Angela Vinturache

Pre-pregnancy Body Mass Index (BMI) and delivery outcomes in a Canadian population

BackgroundWorldwide there has been a dramatic increase in the prevalence of overweight and obesity in women of childbearing age. Growing evidence suggests that maternal overweight and obesity is associated with poor maternal and perinatal outcomes. This study evaluated the impact of maternal pre-pregnancy overweight and obesity on pregnancy, labour and delivery outcomes in a cohort of women with term, singleton pregnancies cared for by family physicians in community based practices.MethodsThis study is a secondary analysis of the All Our Babies Cohort, a prospective, community-based pregnancy cohort in Calgary, Alberta. Maternal self-reported data on height and pre-pregnancy weight from term, singleton, cephalic pregnancies (n = 1996) were linked to clinical data on pregnancy and birth events retrieved from electronic health records. Descriptive and bivariate regression analysis were used to compare pregnancy and birth outcomes between women categorized as normal weight, overweight and obese based on the pre-pregnancy BMI. Multinomial regression analysis stratified by type of labour onset examined the association between pre-pregnancy BMI and mode of delivery controlling for maternal age, pre-existent health conditions, parity, fertility treatments, history of C-section and pregnancy complications.ResultsThe cohort consisted of 65.8% normal weight, 23.6% overweight and 10.6% obese women. Women with increased pre-pregnancy BMI were more likely to develop pregnancy complications such as preeclampsia (OR 3.5, CI 2.0-4.6 for overweight; OR 5.3, CI 3.3-8.5 for obese) and gestational diabetes (OR 3.0, CI 1.8-5.0 for overweight; OR 6.5, CI 3.7-11.2 for obese) than normal weight women. Spontaneous onset of labour was recorded in 71.2% of women with normal pre-pregnancy BMI, whereas 39.3% of overweight and 49% of obese women had their labour induced. For women with spontaneous labour, pre-pregnancy BMI was not a significant risk factor for mode of delivery, controlling for covariates. Among women with induced labor, obesity was a significant risk factor for delivery by C-section (adjusted OR 2.2; CI 1.2-4.1).ConclusionsEven among women with term, singleton pregnancies obtaining prenatal care in community-based settings, obese women who undergo labour induction are at increased risk of obstetrical interventions at delivery. These findings highlight the importance of tailored maternal care in pregnancy and at delivery of pregnant women with increased BMI in order to improve the outcomes and wellbeing of these women and their children.

Maternal microbiome – A pathway to preterm birth

Despite great medical advances in preventing maternal and infant mortality in the past century, one issue remains unresolved: why do so many women give birth prematurely? A major new field of human microbiome studies has begun to shed light on the impact of microbes (of both the commensal and pathogen varieties) on pregnancy outcomes. Recent advances in next-generation sequencing and metagenomic analysis have revealed that maternal microbiomes at a variety of niches including the oral, vaginal, gut, cervical, and even the placenta itself govern pregnancy outcomes. In this review, we describe how alterations in the microbial biomasses impact preterm birth and we discuss the major research questions concerning the cause and/or interdependent relationships between microbiome, infection, and preterm delivery.

Perinatal outcomes of maternal overweight and obesity in term infants: a population-based cohort study in Canada

The objective of this study was to assess the impact of increased pre-pregnancy maternal body mass index (BMI) on perinatal outcomes in term, singleton pregnancies who received prenatal care in community-based practices. The sample of 1996 infants included in the study was drawn from the All Our Babies Study, a prospective pregnancy cohort from Calgary. Multivariable logistic regression explored the relationship between the main outcomes, infant birth weight, Apgar score, admission to neonatal intensive care (NICU) and newborn duration of hospitalization, and BMI prior to pregnancy. Approximately 10% of the infants were macrosoms, 1.5% had a low Apgar score (<7 at 5 min), 6% were admitted to intensive care and 96% were discharged within 48 h after delivery. Although the infants of overweight and obese women were more likely to have increased birth weight as compared to infants of normal weight women, there were no differences in Apgar score, admission to NICU, or length of postnatal hospital stay among groups. This study suggests that in otherwise healthy term, singleton pregnancies, obesity does not seem to increase the risk of severe fetal impairment, neonatal admission to intensive care or duration of postnatal hospitalization.

