Shi Wu Wen

Umbilical cord blood levels of perfluoroalkyl acids and polybrominated flame retardants

Perfluoroalkyl acids (PFAAs) and polybrominated diphenyl ethers (PBDEs) are persistent organic pollutants representing two classes of environmental contaminants of toxicological concern, especially for infants. Canadian biomonitoring data on these chemicals are limited. The objectives of this study were to measure PFAAs and PBDEs in umbilical cord blood from approximately 100 hospital deliveries in Ottawa (Ontario, Canada) and examine associations with characteristics of the mother and infant. Geometric means were 1.469 ng/mL for perfluorooctanoate (PFOA) (95% confidence interval of 1.292-1.671 ng/mL), 4.443 ng/mL for perfluorooctane sulfonate (PFOS) (95% CI of 3.735-5.285 ng/mL), 0.359 ng/mL for perfluorononanoic acid (PFNA) (95% CI of 0.318-0.404 ng/mL), and 0.579 ng/mL for perfluorohexanesulfonate (PFHxS) (95% CI of 0.473-0.709 ng/mL). The final multiple regression models indicated that lower gravida, term gestational age, smoking during pregnancy and vaginal delivery were significantly associated with higher levels of PFOS. Similarly, a vaginal delivery was significantly associated with higher PFOA, while weak associations were found with lower gravida and birth weight less than 2500 g. Furthermore, higher PFNA concentrations were significantly associated with older mothers, and vaginal delivery, while weakly associated with term gestational age. Elevated PFHxS concentrations were significantly associated with smoking during pregnancy and lower gravida. Similar to reports from other countries, the preponderant PBDE congener measured in the cord blood was PBDE-47. Questions remain on why various studies have reported conflicting results on the association between PFAAs and birth weight.

Utilization of Health Care Services of Pregnant Women Complicated by Preeclampsia in Ontario

Objective: To assess the utilization of health care services by pregnant women affected by preeclampsia (PE). Design: Population-based study. Setting: Perinatal partnership hospitals in Ontario. Population: Obstetric deliveries in 2005 Canadian province of Ontario (about 95% of births). Methods: For each PE case, four subjects without PE matched by age, parity, plurality, and hospital at childbirth were chosen as the controls. We compared the utilization of intra-partum care services and infant outcomes between the two groups. We also estimated the extra costs to the health care system in Ontario for caesarean delivery and caring of extremely low birth weight infants attributable to PE during the neonatal period and in the first 2 years of life. Main Outcome Measures: Cesarean delivery, hospital stay, extremely low birth weight infants, cost. Results: Of the 120,611 obstetric deliveries included in this analysis, 1240 (1.3%) were diagnosed with PE. Patients with PE and matched controls were similar in maternal age, parity, and other demographic characteristics. Compared with study subjects without PE, those with PE had increased uses of spinal anesthesia, maternal transfer, Cesarean delivery, labour induction, neonatal transfer, newborn resuscitation, longer hospital stay for childbirth, and higher rates of preterm births and low birth weight. The extra costs to the health care system for cesarean delivery and caring of extremely low-birth-weight infants attributable to PE during the neonatal period and in the first 2 years of life in Ontario were

Effect of Folic Acid Supplementation in Pregnancy on Preeclampsia: The Folic Acid Clinical Trial Study

0.5 millions, 3.1 millions, and

Fetal sex, social support, and postpartum depression.

5.1 million per year, respectively, if we use the reported PE rate in this database. Conclusion: PE is associated with substantially increased costs to the health care system.

Higher Cesarean Delivery Rates are Associated with Higher Infant Mortality Rates in Industrialized Countries

Preeclampsia (PE) is hypertension with proteinuria that develops during pregnancy and affects at least 5% of pregnancies. The Effect of Folic Acid Supplementation in Pregnancy on Preeclampsia: the Folic Acid Clinical Trial (FACT) aims to recruit 3,656 high risk women to evaluate a new prevention strategy for PE: supplementation of folic acid throughout pregnancy. Pregnant women with increased risk of developing PE presenting to a trial participating center between 80/7 and 166/7 weeks of gestation are randomized in a 1u2009:u20091 ratio to folic acid 4.0u2009mg or placebo after written consent is obtained. Intent-to-treat population will be analyzed. The FACT study was funded by the Canadian Institutes of Health Research in 2009, and regulatory approval from Health Canada was obtained in 2010. A web-based randomization system and electronic data collection system provide the platform for participating centers to randomize their eligible participants and enter data in real time. To date we have twenty participating Canadian centers, of which eighteen are actively recruiting, and seven participating Australian centers, of which two are actively recruiting. Recruitment in Argentina, UK, Netherlands, Brazil, West Indies, and United States is expected to begin by the second or third quarter of 2013. This trial is registered with NCT01355159.

