Risk Factors of Anencephaly: A Case-Control Study in Dessie Town, North East Ethiopia

Anencephaly is a form of neural tube defect, which develops when the cranial neuropore is unable to close. It is one of the fatal anomalies of the neural tube. Although most of the causes of anencephaly are unknown, multiple risk factors are associated with this defect. Therefore, this study aimed to investigate the incidence and associated risk factors of anencephaly in Dessie town, in the north eastern region of Ethiopia.

An institution-based unmatched case-control study was conducted. Sociodemographic characteristics of pregnant women were collected with a structured questionnaire and clinical data were recorded during an ultrasound examination. Data were entered into Epi Info 7 and analyzed by SPSS version 20. Binary logistic regression was applied to detect the associations between risk factors and the occurrence of anencephaly.

The incidence of anencephaly was 3.3/1000 pregnancies. The multivariate logistic regression model indicated that maternal age between 26 and 30 years and khat chewing during pregnancy were significantly associated with anencephaly (OR 0.13, 95% CI 0.02-0.97, p=0.046; and OR 3.571, 95% CI 1.06-12.06, p=0.04, respectively). Exposure to typhus and typhoid and the use of antihypertensive drugs during early pregnancy were also significantly correlated as anencephaly risk factors. Furthermore, spina bifida simultaneously occurred with anencephaly significantly (p<0.05).

It is suggested that exposure to risk factors such as khat chewing during pregnancy may predispose to the development of anencephaly.