Angiotensin type 1 and type 2 receptors during ontogeny: cardiovascular and renal effects

The renin-angiotensin system (RAS) is a major component of cardiovascular and renal homeostasis, maintaining blood pressure and water and electrolyte balance in health and disease. Whilst knowledge regarding the RAS in adult organisms has substantially increased over the last three decades, physiological effects and levels of functioning of the system during the perinatal period are poorly understood. It has been shown, however, that the RAS is subject to remarkable developmental changes that involve all system components, including the main active biologic peptide, angiotensin II (Ang II) and the receptors through which these effects are mediated, type 1 receptors (AT1Rs) and type 2 receptors (AT2Rs). The pattern of developmental changes suggests a relevant physiological role for the RAS in the critical cardio-renal adaptations to life after birth. In adulthood, the majority of the physiological functions of Ang II are mediated by activation of AT1Rs, whilst the roles for AT2Rs are less clear. Although the integrity of the AT1R signalling pathway is a pre-requisite for normal renal development, the physiological effects mediated by A1TRs during ontogeny are not well characterized. Much less is known regarding the roles that AT2Rs may play in regulating cardio-renal homeostasis in the newborn, despite the fact that the RAS appears to be a major player in fetal programming of disease. This article reviews current knowledge regarding the temporal and spatial expression pattern of ATRs during ontogeny, the cardiovascular and renal effects mediated by the ATRs early in life, as well as the clinical relevance for ATRs in the newborn period.

Adherence to Canadian physical activity and sedentary behaviour guidelines among children 2 to 13 years of age.

Active living is relevant for healthy child development and disease prevention. In 2011–2012 new Canadian Physical Activity and Sedentary Behaviour Guidelines were developed for children under four and 5–17 years of age. This cross-sectional study assessed childrens adherence to the national guidelines, using a large sample of Alberta children ages 2–4 and 5–13 years in 2013. The proportions of children achieving the average daily duration of physical activity and screen time recommended were determined, and child and parental predictors of non-achievement were identified. Participants were 631 parent and child dyads. Data were collected by parental reports of physical activity and screen time during weekdays, and analysed using univariate and multivariate techniques (p < 0.05). Logistic regression models were used to examine factors associated with childrens non-achievement of physical activity and screen time recommendations while adjusting for covariates. Sixty-two percent of children aged 2–4 and 26% of children aged 5–13 did not meet physical activity time recommendations, and 64% of children aged 2–4 and 23% of children aged 5–13 exceeded the maximum screen time recommendation. Several associations between parental age and education with non-achievement were observed but associations were not consistent across age groups or behaviours. Among preschoolers, those with middle-age parents were more likely to not achieve physical activity recommendations. Evidence of high non-achievement of the recommendations among children 2–4 years highlights the need for increased programming targeting preschool children. Further research is required to identify modifiable risk factors that may inform future health promotion efforts.

Maternal Whole Blood Gene Expression at 18 and 28 Weeks of Gestation Associated with Spontaneous Preterm Birth in Asymptomatic Women

The heterogeneity of spontaneous preterm birth (SPTB) requires an interdisciplinary approach to determine potential predictive risk factors of early delivery. The aim of this study was to investigate maternal whole blood gene expression profiles associated with spontaneous preterm birth (SPTB, <37 weeks) in asymptomatic pregnant women. The study population was a matched subgroup of women (51 SPTBs, 114 term delivery controls) who participated in the All Our Babies community based cohort in Calgary (n = 1878). Maternal blood at 17–23 (sampling time point 1, T1) and 27–33 weeks of gestation (T2) were collected. Total RNA was extracted and microarray was performed on 326 samples (165 women). Univariate analyses determined significant clinical factors and differential gene expression associated with SPTB. Thirteen genes were validated using qRT-PCR. Three multivariate logistic models were constructed to identify gene expression at T1 (Model A), T2 (Model B), and gene expression fold change from T1 to T2 (Model C) associated with SPTB. All models were adjusted for clinical factors. Model C can predict SPTB with 65% sensitivity and 88% specificity in asymptomatic women after adjusting for history of abortion and anaemia (occurring before T2). Clinical data enhanced the sensitivity of the Models to predict SPTB. In conclusion, clinical factors and whole blood gene expression are associated with SPTB in asymptomatic women. An effective screening tool for SPTB during pregnancy would enable targeted preventive approaches and personalised antenatal care.

