Pattern of congenital malformations in consanguineous versus nonconsanguineous marriages in Kashan, Islamic Republic of Iran.

This study determined the types, patterns and prevalence of congenital malformation among the offspring of consanguineous and nonconsanguineous parents. In this prospective study of 3529 neonates delivered alive during a 1-year period, 109 had congenital malformations (3.09/1000 live births). The rate of congenital malformation was 2.0% among neonates from nonconsanguineous marriages and 7.0% from consanguineous marriages. The most common malformations were genitourinary (32.1%), musculoskeletal (22.0%) and cardiovascular (14.7%). Of the total malformed infants, 8.3% died within the neonatal period. Male infants were at greater risk for birth malformations. A history of congenital malformation was more common in siblings of consanguineous than nonconsanguineous marriages.