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Background: In 1998, fortification of a large variety of cereal products with folic acid became mandatory in Canada. A multicentric study was carried out to assess the impact of this policy on the frequency of NTDs. The present analysis focused on spina bifida., Methods: The study population included approximately 2 million livebirths, stillbirths, and terminations of pregnancies because of fetal anomalies among women residing in seven Canadian provinces, from 1993 to 2002. Spina bifida cases were divided according to the upper limit of the defect: upper (cranial, cervical, or thoracic) and lower (lumbar or sacral) defects. Based on published results of red blood cell folate tests, the study period was divided into prefortification, partial fortification, and full fortification periods., Results: A total of 1,286 spina bifida cases were identified: 51% livebirths, 3% stillbirths, and 46% terminations. Prevalence decreased from 0.86/1,000 in the prefortification to 0.40 in the full fortification period, while the proportion of upper defects decreased from 32% to 13%. Following fortification, regional variations in the prevalence and distribution of sites almost disappeared., Conclusions: Results confirmed the etiologic heterogeneity of spina bifida and the more pronounced effect of folic acid in decreasing the risk of the more severe clinical presentations., ((c) 2008 Wiley-Liss, Inc.)

Background: In 1998, folic acid fortification of a large variety of cereal products became mandatory in Canada, a country where the prevalence of neural-tube defects was historically higher in the eastern provinces than in the western provinces. We assessed changes in the prevalence of neural-tube defects in Canada before and after food fortification with folic acid was implemented., Methods: The study population included live births, stillbirths, and terminations of pregnancies because of fetal anomalies among women residing in seven Canadian provinces from 1993 to 2002. On the basis of published results of testing of red-cell folate levels, the study period was divided into prefortification, partial-fortification, and full-fortification periods. We evaluated the relationship between baseline rates of neural-tube defects in each province and the magnitude of the decrease after fortification was implemented., Results: A total of 2446 subjects with neural-tube defects were recorded among 1.9 million births. The prevalence of neural-tube defects decreased from 1.58 per 1000 births before fortification to 0.86 per 1000 births during the full-fortification period, a 46% reduction (95% confidence interval, 40 to 51). The magnitude of the decrease was proportional to the prefortification baseline rate in each province, and geographical differences almost disappeared after fortification began. The observed reduction in rate was greater for spina bifida (a decrease of 53%) than for anencephaly and encephalocele (decreases of 38% and 31%, respectively)., Conclusions: Food fortification with folic acid was associated with a significant reduction in the rate of neural-tube defects in Canada. The decrease was greatest in areas in which the baseline rate was high., (Copyright 2007 Massachusetts Medical Society.)

Objective: To determine the current survival rate of singleton living newborns born at gestational age of 24 and 25 weeks, using obstetric factors available to the physician before birth., Design: Retrospective study of all live births in 13 of 17 Canadian tertiary centres. Population All singleton live births without congenital abnormalities., Methods: During the years 1991-1996, data were abstracted from clinical databases and charts of 860 live births, in 13 of the 17 tertiary centres in Canada, all with major neonatal intensive care units. Newborn survival was defined as alive at discharge from neonatal intensive care unit. Abstracted elements included gestational age, maternal antenatal corticosteroid treatment, birthweight, gender, fetal presentation and mode of delivery., Results: Average survival rates increased from 56.1% at 24 weeks (n = 406) to 68.0% at 25 weeks (n = 454). Survival rates ranged from 53.1% at day 168 to 81.6% at day 181 (r = 0.802, P < 0.05). Steroid administration improved the survival rates at 24 and 25 weeks compared with that of unexposed fetuses, respectively (58.9% vs 41.8%; OR 1.70; 95% CI 1.03-2.08 and 74.2% vs 56.8%; OR 2.19; 95% CI 1.41-3.38). Caesarean delivery for breech presentation improved survival compared with vaginal delivery, both at 24 and 25 weeks (56.1% vs 36.0%; OR 2.19; 95% CI 1.10-4.34, and 68.7% vs 55.2% OR 1.78; 95% CI 0.093-3.43). Female neonates displayed better survival rates (59.6% vs 52.1% OR 1.36; 95% CI 0.92-2.01, and 72.6% vs 63.1% OR 1.51; 95% CI 1.02-2.25) at 24 and 25 weeks, respectively. Explanatory regression model confirmed these factors as prognostic variables associated with survival., Conclusions: This extensive collaborative study confirms that several prognostic factors, known before birth, including gestational age in days, steroid treatment, mode of presentation and fetal sex may help obstetricians, neonatologists and parents in their decision-making process at 24 and 25 weeks of pregnancy.