Increase >53% in 48hrs (until 10,000 mIU/ml)
Depends on the initial value:
<1500 --> 50% increase
1500-3000 --> 40% increase
> 3000 --> 30% increase
<1500 --> 50% increase
1500-3000 --> 40% increase
> 3000 --> 30% increase
Increases or decreases slowly ("plateau")^
Decreases >20% in 48 hrs
^Initial level CANNOT be used to rule-out ectopic
Beta-HCG
SCVMC:EXC
MHH-TMC
Oxytocin
ACTH 
SCVMC:ED
Tdap
OVMC:ED