and Objective: Neural tube defect is one of the most important malformations of the newborns. The aim of this study was to investigate the rates of NTD, anencephaly, spina-bifida cystica, encephalocele and the relation of these abnormalities with sex, ethnicity, mother"s
age and consanguineous marriage in north of Iran (Gorgan).
Materials and methods: A cross - sectional study was done on 26280 birth in Dezyani hospital in Gorgan during 1998 - 2001.
Results: This study has showed that, the NTD rate was 3.08, 2.78 and 3.38 per 1000 in total, males and females, respectively, female to male ratio was 1.31. The rate of spina-bifida, anencephaly and encephalocele were 1.48, 1.48, 0.11 per 1000, respectively. In regard to
different races, the rate was 6.7811000, 4.76/1000 and 2.41/1000 among Turkmans, Systanis and
native Fars, respectively (P<0.05). The rate of NTD in the mothers under 20 years was
2.29/1000, in 20-34 years was 3.37/1000 and over 35 years was 2.54/1000. Interstingly, 29.6%
of parents with affected newborns had consanguineous marriange.
Conclusions: We concluded that there is a higher rate of NTD in this, area, that it might be due
to race - ethnicity variations.