Alpha1-Fetoprotein, cell-free DNA screening, maternal serum screening tests, prenatal screening tests, quad testing (AFP, HCG, estriol, inhibin-A), triple markers (AFP, HCG, estriol).
To assist in the evaluation of fetal health related to chromosomal (e.g., trisomy 18, trisomy 21) or neural tube defects (e.g., spina bifida, anencephaly).
There are no food, fluid, activity, or medication restrictions unless by medical direction or as required by the specific collection procedure.
Each testing laboratory must establish its own reference ranges for quantitative measurements and its own cutoffs for negative and positive findings. Findings are then issued by laboratory report. Serum values for the tests evaluated vary with maternal race, weight, weeks of gestation, diabetic status, and number of fetuses. Variations exist between test methods; therefore, serial testing should be determined using the same test method. The calculated risk of a trisomy is based on the multiples of the median (MoM) of multiple markers, where the MoM is calculated for each marker and applied to an algorithm that includes other information known to influence the incidence of trisomy.
Critical Findings and Potential Interventions
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