[1][2][3] MoM was originally used as a method to normalize data from participating laboratories of Alpha-fetoprotein (AFP) so that individual test results could be compared.
35 years later, it is the established standard for reporting maternal serum screening results.
[4] An MoM for a test result for a patient can be determined by the following: As an example, Alpha-fetoprotein (AFP) testing is used to screen for a neural tube defect (NTD) during the second trimester of pregnancy.
If the median AFP result at 16 weeks of gestation is 30 ng/mL and a pregnant woman's AFP result at that same gestational age is 60 ng/mL, then her MoM is equal to 60/30 = 2.0.
In other words, her AFP result is 2 times higher than median.