The hCG levels grow exponentially after conception and implantation. hCG levels typically peak around weeks 8-11 of pregnancy and are generally higher in the first trimester compared to the second trimester.
The following is a list of serum hCG levels:
LMP is the last menstrual period dated from the first day of the last menstrual period 
If a pregnant woman has serum hCG levels that are higher than expected, they may be experiencing a multiple pregnancy or an abnormal uterine growth. Falling hCG levels may indicate the possibility of a miscarriage. hCG levels which are rising at a slower rate than expected may indicate an ectopic pregnancy.