Evaluation of Epidemiology of Anencephaly of 149408 Deliveries

SUMMARY Anencephaly is one of the major congenital neurologic malformations whose incidence had been reported to be of 0.3 to 6 per 1000 births. Due to its importance and undefinite incidence, and the role of certain significant factors that cause the disease in Iran, this study was carried out on 149498 live born and stillborn infants, born in Tehran Medical University centers from 1988 through 1991 using retrospective study, existing data study. The results indicate that the incidence of anencephaly is 0.23 per 1000 total births (23 per 10,000). The incidences varied widely from of least 0.17 to 1.26 per 1000 in different Medical Centers. Thirty-four percent of the infants with anencephaly had been diagnosed after birth, and only 66 percent had been diagnosed in antenatal screening programs. Numbers of pregmancies in mothers with anencephalic infants were 38 % and the condition of giving birth to in relatives of the mothers with anencephalic infants has been twice of that in the control anothers (P<0.05). There has also been no relationship between anencephaly and maternal age.