Clinical first-trimester routine screening for Down syndrome in singleton pregnancies in northern Finland.
OBJECTIVE
The purpose of this study was to compare the efficacy of both separate and combined maternal serum testing and fetal nuchal translucency measurement in the first trimester screening for Down syndrome in northern Finland.


METHODS
The following screening tests were evaluated: measurement of nuchal translucency (NT) alone; serum screening (pregnancy-associated plasma protein A [PAPP-A] and free beta subunit of human chorionic gonadotropin [beta-hCG]) alone; and combined screening (NT plus PAPP-A and free beta-hCG).


RESULTS
The participants comprised 7534 pregnant women during the 10+0-12+6 weeks of pregnancy. All 7534 women participated in serum screening, and 4765 women participated in combined screening. In the serum screening-alone group, there were 30 cases of trisomy 21, of which 23 (76%) were detected. In the combined-screening group, there were 24 cases of trisomy 21 and 21 (87.5%) were detected. In the combined-screening group NT alone detected 15 cases of Down syndrome (62%).


CONCLUSIONS
Combined screening is the method of choice for Down syndrome screening.
Valinen
Yrtti
Y
Department of Obstetrics and Gynecology, Department of Oulu University Hospital, Finland.
Rapakko
Katrin
K
Kokkonen
Hannaleena
H
Laitinen
Paivi
P
Tekay
Aydin
A
Ahola
Tarja
T
Ryynanen
Markku
M
D000328:Adult; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000097:blood*; D004314:Down Syndrome / Q000175:diagnosis*; D005260:Female; D005387:Finland; D006801:Humans; D048208:Nuchal Translucency Measurement; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011266:Pregnancy-Associated Plasma Protein-A / Q000032:analysis*; D011296:Prenatal Diagnosis
D018997:Chorionic Gonadotropin, beta Subunit, Human; D011266:Pregnancy-Associated Plasma Protein-A