[Maternal serum screening for Down syndrome and neural tube defects].
OBJECTIVE
Evaluation of maternal serum screening for Down's syndrome (DS) and neural tube defects (NTDs).


METHODS
Longitudinal study.


METHODS
Department of Obstetrics and Gynaecology, University Hospital Utrecht, the Netherlands.


METHODS
6362 pregnant women underwent serum screening for DS and (or) NTD between the 15th and 21st weeks of pregnancy between March 1991 and March 1996. Screening was performed using alpha-foetoprotein, unconjugated oestriol, human chorionic gonadotrophin and maternal age. The result of each individual test was a calculated risk for delivering a child with DS and (or) NTD.


RESULTS
Nine out of 12 singleton pregnancies of a foetus with DS were detected. To this purpose, 573 women who, according to the serum screening had an increased risk of a child with the abnormality, were offered amniocentesis, which was performed in 471 of them. Two twin pregnancies with a total of 3 DS affected foetuses were also detected; one twin pregnancy of a DS foetus was screen-negative. The one case of spina bifida was screen-positive. The proportion of women eligible for invasive prenatal diagnosis because of maternal age increased from 9% to 25% in the course of the study. Of 1118 women aged > or = 36 years 913 (82%) declined invasive investigation compared with 40% in the general population.


CONCLUSIONS
The results of the maternal serum screening program in Utrecht were comparable with other studies. Maternal serum screening is accepted as an alternative by women above 36 years, and allows to decrease the need for amniocentesis without a significant loss in detection rate.
van Rijn
M
M
Academisch Ziekenhuis, afd. Obstetrie en Gynaecologie, Utrecht.
Christiaens
G C
GC
van der Schouw
Y T
YT
Hagenaars
A M
AM
de Pater
J M
JM
Visser
G H
GH
D000653:Amniotic Fluid / Q000737:chemistry; D006063:Chorionic Gonadotropin / Q000097:blood; D004200:Diseases in Twins / Q000175:diagnosis; D004314:Down Syndrome / Q000097:blood*; D004964:Estriol / Q000097:blood; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008137:Longitudinal Studies; D008423:Maternal Age; D009436:Neural Tube Defects / Q000097:blood*; D011247:Pregnancy / Q000097:blood*; D011262:Pregnancy Trimester, Second; D018566:Pregnancy, High-Risk; D011296:Prenatal Diagnosis / Q000379:methods; D000509:alpha-Fetoproteins / Q000032:analysis
D006063:Chorionic Gonadotropin; D000509:alpha-Fetoproteins; D004964:Estriol