Detection of congenital malformations in healthy pregnant ladies undergoing routine scan

Aim: to detect the congenital malformations in healthy pregnant ladies on routine ultrasonography. material and methods: this purposive sampling study was carried out in dhq teaching hospital,dera ghazi khan from october 2011 to october 2012. a total of 480 healthy pregnant ladies attending outpatients department at 18-20 weeks of gestation were screened for congenital malformations with the help of usg. results: the incidence of major congenital malformations was found to be 7.1%. the central nervous system was the commonest involved (61.6%),followed by genitourinary tract (11.7%) and gestational 9%. a significant number of fetuses showed anencephaly 4.5% and hydrocephalus 2%. false positive rate was 2.9% while one case of meningiocele,spina bifida occulta and bilateral renal agneesis were missed i.e. false negative rate was 5.8%. termination of pregnancy was done in 79% of cases with severe malformations and 21% underwent spontaneous miscarriage or death in utero. conclusion: it is concluded that mid-trimester ultrasound examination is an effective and useful method for screening anatomical congenital malformations.