Reg Sauve

Maternal age and risk of stillbirth: a systematic review

Background: The number of women who delay childbirth to their late 30s and beyond has increased significantly over the past several decades. Studies regarding the relation between older maternal age and the risk of stillbirth have yielded inconsistent conclusions. In this systematic review we explored whether older maternal age is associated with an increased risk of stillbirth. Methods: We searched MEDLINE, EMBASE and the Cochrane Database of Systematic Reviews for all relevant articles (original studies and systematic reviews) published up to Dec. 31, 2006. We included all cohort and case–control studies that measured the association between maternal age and risk of stillbirth. Two reviewers independently abstracted data from all included studies using a standardized data abstraction form. Methodologic and statistical heterogeneities were reviewed and tested. Results: We identified 913 unique citations, of which 31 retrospective cohort and 6 case–control studies met our inclusion criteria. In 24 (77%) of the 31 cohort studies and all 6 of the case–control studies, we found that greater maternal age was significantly associated with an increased risk of stillbirth; relative risks varied from 1.20 to 4.53 for older versus younger women. In the 14 studies that presented adjusted relative risk, we found no extensive change in the direction or magnitude of the relative risk after adjustment. We did not calculate a pooled relative risk because of the extreme methodologic heterogeneity among the individual studies. Interpretation: Women with advanced maternal age have an increased risk of stillbirth. However, the magnitude and mechanisms of the increased risk are not clear, and prospective studies are warranted.

Risk of maternal postpartum readmission associated with mode of delivery.

OBJECTIVE: To determine whether cesarean and operative vaginal deliveries are associated with an increased risk of maternal rehospitalization compared with spontaneous vaginal delivery. METHODS: A population-based cohort study was conducted by using the Canadian Institute for Health Informations Discharge Abstract Database between 1997/1998 and 2000/2001, which included 900,108 women aged 15–44 years with singleton live births (after excluding several selected obstetric conditions). RESULTS: A total of 16,404 women (1.8%) were rehospitalized within 60 days after initial discharge. Compared with spontaneous vaginal delivery (rate 1.5%), cesarean delivery was associated with a significantly increased risk of postpartum readmission (rate 2.7%, odds ratio [OR] 1.9, 95% confidence interval [CI] 1.8–1.9); ie, there was 1 excess postpartum readmission per 75 cesarean deliveries. Diagnoses associated with significantly increased risks of readmission after cesarean delivery (compared with spontaneous vaginal delivery) included pelvic injury/wounds (rate 0.86% versus 0.06%, OR 13.4, 95% CI 12.0–15.0), obstetric complications (rate 0.23% versus 0.08%, OR 3.0, 95% CI 2.6–3.5), venous disorders and thromboembolism (rate 0.07% versus 0.03%, OR 2.7, 95% CI 2.1–3.4), and major puerperal infection (rate 0.45% versus 0.27%, OR 1.8, 95% CI 1.6–1.9). Women delivered by forceps or vacuum were also at an increased risk of readmission (rates 2.2% and 1.8% versus 1.5%; OR forceps: 1.4, 95% CI 1.3–1.5; OR vacuum: 1.2, 95% CI 1.2–1.3, respectively). Higher readmission rates after operative vaginal delivery were due to pelvic injury/wounds, genitourinary conditions, obstetric complications, postpartum hemorrhage, and major puerperal infection. CONCLUSION: Compared with spontaneous vaginal delivery, cesarean delivery, and operative vaginal delivery increase the risk of maternal postpartum readmission. LEVEL OF EVIDENCE: II-2

Breastfeeding Rates and Hospital Breastfeeding Practices in Canada: A National Survey of Women

