End‐result of routine ultrasound screening for congenital anomalies: The Belgian Multicentric Study 1984–92

Abstract

Five ultrasound laboratories from Obstetrics and Gynecology departments of Belgian university hospitals or affiliated institutions conducted a prospective study from 1984 to 1992 in which the results of prenatal ultrasound examinations were compared to examination reports of the neonates. The results of the period 1984-89 (PI) have been published previously, and those of the period 1990-92 (PII) are presented here. Some very minor congenital anomalies, as listed and defined in the EUROCAT Register, were excluded. Of 26,147 pregnant women at normal risk for congenital anomalies, 25,046 had at least one ultrasound scan (96%). A total of 616 fetuses were structurally abnormal (prevalence 2.42%), and 685 abnormalities were recorded. The sensitivity of the ultrasound test was 40.4% in PI and 51.1% in PII for abnormal fetuses (p < 0.05), and 45% (PI) and 64% (PII) for abnormalities (p < 0.01). The specificity was 99.9% and the positive and negative predictive values were 94.2% and 98.6%, respectively; these values did not differ significantly between the two periods. The sensitivity for the detection of anomalies before 23 weeks increased from 21% in PI to 41% in PII, indicating an improvement in the early detection of fetal abnormalities.

Ancillary benefits of prenatal maternal serum screening achieved in the California program

“…The ultrasound must be performed by a physician who is board certified in radiology or obstetrics/gynecology and has completed a fellowship with subspecialty training related to fetal medicine. All ultrasound practices must be accredited The reported prevalence in the general population of fetuses with anomalies at second trimester varies widely from 1.2 to 3.1% (Chitty et al, 1991;Levi et al, 1991;Luck et al, 1992;Shirley et al, 1992;Crane et al, 1994;Levi et al, 1995;Skupski et al, 1996;Boyd et al, 1998;Lee et al, 1998;Magriples et al, 1998;VanDorsten et al, 1998;Bricker et al, 2000). The reported sensitivity for the detection of fetal abnormalities by ultrasound in the second trimester also varies widely from 8.7 to 85.0% (Chitty et al, 1991;Levi et al, 1991;Luck et al, 1992;Shirley et al, 1992;Crane et al, 1994;Levi et al, 1995;Skupski et al, 1996;Boyd et al, 1998;Lee et al, 1998;Magriples et al, 1998;VanDorsten et al, 1998;Bricker et al, 2000).…”

Ultrasound and Diagnosis of Fetal Anomalies

“…The passive detection system report 2 to 3% of newborns, 1,2 meanwhile the active detection system, in which newborns are systematically examined by trained obstetricians, report of the incidence of congenital defects in 7.3% of all newborns. 3,4 Etiology About 20% of anomalies in live-born infants are based on a defective gene, 10% are due to chromosomal abnormalities and 10% are mainly due to exogenous injury to the conceptus.…”

Prenatal diagnosis

“…Anomalies with the highest detection rates are those of the genitourinary tract (85%), spine and central nervous system (85%), and the gastrointestinal tract (74%). The lowest detection rates are for cardiac defects (32%) and most muscular and skeletal anomalies (30%) 3,8,9 .…”