PRENATAL-DIAGNOSIS OF MAJOR MALFORMATIONS - QUALITY-CONTROL OF ROUTINE ULTRASOUND EXAMINATIONS BASED ON A 5-YEAR STUDY OF 20248 NEWBORN FETUSES AND INFANTS

Antenatal ultrasound screening for birth defects is increasingly becom ing a routine procedure of prenatal care. Prenatal detection of malfor mations and subsequent adjustment of obstetric management are essentia l for secondary prevention. It is unknown whether ultrasound screening is effective in ail pregnant women, or should only be performed in hi gh risk populations. From 1990-1994, 20248 livebirths, stillbirths and abortions underwent physical and sonographic examinations and anamnes tic data were collected. To identify the high risk group, case control analyses of births with one of the 23 selected major malformations (c ases) arid births without malformations (controls) were performed with respect to anamnestic risk factors. All women had at east three routi ne ultrasound scans. The selected malformations were diagnosed in 298 children; 95 (30.3 per cent) were diagnosed antenatally. Detection rat es were: CNS (68.6 per cent), gastro-intestinal tract (42.3 per cent), urinary system (24.1 per cent), heart (5.9 per cent). Complications d uring pregnancy were calculated as indicators of congenital anomalies: premature labour (<28 week) OR 4.7 (3.8-5.9), placental insufficiency OR 1.9 (1.1-2.7) and vaginal bleeding OR 1.5 (1.2-1.8), etc. Antenata l routine ultrasound screening is not effective in low risk population s. Anamnestic risk factors during pregnancy may be essential indicator s for identifying high risk populations. We propose screening of the d escribed high risk pregnancies (about 22 per cent of all pregnancies) to be performed by specially trained and highly experienced ultrasonog raphers to increase sensitivity rates and benefit cost effectiveness. (C) 1998 John Wiley & Sons, Ltd.