BACKGROUND The Baby-Friendly Hospital Initiative was launched by the World Health Organization and UNICEF in 1989 to promote, protect, and support breastfeeding worldwide. The objective of this study was to report breastfeeding rates and adherence to the Baby Friendly Hospital Initiative of the World Health Organization and UNICEF in Canada, as reported by participants in the Maternity Experiences Survey of the Canadian Perinatal Surveillance System. METHODS Eligible women (n = 8,244) were identified from a randomly selected sample of infants born 3 months before the May 2006 Canadian Census, and stratified by province or territory. Birth mothers living with their infants at the time of interview were invited to participate in a computer-assisted telephone interview conducted by Statistics Canada on behalf of the Public Health Agency of Canada. Interviews took approximately 45 minutes and were completed when infants were between 5 and 10 months old (between 9 and 14 months in the territories). Completed responses were obtained from 6,421 women (78% response rate). Nineteen of 309 questions concerned early mother-infant contact and breastfeeding practices. RESULTS Breastfeeding intention (90.0%) and initiation (90.3%) rates were high, although exclusive breastfeeding rates at 6 months after birth (14.4%) were lower than desirable. The findings suggested a low adherence to several best practices advocated by the Baby-Friendly Hospital Initiative. CONCLUSION Although breastfeeding initiation rates were relatively high in Canada, exclusive breastfeeding duration fell short of globally recommended standards.

Reconciling the high rates of preterm and postterm birth in the United States.

OBJECTIVE: Preterm and postterm birth rates are substantially higher in the United States than in Canada and other industrialized countries, although relative mortality at preterm compared with term gestation is considerably lower. We attempted to explain these differences based on differences in the method of gestational age estimation. METHODS: We used information on all live births in the United States and Canada for 1995–2002 and on singleton births and perinatal deaths for 1996–1999. Gestational age in Canada was based on the clinical estimate, whereas in the United States both menstrual-based and clinical estimates were used. RESULTS: In 2002, preterm (12.3%) and postterm birth (6.6%) rates in the United States were far higher than in Canada (7.6% and 1.0%, respectively) when U.S. rates were based on menstrual dates. Differences were reduced or abolished when U.S. rates were based on the clinical estimate of gestation (10.1% and 1.0%, respectively). In Canada, the rate ratio for perinatal death at preterm compared with term gestation was 27.8 (95% confidence interval [CI] 26.3–29.3), similar to that in the United States when gestation was based on the clinical estimate (rate ratio 26.5, 95% CI 26.1–26.9, P value for difference in rate ratios=.06) but not when based on menstrual dates (rate ratio 18.9, 95% CI 18.7–19.2, P<.001). CONCLUSION: Menstrual dates in U.S. data misclassify gestational duration and overestimate both preterm and postterm birth rates. For international comparisons, gestational age in the United States should be based on the clinical estimate. Level of Evidence: II

Use of simulation-based education to improve outcomes of central venous catheterization: a systematic review and meta-analysis.

Purpose Central venous catheterization (CVC) is increasingly taught by simulation. The authors reviewed the literature on the effects of simulation training in CVC on learner and clinical outcomes. Method The authors searched computerized databases (1950 to May 2010), reference lists, and considered studies with a control group (without simulation education intervention). Two independent assessors reviewed the retrieved citations. Independent data abstraction was performed on study design, study quality score, learner characteristics, sample size, components of interventional curriculum, outcomes assessed, and method of assessment. Learner outcomes included performance measures on simulators, knowledge, and confidence. Patient outcomes included number of needle passes, arterial puncture, pneumothorax, and catheter-related infections. Results Twenty studies were identified. Simulation-based education was associated with significant improvements in learner outcomes: performance on simulators (standardized mean difference [SMD] 0.60 [95% CI 0.45 to 0.76]), knowledge (SMD 0.60 [95% CI 0.35 to 0.84]), and confidence (SMD 0.41 [95% CI 0.30 to 0.53] for studies with single-group pretest and posttest design; SMD 0.52 (95% CI 0.23 to 0.81) for studies with nonrandomized, two-group design). Furthermore, simulation-based education was associated with improved patient outcomes, including fewer needle passes (SMD −0.58 [95% CI −0.95 to −0.20]), and pneumothorax (relative risk 0.62 [95% CI 0.40 to 0.97]), for studies with nonrandomized, two-group design. However, simulation-based training was not associated with a significant reduction in risk of either arterial puncture or catheter-related infections. Conclusions Despite some limitations in the literature reviewed, evidence suggests that simulation-based education for CVC provides benefits in learner and select clinical outcomes.

