REFERENCE CENTILE CHARTS OF PAPP-AAND FREE β-HCG IN INDIAN PREGNANT WOMEN.

Abstract

The combined rst-trimester screening (CFTS) for fetal aneuploidy involves a combination of maternal age, fetal nuchal translucency (NT), maternal serum pregnancy-associated plasma protein-A(PAPP-A) and free β-human chorionic gonadotropin (β-hCG) from 11+0 to 13+6 weeks of gestation [1]. International prescriptive standards for early fetal linear size and ultrasound dating of pregnancy in the rst trimester are available and used throughout the world. Ethnicity has an effect on the biochemical parameters of rst trimester screening. As there is a lack of reference chart for the women of Indian ethnicity, we aimed to nd out the level of PAPP-Aand free β-hCG for fetal crown rump length (CRL) of 40-84 mm in the rst trimester of pregnancy and construct the centile charts for both the parameters. Asignicant but weak correlation between the individual models of PAPP-A and β-hCG and CRL (P<0.001). In conclusion, the normal range of PAPP-A and free β-hCG depending on the gestation (CRL) was derived in this cohort study. This would act as a reference for our population and would be helpful in calculating the risk of an adverse maternal and fetal outcome.