hCG is the primary analyte used for pregnancy confirmation and monitoring due to its rapid rise in both blood and urine soon after conception (1). The detection of hCG within 3 - 4 weeks of the last menstrual period is the most reliable indicator for the confirmation of pregnancy. During a normal pregnancy, levels of hCG in the blood vary but are approximately 25 - 50 mIU/mL in the week after conception and rise exponentially doubling every 1.5 - 3 days during the first six weeks (2,3). hCG levels continue to rise through the end of the first trimester, followed by a slow decline as the pregnancy reaches full-term (~ 40 weeks).
Each laboratory should establish its own expected values that represents the population that is to be evaluated at their facility. As a guide, the following ranges were determined. The IB10 sphingotest® beta-hCG Test was used to determine the concentration upper reference limit of hCG in human plasma samples collected from apparently healthy, non-pregnant individuals. The 95th percentile upper reference limit as determined with the samples is 5.42 mIU/mL hCG.
|Reference Group||N||Median (mIU/mL)||95th percentile (mIU/mL)|
|Female age <50||150||0.4||4.2|
|Female age >50||98||3.3||7.9|
Representative hCG ranges during normal pregnancy based on Last Menstrual Period (LMP) are summarized below. Other clinical reference citations may show different values.
|After LMP (weeks)||hCG Range (mIU/mL)2|
|4||5 - 100|
|5||200 - 3,000|
|6||10,000 - 80,000|
|7-14||90,000 - 500,000|
|15-26||5,000 - 8,000|
|27-40||3,000 - 15,000|
Whole Blood vs. Plasma Comparison
All our assays correlate with r=0.9. For more detailed information please read the IFUs or connect with our sales representatives.
(1) Canfield RE et al. Development of an assay for a biomarker of pregnancy and early fetal loss. Environ Health Perspect. 1987 Oct;74:57-66.
(2) Vaitukaitis JL et al. Gonadotropins and their subunits: basic and clinical studies. Recent Prog Horm Res. 1976;32:289-331.
(3) Wu A. Tietz clinical guide to laboratory tests. 2006. 4th Ed. Philadelphia - Saunders-Elsevier - pp. 252-259