HCG levels in pregnancy

There is considerable individual variation, but around 50% of normal pregnancies give hCG values within 3 days of the average day. After 60 days cyesis, hCG values plateau and begin to decline. HCG results cannot therefore be used to predict dates for pregnancies of duration likely to be more than 60 days.

The table below shows average hCG (U/L) and days of cyesis (days post LMP)