Orofacial clefts and risk factors in Tehran, Iran: A case control study

Background Non-syndromic cleft lip with or without cleft palate (CL/P) or cleft palate only (CPO) are orofacial clefts with multifactorial etiology. These include environmental factors and heterogeneous genetic background. Therefore, studies on different and homogenous populations can be useful in detecting related factors. The aim of the present study was to evaluate the risk factors in patients with non-syndromic cleft in Tehran, Iran. Methods Data from 300 patients and 300 controls were collected between 2005 and 2010. Binary logistic regression analyses were used to calculate relative risk by odds ratio (OR) and %95 confidence interval. Results Low maternal age (OR=1.06, 95% CI, 1.011-1.113), low socioeconomic status (OR=0.23, 95% CI, 0.007-0.074), maternal systemic disease (OR=0.364; 95% CI, 0.152-0.873) and passive smoking (OR=0.613, 95% CI, 0.430-0.874) increased the risk for CL/P and CPO. There was a significant difference in iron and folic acid use during pregnancy when the case and control groups were compared. Conclusion In assessing for orofacial cleft risk, we should consider lack of folic acid supplementation use, maternal age and systemic diseases and passive smoking as risk factors.