Low maternal serum levels of pregnancy associated plasma protein A (PAPP-A) in the first trimester in association with abnormal fetal karyotype
Article first published online: 19 AUG 2005
BJOG: An International Journal of Obstetrics & Gynaecology
Volume 100, Issue 4, pages 324–326, April 1993
How to Cite
Brambati, B., Macintosh, M. C. M., Teisner, B., Maguiness, S., Shrimanker, K., Lanzani, A., Bonacchi, I., Tului, L., Chard, T. and Grudzinskas, J. G. (1993), Low maternal serum levels of pregnancy associated plasma protein A (PAPP-A) in the first trimester in association with abnormal fetal karyotype. BJOG: An International Journal of Obstetrics & Gynaecology, 100: 324–326. doi: 10.1111/j.1471-0528.1993.tb12973.x
- Issue published online: 19 AUG 2005
- Article first published online: 19 AUG 2005
- Received 10 March 1992 Accepted 29 September 1992
Objective To assess the relation between maternal serum pregnancy associated plasma protein A (PAPP-A) in the first trimester and the outcome of pregnancy by karyotype.
Design A retrospective study of PAPP-A levels in blood samples collected prior to chorionic villus sampling.
Setting Milan, Italy.
Subjects Five hundred twenty-two women, aged 20 to 47, at 7 to 11 weeks gestation, prior to undergoing chorionic villus sampling. Four hundred forty-five women had a pregnancy with a normal karyotype; in 30 pregnancies the karyotype was abnormal (including 14 cases of Down's syndrome and 7 of trisomy 18).
Main outcome measures Normal or abnormal fetal karyotype. Serum PAPP-A at 6 to 11 weeks gestation measured by radioimmunoassay.
Results The median value of PAPP-A in the abnormal group was 0.27 multiples of the normal median (MoM). This is significantly lower than the median value in the normal group (1.01 MoM) (95% CI for the difference 0.46–0.84 MoM; P<0.00001 Mann-Whitney test).
Conclusions There is an association between low levels of PAPP-A in the first trimester with chromosome anomalies. Screening by measurement of PAPP-A might detect 60% of cases of Down's syndrome in the first trimester with a false positive rate of 5%.