The incidence of selected congenital malformations during a two-year period in Tehran, Iran.

In this descriptive cross-sectional study carried out from March 2005 to March 2007, 410 congenital malformations were recorded among 61,112 live births in six general hospitals in different districts of Tehran. The overall incidence was 0.6% (0.69% in males and 0.62% in females) and the most affected system was the digestive system (40%), followed by the musculoskeletal system (20.5%), central nervous system (19.5%), genitourinary system (12.2%) and cardiovascular system (3%). It is essential that government organizations educate the population through scheduled preconceptional primary care visits on interventions like diet supplementation and avoidance of teratogenic agents, in order to decrease the rate of congenital malformations.