|after conception by a urine test.
In the diagnosis of early pregnancy failure, the HCG doubling time is a superior diagnostic parameter compared to the HCG
ratio, with similar sensitivity but better specificity.HCG
levels rise during the first 6 - 10 weeks of pregnancy then
decline slowly during the second and third trimesters.At an hCG level below 1,200 mIU/ml, the hCG usually doubles every 48-72 hours. Between 1,200 and 6,000 mIU/ml serum, the hCG usually takes 72-96 hours to double.
Above 6,000 mIU/ml, the hCG often takes over four days to double.A great way to understand just how rapidly these levels increase is to look at weeks 4 and 5 during pregnancy.
If hCG levels are taken and they not only double, but triple, quadruple or more, this is often a sign that there is more than one baby in the uterus.
Eventually, the amount of hCG will reach a plateau where it will stay for the duration of the pregnancy.