Influence of definition based versus pragmatic birth registration on international comparisons of perinatal and infant mortality: population based retrospective study

Objectives To examine variations in the registration of extremely low birthweight and early gestation births and to assess their effect on perinatal and infant mortality rankings of industrialised countries. Design Retrospective population based study. Setting Australia, Canada, European countries, and the United States for 2004; Australia, Canada, and New Zealand for 2007. Population National data on live births and on fetal, neonatal, and infant deaths. Main outcome measures Reported proportions of live births with birth weight/gestational age of less than 500 g, less than 1000 g, less than 24 weeks, and less than 28 weeks; crude rates of fetal, neonatal, and infant mortality; mortality rates calculated after exclusion of births under 500 g, under 1000 g, less than 24 weeks, and less than 28 weeks. Results The proportion of live births under 500 g varied widely from less than 1 per 10 000 live births in Belgium and Ireland to 10.8 per 10 000 live births in Canada and 16.9 in the United States. Neonatal deaths under 500 g, as a proportion of all neonatal deaths, also ranged from less than 1% in countries such as Luxembourg and Malta to 29.6% in Canada and 31.1% in the United States. Rankings of countries based on crude fetal, neonatal, and infant mortality rates differed substantially from rankings based on rates calculated after exclusion of births with a birth weight of less than 1000 g or a gestational age of less than 28 weeks. Conclusions International differences in reported rates of extremely low birthweight and very early gestation births probably reflect variations in registration of births and compromise the validity of international rankings of perinatal and infant mortality.

Incidence, survival and risk factors for the development of veno-occlusive disease in pediatric hematopoietic stem cell transplant recipients

Summary:The incidence, risk factors and mortality of veno-occlusive disease (VOD) were identified for 142 pediatric hematopoietic stem cell (HSC) transplant recipients with hematological malignancies (83), solid tumors (41) and nonmalignant diseases (18). This historical cohort of 142 HSC transplant patients, from January 1993 through June 2000, was assessed by chart review. Risk factors for the development of VOD and mortality were assessed by multiple logistic regression and Kaplan–Meier survival curves respectively. The incidence of VOD was 18.3% (26/142 transplants). Multivariate analysis reconfirmed the known pretransplant risk factors of induction therapy with busulfan and transplantation with matched unrelated donor cells as significant risk factors for the development of VOD. In addition, two new risk factors, positive CMV serology in the recipient and TPN provided in the 30 days prior to transplant, were identified. Mortality in transplant patients at 100 days was greater in the VOD-positive group (10/26 (38.5%)) compared to the VOD-negative group (11/116 (9.5%) (P=0.001)). The risk of death was 4.97 times higher with 95% CIs (2.11, 11.71) for the VOD-positive group. Decreasing the risk factors for VOD may decrease mortality in this patient population.

Neurocognitive, Functional, and Health Outcomes at 5 Years of Age for Children After Complex Cardiac Surgery at 6 Weeks of Age or Younger

OBJECTIVE. This work provides neurocognitive, functional, and health outcomes for 5-year survivors of early infant complex cardiac surgery, including those with chromosomal abnormalities. PATIENTS AND METHODS. Of 85 children (22.4% mortality), 61 received multidisciplinary, individual evaluation and parental questionnaires at 5 years. Full-scale, verbal, and performance IQ scores were compared by using analysis of variance among children who received different surgeries (arterial switch, 20; Norwood for hypoplastic left heart syndrome, 14; simple total anomalous pulmonary venous connection, 6; miscellaneous, 21; and chromosomal abnormalities, 8). Predictions from mental scores at 2 years for IQ scores at 5 years were determined. RESULTS. Children with chromosomal abnormalities had lower full-scale and verbal IQs at 5 years than other survivors, with no differences found among the remaining groups. For children post-Norwood, performance IQ scores remained lower than for children after the arterial-switch operation. Prediction of full-scale IQ (<70) from 2-year mental scores for all 61 children were as follows: sensitivity, 87.5%; specificity, 88.1%; positive predictive value, 53.8%; and negative predictive value, 97.9%. For full-scale IQ of <85, predictions were 90.0%, 87.8%, 78.3%, and 94.7%, respectively. For those 53 without chromosomal abnormalities, full-scale IQ <70, respective predictions were 86.7%, 90.0%, 28.6%, and 97.8%, and for full-scale IQ <85, respective predictions were 85.7%, 89.7%, 75.0%, and 94.6%. Parental report indicated good health in 80% and adequate function in 67% to 88% of the children, although health-utilization numbers suggest that these reports are optimistic. CONCLUSIONS. Five-year full-scale and verbal IQs were similar among groups, excluding those with chromosomal abnormalities. Children with chromosomal abnormalities had the lowest scores. Excluding those with chromosomal abnormalities, the mean mental scores for the children as a group tended to increase from 2 to 5 years of age, with an overall high percentage of correct classifications at 2 years.

