Assays for Fetal Health Screening

New alpha-fetoprotein (AFP) and unconjugated estriol (uE3) assays expand the capabilities of a small, random-access analyzer with an existing assay for the free beta moiety of human chorionic gonadotrophin (hCG), providing full support for the triple test for second trimester risk assessment of Down's syndrome. All three assays are blood tests.

Through the quantitative detection of maternal serum markers, prenatal screening is a safe and noninvasive way to assess the risk of fetal disorders, including chromosomal abnormalities indicating Down's syndrome. In high-risk pregnancies, doctors can provide diagnostic testing to determine specific issues and help patients prepare and adapt to the situation. The screening for abnormalities may be performed in either the first or second trimester of pregnancy, but in either case, it is the custom to measure a combination of markers in order to achieve acceptable levels of sensitivity and specificity.

The two new assays from PerkinElmer (Boston, MA, USA) and the hCG assay are all designed for use on the Delfia Xpress platform of PerkinElmer, which includes software, reagents, and controls. Assays for all the key maternal health screening analytes are also supplied for the company's automatic batch system, AutoDelfia, as well as the Delfia semi-automatic system.

"The random access analyzer complements the high throughput of the AutoDelfia very well and therefore has a potential role for ‘stat' analysis or for small throughput analytes in the large screening laboratory,” noted Sue Standing, consultant scientist, Birmingham Women's Health Care Trust (UK). "Alternatively it could do the whole workload of a small screening center or be used in the prenatal clinic for real-time risk assessment.”