Chronic Perinatal Pain as a Risk Factor for Postpartum Depression Symptoms in Canadian Women

Objective: To examine the impact of prenatal and postnatal social support on the association between fetal sex and postpartum depression (PPD). Method: We conducted a prospective cohort study in Changsha, China, between February and September 2007. We first compared the sociodemographic and obstetric characteristics, and the prenatal and postnatal social support between women who gave birth to a female infant and those who gave birth to a male infant. We then examined the association between fetal sex and PPD by following logistic regression models: fetal sex as the independent variable; with adjustment for sociodemographic and obstetric factors; with adjustment for sociodemographic, obstetric factors, and prenatal social support; and with adjustment for sociodemographic, obstetric factors, and postnatal social support. Results: Postnatal social support scores were much lower in women who gave birth to a female infant than in those who gave birth to a male infant. The odds ratio of PPD for women who gave birth to a female infant, as compared with those who gave birth to a male infant, was 3.67 (95% CI 2.31 to 5.84). The increased risk of PPD for women who gave birth to a female infant remained after adjustment for sociodemographic and obstetric factors and prenatal social support, but disappeared after adjustment for postnatal social support score. Conclusion: We conclude that increased risk of PPD in Chinese women who give birth to a female infant is caused by lack of social support after childbirth.

Secondary analysis of the use of transdermal nitroglycerin for preterm labor

BACKGROUNDnRecent data indicate that more than half of high-income industrialized countries have a cesarean delivery rate of xa0>xa025 percent, which is higher than the appropriate level considered by most health professionals worldwide.nnnMETHODSnData for 31 high-income industrialized countries in 2010 (or the nearest year) obtained from the World Health Organization, Organization for Economic Cooperation and Development, World Bank, and individual countries were analyzed in this study. We examined the correlation between cesarean delivery rate and infant mortality rate with Pearson correlation coefficient analysis, and examined the independent effect of cesarean delivery on infant mortality with multiple linear regression analyses.nnnRESULTSnThe cesarean delivery and infant mortality rates varied substantially among the included countries: from 15.6 to 50.0 percent and from 1.9 per to 6.8 per 1,000 live births, respectively. Cesarean delivery rates were positively correlated with infant mortality rates (Pearson correlation coefficient: 0.41, pxa0<xa00.05). The association remained after adjustment for maternal age, infant sex, per capita GDP, and the Gini index (pxa0<xa00.03), but disappeared after further adjustment for preterm birth (pxa0=xa00.07). In a sensitivity analysis, the results were not appreciably affected by excluding births at <xa022xa0weeks of gestation, by weighting the data by the number of births in each country, or by excluding data from particular countries with possible measurement issues (USA, Greece).nnnCONCLUSIONSnA higher cesarean delivery rate is associated with higher infant mortality rate among these high-income industrialized countries. One of the mechanisms by which cesarean delivery affects infant mortality is through iatrogenic prematurity.

Effect of folic acid supplementation during pregnancy on gestational hypertension/preeclampsia: A systematic review and meta-analysis

