Fetal anomalies in a controlled one-stage ultrasound screening trial. A report from the Helsinki Ultrasound Trial

Abstract

The aim of the study was to compare whether systematic strictly timed screening of all pregnancies would improve the detection of major fetal anomalies. All pregnant women (95%) from a certain area were randomly allocated for one ultrasound screening examination between the 16th and 20th weeks of gestation. Otherwise the screening (N = 4691) and control groups (N = 4619) received the same antenatal care. Screening included a systematic search for fetal anomalies. In the screening group, 40% of major fetal anomalies were detected in the screening, and 11 abortions were induced because the malformation was either lethal or severely handicapping. In the control group, 77.0% of participants had ultrasound examination any time during pregnancy. By ultrasound 13 (27%) major fetal anomalies were detected, only two of these before the 21st week of gestation. Screening detected most of the anomalies of the central nervous system and genitourinary system and cases with multiple anomalies, but was less satisfactory in detecting the anomalies of the heart and gastrointestinal tract. The perinatal mortality rate was 4.2 per 1000 in the screening group and 8.4 per 1000 in the control group (p = 0.013). The detection of major fetal anomalies in ultrasound screening can reduce perinatal mortality. A systematic search for fetal anomalies should be included in the ultrasound screening of all pregnancies.

Comparison of prenatal ultrasound and postmortem findings in fetuses and infants with central nervous system anomalies

“…Our results confirm an overall good correlation between prenatal ultrasound and postmortem examination of major CNS anomalies 2,6,9,12,38 . No matter how efficient and correct the prenatal diagnoses become, a verification by morphological examination is desirable in order to ensure the necessary quality control 1,2,9,10,[12][13][14]21,27,28 .…”

Comparison of prenatal ultrasound and postmortem findings in fetuses and infants with congenital heart defects

“…It is generally more difficult to detect congenital heart defects by ultrasound than it is to detect CNS anomalies 2,19,20 . The nature of the cardiac anatomy and the wide spectrum of defects make the heart a difficult organ to examine.…”

“…Routine fetal ultrasonographic examination offered in the 18-19th week of pregnancy has in recent years been expanded to include evaluation of fetal anatomy 1,2 . A systematic search for congenital malformations has become an important part of antenatal surveillance.…”

“…Verification of an antenatal diagnosis of cardiac anomaly in a fetus or an infant by autopsy plays an important role in the quality control of the sonographic examination. Several large autopsy studies of aborted fetuses and stillborn infants with congenital anomalies have compared prenatal diagnosis with postmortem examination, with special reference to cardiac defects 1,2,[16][17][18][19][20][21][22] . Previous studies that specifically compared congenital heart defects detected prenatally by ultrasonography with postnatal examination dealt with both clinical findings in live infants and autopsy findings 4,5,[23][24][25][26][27][28] .…”

Evaluation of prenatal ultrasound diagnosis of fetal abdominal wall defects by 19 European registries

“…They therefore represent a good model for the evaluation of the current effectiveness of antenatal diagnosis by ultrasound screening. Although improved perinatal outcome for prenatally diagnosed omphalocele or gastroschisis has not been documented [25][26][27][28] the affected infants can certainly benefit from a planned delivery and surgical treatment. Furthermore, counseling by specialist staff reduces levels of parental anxiety associated with the diagnosis of fetal malformation 29 .…”