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Abstract Background Current fetal-infant growth references have an obvious growth disjuncture around 40 week gestation overlapping where the fetal and infant growth references are combined. Graphical smoothening of the disjuncture to connect the matching percentile curves has never been validated. This study was designed to compare weight gain patterns of contemporary preterm infants with a fetal-infant growth reference (derived from a meta-analysis) to validate the previous smoothening assumptions and inform the revision of the Fenton chart. Methods Growth and descriptive data of preterm infants (23 to 31 weeks) from birth through 10 weeks post term age were collected in three cities in Canada and the USA between 2001 and 2010 (n = 977). Preterm infants were grouped by gestational age into 23–25, 26–28, and 29–31 weeks. Comparisons were made between the weight data of the preterm cohort and the fetal-infant growth reference. Results Median weight gain curves of the three preterm gestational age groups were almost identical and remained between the 3rd and the 50th percentiles of the fetal-infant-growth-reference from birth through 10 weeks post term. The growth velocity of the preterm infants decreased in a pattern similar to the decreased velocity of the fetus and term infant estimates, from a high of 17–18 g/kg/day between 31–34 weeks to rates of 4–5 g/kg/day by 50 weeks in each gestational age group. The greatest discrepancy in weight gain velocity between the preterm infants and the fetal estimate was between 37 and 40 weeks; preterm infants grew more rapidly than the fetus. The infants in this study regained their birthweight earlier compared to those in the 1999 National Institute of Child Health and Human Development report. Conclusion The weight gain velocity of preterm infants through the period of growth data disjuncture between 37 and 50 weeks gestation is consistent with and thus validates the smoothening assumptions made between preterm and post-term growth references.

This study describes the vocal development of infants born with very low birth weights (VLBW). Samples of vocalizations were recorded from three groups of infants when they were 8, 12 and 18 months of age: preterm VLBW infants with bronchopulmonary dysplasia (BPD), preterm VLBW infants without BPD, and healthy full-term infants. Infants with BPD produced significantly smaller canonical syllable ratios than the full-term infants throughout the period of study. Premature VLBW infants who did not suffer from BPD produced relatively little canonical babble at 8 months of age, but were performing within the range of the full-term infants at 18 months of age. At 18 months of age, the infants with BPD were reported to have significantly smaller expressive vocabulary sizes than the healthier preterm and full-term infants.

BACKGROUND: Congenital heart defects may be environmentally related, but the association with elevated ambient temperature has received little attention. OBJECTIVES: We studied the relationship between outdoor heat during the first trimester of pregnancy and risk of congenital heart defects. METHODS: We carried out a retrospective cohort study of 704,209 fetuses between 2 and 8 weeks postconception from April to September in Quebec, Canada, 1988-2012. We calculated the prevalence of congenital heart defects at birth according to the number of days women were exposed to maximum temperature ≥ 30°C. In log-binomial regression models, we estimated prevalence ratios (PR) and 95% confidence intervals (CI) for the relationship of temperature with seven critical and eight noncritical heart defects, adjusted for pregnancy characteristics. RESULTS: Prevalence of congenital heart defects was 979.5 per 100,000 for 10 days or more of temperature ≥ 30°C compared with 878.9 per 100,000 for 0 days of exposure. Temperature was more precisely associated with noncritical than critical defects, which had lower prevalence. Fetuses exposed to 15 days of temperature ≥ 30°C between 2 and 8 weeks post-conception had 1.06 times the risk of critical defects (95% CI: 0.67, 1.67) and 1.12 times the risk of noncritical defects (95% CI: 0.98, 1.29) relative to 0 days. Associations were higher for atrial septal defects (PR 1.37, 95% CI: 1.10, 1.70) than for other noncritical defects. For atrial septal defects, associations with elevated temperatures began the 3rd week postconception. CONCLUSIONS: Extreme heat exposure during the first trimester may be associated with noncritical heart defects, especially of the atrial septum. http://dx.doi.org/10.1289/EHP171., Introduction Congenital heart defects are a leading congenital anomaly worldwide, occurring in every 8 live births per 1,000 (van der Linde et al. 2011). Most congenital heart defects are noncritical, [...]

A drop in infant mortality in Canada between 1995 and 1997 was most likely a result of prenatal diagnosis of birth defects that convinced the mother to have an abortion. The rate of infant death from severe birth defects dropped 21% between 1995 and 1997., Context: Prenatal diagnosis and termination of affected pregnancies can prevent infant deaths due to congenital anomalies, but an effect at the population level has not been shown. Objective: To examine the impact of recent changes in congenital anomaly--related fetal and infant deaths on overall population-based infant mortality. Design, Setting, and Subjects: Birth cohort-based study of all live births, stillbirths, and infant deaths in Canada (excluding Ontario) for 1991-1998. Main Outcome Measures: Cause-specific infant mortality rates and gestational age--specific fetal death rates. Results: The birth cohort-based infant mortality rate fluctuated between 6.4 and 6.1 per 1000 live births between 1991 and 1995, then dropped to 5.4 per 1000 in 1996 and 5.5 per 1000 in 1997. The rate of infant death from congenital anomalies was stable between 1991 and 1995 but declined by 21% (95% confidence interval, 19%-32%) from 1.86 per 1000 in 1995 to 1.47 per 1000 in 1996 and 1997. Fetal deaths due to pregnancy termination at 20 to 23 weeks' gestation increased dramatically in 1994, while fetal deaths due to congenital anomalies at 20 to 21 weeks increased in 1995 and subsequently. Provinces/territories with high rates of fetal death due to pregnancy termination/congenital anomalies at 20 to 23 weeks had fewer infant deaths due to congenital anomalies. Conclusion A large decrease in infant deaths due to congenital anomalies was associated with the most recent decline in infant mortality in Canada, suggesting that increases in prenatal diagnosis and pregnancy termination for congenital anomalies are related to decreases in overall infant mortality at the population level.

Survival without disability is extremely rare for infants born weighing 500 grams or less. Researchers evaluated the outcomes of 1,193 infants in this extremely low birth weight category born from 1983 to 1994 in Alberta, Canada. Almost 70% were stillborn, and only 30% of the live-born infants received neonatal intensive care, based on size, gestational age, and risk factors. Eighty-four percent of these treated infants died in the hospital. Survivors had cerebral palsy, retardation, blindness and other disabilities. Only four infants survived without any serious medical conditions., 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 [is less than] 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. Pediatrics 1998;101:438-445; viability, extremely low birth weight, outcome, disabilities, ethics., The birth of extremely low birth weight infants poses serious dilemmas for families and health care providers because mortality, morbidity, and human and economic costs are high, and the likelihood [...]