Objective: Neural tube defects including anencephaly, encephalocele, and spina bifida are major congenital malformations with multifactorial etiology, and with a great variation in their prevalence in different populations. The study on the Prevalence of the malformations may be helpful in planning strategies for their prevention. The aim of this epidemiologic descriptive study was to determine the prevalence of neural tube defects and to describe their birth characteristics in Motahhari hospital, Urmia, West Azerbaijan.Materials and Methods: A cross-section observational study was carried on the hospital-based charts of consecutive 13997 live-births and 124 stillbirths during the period January 2001 through June 2005. The defects categorized based on the domains of anencephaly, spina bifida, and encephalocele according to standard definitions.Results: During this period, 117 cases were detected with neural tube defects, giving an overall prevalence of 8.29/1000. Of 117 cases, 81 (69.23%) cases were seen among stillbirths and 36 (30.77%) cases among live-births, that is, the prevalence of neural tube defects for stillbirths and live-births were 653.2/1000 and 2.57/1000 respectively. The yearly prevalence varies between 6.99/1000 and 9.82/1000 over the 4.5-year period. The major lesion was anencephaly with prevalence of 5.52/1000 (66.67% of all neural tube defects). Approximately, two-thirds (66.09%) of cases were found in females. Weights of 73.36% of anencephalic cases were less than 1000 grams.Conclusion: In this study, the prevalence of neural tube defects is among the highest reported rates. There was a significance difference in the prevalence of anencephaly, as the most prevalent NTD, between live-births and stillbirths. These findings may necessitate an intensive approach to periconceptional folic acid supplementation as a possible strategy to reduce the prevalence of these defects.

Background: Neural tube defects (NTDs) including spina bifida and anencephaly are the second most common birth defects with 2.8 per 1000 births in northern Iran.Objectives: This study was conducted to determine the risk factors of neural tube defects in Gorgan, north of Iran.Patients and Methods: This hospital-based, case-control study was carried out on all NTD-affected pregnancies (n=59) during February 2007 - August 2010, and 160 healthy pregnancies were selected via convenient sampling method in three hospitals in Gorgan, north of Iran. Risk factors including maternal body mass index (BMI), season of birth, gender of the newborn, mother’s age, ethnicity, consanguineous marriage, folic acid consumption, nutrition, habitat, and education, were assessed through interviews with mothers. Univariate and multivariate logistic regression analyses were used to estimate the risks by odds ratios (ORs) and 95% confidence intervals.Results: The multivariate analysis showed that maternal BMI (normal/underweight OR: 0.23, overweight/underweight OR: 0.15, obese/underweight OR: 0.13) and maternal ethnicity (Fars/Sistani OR: 3.49) and maternal nutrition (good/poor OR: 0.46) were significantly correlated with NTDs in the newborns.Conclusions: This study showed that maternal ethnicity, insufficient nutrition, and BMI, were the main risk factors of NTDs in northern Iran.

Statistical data from 1966 till 1995 showed that Neural tube defects, in the American continent, Venezuela had the highest prevalence of 38.9 and some Latin American countries showed the low of 7.7. In Europe, Norway had the highest prevalence of 68, and Denmark the lowest, 5.8. In Asia, India had the highest of 181.8 and Japan the lowest of 10. In Africa, Nigeria had the highest of 70 and Negroes of South Africa had the lowest of 9.9. In Australia the figure was 20.05. According to the statistics available of the years 1967 till 1996, anencephaly in China had the highest prevalence of 87. In the American continent, state of Michigan in the USA had the highest of 10.5 and Jamaica, in Central America, had the lowest of 2.6. In Europe, Turkey with 16.4 and Italy with 2.73; in Asia, China with 87 and Iran with 0.8 had the highest and the lowest prevalence, respectively. In Africa, Nigeria with 3.5, and in Oceania, Newzeland with 7.8 in 10000, were reported. Data available on spina bifida, from the years 1968 till 1991 showed the highest prevalence in China with 36, and the lowest in the Alps Mountains with 0.55 in 10000 individuals. In the American continent, state of Arkansas with 7.8 and California with 3.87; in Europe, England with 23.1 and Rhein-Alp with 0.55 in 10000 had the highest and the lowest prevalence. Finally, in China this rate was 36, in Australia 10, in Newzeland 9.4, and in Nigeria 7/10000. In a study carried out in Tehran, from 1969 till 1978 by the authors, out of 13037 births, (17.6 in 10000) newborns had neural tube defects, with anencephaly 0.8 and spina bifida 3.8/10000. In a new study on 8585 deliveries (1991-1997) in Hamadan (a North West province of Iran), Prevalence of total NTDs was 50.1/10000, anencephaly 15.6 and spin bifida 6.98.