Effect of depressive and anxiety symptoms during pregnancy on risk of obstetric interventions.

The effect of prenatal mental health on the risk of obstetric interventions is unclear. The present study examined the associations between depressive and anxiety symptoms in the second and third trimesters and mode of delivery, epidural use and labor induction in a large community‐based pregnancy cohort, in Alberta, Canada.

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 1st and 30th 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.

Do Angiotensin Type 2 Receptors Modulate Haemodynamic Effects of Type 1 Receptors in Conscious Newborn Lambs

Introduction and hypothesis: It was hypothesized that in the immediate newborn period, when the renin–angiotensin system (RAS) is activated, angiotensin type 2 receptors (AT2Rs) buffer the haemodynamic effects of angiotensin type 1 receptors (AT1Rs), as occurs in adult animals when the RAS is activated. Materials and methods: Arterial (systolic, diastolic, and mean) pressures (SAP, DAP, MAP), mean venous pressures (MVP) and renal blood flows (RBF) were measured in conscious, chronically instrumented lambs aged ~1 (8±2 days, N=8) and 6 weeks (41±4 days, N=11). In each animal, measurements were made before and after administration of the selective AT1R antagonist ZD 7155 (experiment one) and the selective AT2R antagonist PD123319 (experiment two) as well as both antagonists, ZD 7155 and PD 123319 (experiment three). Results: Haemodynamic responses to combined inhibition of both AT1Rs and AT2Rs were similar to inhibition of AT1Rs alone: there was a significant decrease in SAP, DAP, and MAP and a significant increase in RBF within minutes of concomitant administration of ZD 7155 and PD 123319 in both age groups. These responses were similar to responses to ZD 7155 alone, whereas PD 123319 alone did not alter any of the measured variables. Conclusions: AT2Rs do not counterbalance the pressor and renal vasoconstrictor effects elicited by activation of AT1Rs in the immediate newborn period. During this time, AT1Rs appear to predominate in eliciting the haemodynamic effects of angiotensin II (ANG II), whereas the role of the upregulated AT2Rs remains elusive.

Biomarkers of spontaneous preterm birth: A systematic review of studies using multiplex analysis

Abstract Objective: Despite decades of research on risk indicators of spontaneous preterm birth (PTB), reliable biomarkers are still not available to screen or diagnose high-risk pregnancies. Several biomarkers in maternal and fetal compartments have been mechanistically linked to PTB, but none of them are reliable predictors of pregnancy outcome. This systematic review was conducted to synthesize the knowledge on PTB biomarkers identified using multiplex analysis. Materials and methods: Three electronic databases (PubMed, EMBASE and Web of Science) were searched for studies in any language reporting the use of multiplex assays for maternal biomarkers associated with PTB published from January 2005 to March 2014. Results: Retrieved citations (3631) were screened, and relevant studies (33) were selected for full-text reading. Ten studies were included in the review. Forty-two PTB-related proteins were reported, and RANTES and IL-10 (three studies) followed by MIP-1β, GM-CSF, Eotaxin, and TNF-RI (two studies) were reported more than once in maternal serum. However, results could not be combined due to heterogeneity in type of sample, study population, assay, and analysis methods. Conclusion: By this systematic review, we conclude that multiplex assays are a potential technological advancement for identifying biomarkers of PTB, although no single or combination of biomarkers could be identified to predict PTB risk.