Na. Bersinger et al., FIRST-TRIMESTER MATERNAL SERUM PREGNANCY-ASSOCIATED PLASMA-PROTEIN-A AND PREGNANCY-SPECIFIC BETA-1-GLYCOPROTEIN IN FETAL TRISOMIES, British journal of obstetrics and gynaecology, 101(11), 1994, pp. 970-974
Objective To examine the potential value of maternal serum levels of p
regnancy-associated plasma protein A (PAPP-A) and pregnancy-specific b
eta 1-glycoprotein (SP1) in the detection of fetal trisomy. Design Cro
ss-sectional study. Setting The Harris Birthright Research Centre For
Fetal Medicine, King's College Hospital Medical School, London, UK and
Division of Maternal-Fetal Medicine, Jefferson Medical College, Phila
delphia, USA. Subjects and methods Maternal serum PAPP-A and SP1 conce
ntrations were measured at 10 to 13 weeks gestation in samples from 42
pregnancies with fetal trisomy (trisomy 21, n = 29; trisomy 18, n = 9
; trisomy 13, n = 4) and in samples from 210 matched controls. Results
In controls, both maternal serum PAPP-A and SP1 increased significant
ly with gestation and in trisomic fetuses levels of both hormones were
reduced. However, discriminant analysis demonstrated that SP1 did not
contribute significantly in the distinction between trisomic and cont
rol pregnancies. Although levels of PAPP-A were reduced throughout the
gestational range examined (10 to 13 weeks), especially in cases with
fetal trisomy 21, the deviation was more pronounced at 10 to 11 weeks
than at 12 to 13 weeks gestation. In 45 % of pregnancies with fetal t
risomy 21 and 70 % of pregnancies with trisomies 18 or 13 maternal ser
um PAPP-A levels at 10 to 11 weeks gestation were below the 5th centil
e of the normal range. Conclusion Maternal serum PAPP-A concentration
in the first trimester of pregnancy may prove to be useful in the pred
iction of risk for fetal trisomies.