Reference range for normal hCG levels in Down syndrome screening
Sep 02, 2022
Source: Cainiu Health
Dr. Chen Zhe
Introduction
The reference range for the multiple of the median (MoM) of hCG in the Down syndrome screening test is 0–2.5; values above this threshold warrant special attention. Currently, the Down syndrome screening test measures the concentrations of AFP and β-hCG in maternal blood and, combined with the mother’s age, uses computerized algorithms to precisely calculate the individual risk and probability of carrying a fetus with Down syndrome.
Down syndrome screening is a test designed to assess the likelihood that a fetus has Down syndrome. Its results are not definitive diagnoses but rather risk estimates—i.e., the probability of the fetus having Down syndrome. So, what is the normal reference range for hCG in Down syndrome screening?
Normal Reference Range for hCG in Down Syndrome Screening
The median multiple (MoM) reference range for hCG in Down syndrome screening is 0–2.5. Values above this threshold warrant special attention. Elevated levels may result from physiological factors—such as inaccurate recall of the last menstrual period or multiple gestation—which are generally not cause for concern. However, they may also indicate pathological conditions—including molar pregnancy or pregnancy-induced hypertension—that pose serious risks to fetal health and development.
Currently, Down syndrome screening involves measuring maternal serum concentrations of alpha-fetoprotein (AFP) and beta-human chorionic gonadotropin (β-hCG), then integrating these values with maternal age using computerized algorithms to calculate each woman’s individual risk of carrying a fetus with Down syndrome. Prenatal Down syndrome screening aims to analyze maternal blood for serum levels of alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), and unconjugated estriol (uE3), combined with clinical information—including maternal age, weight, smoking status, and preexisting medical conditions—to estimate the risk of fetal congenital abnormalities.
In fact, a high-risk screening result does not necessarily mean the fetus has Down syndrome, nor does a low-risk result guarantee the absence of Down syndrome. Further diagnostic testing is required. We hope this answer has been helpful. Wishing you a happy life and good health!