Before viability : A geographically based outcome study of infants weighing 500 grams or less at birth

Objective. The primary objective of this study was to determine the likelihood of long-term survival and avoidance of disabilities in a geographically based population of infants born at 20 weeks gestation or more and weighing 500 g or less at birth. Study Design. This was a 12-year historical cohort follow-up study of all infants born in this gestational age and birth weight category in the Province of Alberta, Canada, between 1983 and 1994. Data were collected from certificates of live births or stillbirths, death certificates, hospital records, and longitudinal multidisciplinary follow-up examinations. Results. One thousand one hundred ninety-three infants were of 20 weeks gestation or more, weighed 500 g or less, and were born between 1983 and 1994. Eight hundred eleven (68.0%) were stillborn and 382 (32.0%) were born alive. Among the latter, neonatal intensive care was provided in 113 (29.6%) and withheld in 269 (70.4%). The infants receiving intensive care were of heavier birth weight, later gestational age, higher antenatal risk scores, were more likely to be born in a level III center, to have received antenatal steroids, and to have been delivered by cesarean section. Of the infants receiving intensive care, 95 (84.1%) died and 18 (15.9%) were discharged alive, but 5 of these died after discharge because of respiratory complications. The infants discharged alive had later gestational age, were more likely to be small for gestational age, singletons, treated with antenatal steroids, and to have been delivered by cesarean section. Maternal indications were described in the majority of cesarean sections done for live-born infants. The 13 infants who were long-term survivors were followed at ages 12 and 36 months adjusted age. Four had no serious disabilities, 4 had one disability (cerebral palsy or mental retardation), and 5 had multiple disabilities (cerebral palsy plus mental retardation with blindness in 2 cases and deafness in 1 case). Conclusion. The majority of infants born at gestational age 20 weeks or more weighing <500 g were stillborn. Among live births, neonatal intensive care was withheld in 70% and initiated in 30%. Of the latter, 11% survived to 36 months of age, and of these, 4 infants (31%), most of whom are small for gestational age, female infants, avoided major disabilities but 9 (69%) had one or more major disabilities. Survivors are prone to rehospitalizations early in life, slow growth, feeding problems, and minor visual difficulties; rates of learning-related and behavioral problems at school age are not yet known. Implications. Parents and caregivers faced with the impending delivery of an infant in this gestational age/birth weight category should understand that survival without multiple major disabilities is possible but rare. They should be made aware of local population-based results and not just isolated reports.

The association between neighbourhoods and adverse birth outcomes: a systematic review and meta‐analysis of multi‐level studies

Many studies have examined the role of neighbourhood environment on birth outcomes but, because of differences in study design and modelling techniques, have found conflicting results. Seven databases were searched (1900-2010) for multi-level observational studies related to neighbourhood and pregnancy/birth. We identified 1502 articles of which 28 met all inclusion criteria. Meta-analysis was used to examine the association between neighbourhood income and low birthweight. Most studies showed a significant association between neighbourhood factors and birth outcomes. A significant pooled association was found for the relationship between neighbourhood income and low birthweight [odds ratio = 1.11, 95% confidence interval: 1.02, 1.20] whereby women who lived in low income neighbourhoods had significantly higher odds of having a low birthweight infant. This body of literature was found to consistently document significant associations between neighbourhood factors and birth outcomes. The consistency of findings from observational studies in this area indicates a need for causal studies to determine the mechanisms by which neighbourhoods influence birth outcomes.