cases with PE and 1975 controls). Maternal serum was drawn <20 weeks of gestation, and 25(OH)D measurement was performed. Cases were ascertained from medical records. Logistic regression analysis was used to estimate adjusted odds ratios with 95% confidence intervals. RESULTS: Women who developed PE had a significantly lower 25(OH)D concentration at a mean gestational age of 14 weeks compared with women in the control group (mean ± SD 25[OH]D 47.2 ± 17.7 vs 52.3 ± 17.2 nmol/L, P < .0001). Women with 25(OH)D <30 nmol/L compared to those with at least 50 nmol/L had a greater risk of developing PE (adjusted odds ratio, 2.23; 95% confidence interval, 1.29-3.83) after adjustment for prepregnancy body mass index, maternal age, smoking, parity, season and year of blood collection, gestational week at blood collection, and cohort site. Exploratory analysis with cubic splines demonstrated a dose-response relationship between maternal 25(OH)D and risk of PE, up to levels around 50 nmol/L, where the association appeared to plateau. CONCLUSION: Maternal vitamin D deficiency early in pregnancy defined as 25(OH)D <30 nmol/L may be an independent risk factor for PE. The relevance of vitamin D supplementation for women of childbearing age should be explored as a strategy for reducing PE and for promoting a healthier pregnancy.

The association between physical activity and maternal and neonatal outcomes: a prospective cohort.

Some evidence, but not enough to be conclusive, suggests that physical activity in pregnancy reduces the risk of perinatal complications. Our objective was to examine if physical activity in the year before pregnancy and in the first half of pregnancy is associated with maternal and neonatal outcomes. Associations between physical activity and maternal and neonatal outcomes were examined in a prospective cohort (n = 1,749) in Halifax, Canada. The Kaiser Physical Activity Survey, completed at approximately 20 weeks' gestation, requested information regarding physical activity during the year before the pregnancy and the first 20 weeks of pregnancy. Outcomes were assessed by medical chart review. Multiple logistic regression was used to estimate odds ratios (OR) with 95 % confidence intervals (CI). Women with prepregnancy physical activity levels in the middle and highest tertiles were more likely to have high gestational weight gain relative to women in the lowest tertile [OR (CI): 1.40 (1.06-1.85) and 1.57 (1.18-2.09), respectively]. Higher physical activity in the first half of pregnancy decreased the odds of delivering a macrosomic infant (p trend = 0.005). Associations were not observed between total physical activity and gestational diabetes, gestational hypertension, pre-eclampsia, preterm birth, and low birth weight. Physical activity before, but not in the first half of pregnancy, is associated with high gestational weight gain. Physical activity in the first half of pregnancy may reduce the occurrence of macrosomia without affecting preterm birth or low birth weight.