ObjectiveTo examine whether problematic perinatal pain is associated with postpartum depression (PPD) symptoms in a large nationally representative sample of Canadian mothers.MethodsWe conducted a secondary data analysis using the 2006 Canadian Maternity Experiences Survey data (n=5,614). The main exposures of interest were the presence of problematic perinatal pain at three months postpartum, the duration of problematic perinatal pain, and the number of types of perinatal pain (vagina, caesarean incision site, breasts, back, severe headaches) at the time of interview (mean=7.3 months, range 5–14 months). For each exposure, full multivariate logistic regression models as well as six submodels were fitted.ResultsOdds of screening positive for PPD symptoms for respondents reporting problematic perinatal pain in the first three months postpartum were 1.7 (95% CI 1.2-2.5). Compared to respondents without problematic perinatal pain, the odds of PPD symptoms for women reporting problematic perinatal pain at the time of interview was 2.4 (95% CI 1.6-3.6). A dose-response association between the number of types of perinatal pain at the time of interview and PPD symptoms was also observed.ConclusionMothers reporting persistent perinatal pain are at increased risk of developing PPD, and pain control services for these women may be needed.RésuméObjectifExaminer si la douleur périnatale problématique est associée aux symptômes de la dépression postpartum (DPP) dans un échantillon national représentatif de mères canadiennes.MéthodesNous avons effectué une analyse secondaire des données de l’Enquête sur l’expérience de la maternité au Canada de 2006 (n=5 614). Les variables dépendantes étaient la présence de douleurs périnatales problématiques dans les trois premiers mois postpartum, la durée des douleurs périnatales problématiques, ainsi que le nombre de types de douleurs périnatales encore présentes lors de l’entrevue qui a eu lieu en moyenne à 7,3 mois postpartum (étendue: 5 à 14 mois). Un modèle de régression logistique multivariée complet ainsi que six sous-modèles ont été construits pour chacune de ces variables dépendantes.RésultatsLes chances de répondre positivement au dépistage des symptômes de la DPP pour les répondantes ayant déclaré une douleur périnatale problématique étaient de 1,7 (IC 95% 1,2-2,5). Le rapport de cotes pour les femmes souffrant encore de douleurs périnatales problématiques lors de l’entrevue était de 2,4 (IC 95% 1,6-3,6) comparativement aux répondantes ne souffrant pas de douleurs problématiques. Une relation dose-réponse entre le nombre de types de douleurs périnatales et les symptômes de la DPP a également été observée.ConclusionLes mères qui signalent une douleur persistante périnatale ont un risque accru de DPP et pourraient nécessiter des services de contrôle de la douleur.

Serum and red-blood-cell folate demonstrate differential associations with BMI in pregnant women.

OBJECTIVEnThis secondary analysis of a randomized placebo-controlled trial was to hypothesize on mechanisms for the improved neonatal outcomes with the use of nitroglycerin (GTN) for preterm labor.nnnSTUDY DESIGNnWomen in the original trial who delivered at term were excluded. A composite of severe neonatal outcomes, gestational age at delivery, and corticosteroid use in addition to Kaplan-Meier survival analysis to assess time from randomization to delivery were examined.nnnRESULTSnA decrease in composite neonatal outcome (relative risk, 0.21; 95% confidence interval, 0.05-0.81; P = .018) with GTN (n = 39) compared with placebo (n = 38) was primarily due to a 23 day prolongation of pregnancy (P = .019) and a trend (P = .04) toward completing a course of corticosteroids in the subgroup randomized prior to 28 weeks gestation.nnnCONCLUSIONnWe hypothesize that GTN has a gestational age-dependent reduction in neonatal outcomes as a result of pregnancy prolongation and corticosteroid administration.

Antiviral medication use in a cohort of pregnant women during the 2009–2010 influenza pandemic

ABSTRACT Objective: To evaluate the effect of folic acid supplementation during pregnancy on the risk of gestational hypertension/preeclampsia. Methods: A systematic review and meta-analysis were conducted. Medline, Embase, Scopus, and the Web of Science were searched from inception to December 2014. Results: Out of 1224 potentially relevant studies, 13 studies met our inclusion criteria (2 randomized controlled trials (RCTs), 10 cohort studies, and 1 case–control study). The pooled relative risk (RR) and 95% confidence interval (CI) of the two RCTs were 0.62 (0.45–0.87) in the trial arm as compared with the placebo arm. The pooled RR was 0.92 (95% CI: 0.79–1.08) for nine cohort studies with available data on folic acid supplementation in pregnancy and gestational hypertension/preeclampsia. Pooled RR was 0.88 (95% CI: 0.76–1.02) for eight cohort studies with available data on folic acid supplementation and preeclampsia. Conclusion: Whether folic acid supplementation in pregnancy can prevent the occurrence of gestational hypertension/preeclampsia remains uncertain.