Beta HCG, Quantitative
1 SST/1.0 mL serum. After 30 minutes of clotting, promptly centrifuge and refrigerate serum.
Refrigerated: 3 days; Frozen: 1 year
In pregnancy, the levels of BHCG increase exponentially for about 8 to 10 weeks after the last menstrual cycle. Later in pregnancy, about 12 weeks after conception, the concentration of BHCG begins to fall as the placenta begins to produce steroid hormones. Other sources of elevated BHCG values are ectopic pregnancy, threatened abortion, microabortion, and recent termination of pregnancy.