Prevalence and distribution of congenital abnormalities in Turkey: Differences between the prenatal and postnatal periods

The aim of this study was to determine the distribution of cases associated with congenital abnormalities during the following three periods: pregnancy, birth, and the neonatal period. This was a retrospective study of cases between 2002 and 2006. All abnormal pregnancies, elective terminations of pregnancies, stillbirths, and births with congenital abnormalities managed in the Neonatology Unit were classified based on the above distribution scheme. During the 5-year study period, 1906 cases with congenital abnormalities were recruited, as follows: 640 prenatally detected and terminated cases, with most abnormalities related to the central nervous system, chromosomes, and urogenital system (56.7%, 12.7%, and 8.9%, respectively); 712 neonates with congenital abnormalities (congenital heart disease [49.2%], central nervous system abnormalities [14.7%], and urogenital system abnormalities [12.9%]); and hospital stillbirths, of which 34.2% had malformations (220 prenatal cases [34.4%] had multiple abnormalities, whereas 188 liveborn cases [26.4%] had multiple abnormalities). The congenital abnormalities rate between 2002 and 2006 was 2.07%. Systematic screening for fetal anomalies is the primary means for identification of affected pregnancies.