First trimester screening for trisomy 21; Do the parameters used detect more pathologies than just Down syndrome?
OBJECTIVE
To assess the value of first trimester maternal serum free beta human chorionic gonadotropin (beta hCG), pregnancy-associated plasma protein (PAPP-A) concentrations and nuchal translucency (NT) as predictors of pregnancy complications.


METHODS
A retrospective collaborative study of beta hCG, PAPP-A and NT between 10 and 14 weeks of pregnancy in patients in whom pregnancy was followed to term. Nuchal translucency, maternal serum PAPP-A and free beta hCG concentrations were measured in 1779 women with singleton pregnancies and without aneuploidies. Individual values were expressed as multiple of medians (MoM). Normal and abnormal pregnancies were compared for these parameters.


RESULTS
Irrespective of the presence or absence of pregnancy-associated pathologies; there was no change in the median MoM for NT. The median MoM for free beta hCG was significantly increased in women with threatened abortions whereas the median MoMs for PAPP-A in women with spontaneous abortions or with pre-term deliveries were decreased significantly compared to normal pregnancies. These parameters have however no clinical usefulness as determined by receiver operator characteristics curves.


CONCLUSIONS
Since PAPP-A is a protease that specifically degrades insulin-like growth factor binding proteins we would conclude that the control of the insulin-like growth factor system in the first trimester of pregnancy might play a key role in determining subsequent pregnancy outcome.
Kabili
Genc
G
Department of Obstetrics and Gynaecology, University of Geneva, Switzerland.
Stricker
Reto
R
Stricker
René
R
Extermann
Philippe
P
Bischof
Paul
P
D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000097:blood; D004314:Down Syndrome / Q000097:blood / Q000175:diagnosis* / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D009333:Neck / Q000000981:diagnostic imaging / Q000196:embryology; D011237:Predictive Value of Tests; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood / Q000175:diagnosis / Q000000981:diagnostic imaging; D011261:Pregnancy Trimester, First; D011266:Pregnancy-Associated Plasma Protein-A / Q000378:metabolism; D011296:Prenatal Diagnosis; D012372:ROC Curve; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014463:Ultrasonography
D018997:Chorionic Gonadotropin, beta Subunit, Human; D011266:Pregnancy-Associated Plasma Protein-A