hCG is the pregnancy hormone that is produced by the placenta as early as 3-4 days after implantation. The blood hCG level doubles every 2-3 days until it reaches a level of about 1,200 mIU/cc, the increase then slows down to a much slower doubling, and after 10-12 weeks the hCG drops to lower levels.

The hCG drops normally around 10-12 weeks of the pregnancy and then stays stable for the rest of the pregnancy.

The hCG normally drops after 10-12 weeks of your pregnancy. The doubling of the HCG only applies to early pregnancy, up to an hCG of initially 1,200 mIU/ml, then to about 6,000 mIU/ml.

After that time, the hCG rises much slower, and at 10-11 weeks it normally drops. A good fetal heartbeat after 6-7 weeks is the best indication that the fetus is doing well and there is no more need to do the hCG after that time.

HCG hormones can also be used as part of a diet plan in order to lose weight.  The HCG diet which includes hCG in drops usually involves a low-calorie diet as well as daily doses of HCG drops. The HCG diet originally depended upon regular injections of HCG, but homeopathic HCG drops are now available that can be used while dieting in order to promote weight loss.

Pregnancy can affect the use of HCG drops and it's recommended to not use hCG drops when pregnancy is possible. It is usually advisable to begin the HCG drops after the end of your menstrual period, when you are sure you are not pregnant, although it is possible to continue with the HCG drops should menstruation occur halfway through the diet protocol.

It is advisable to use birth control to prevent pregnancy effectively when you take hCG drops. HCG drops can be taken while menstruating, although they may cause the period to become heavier than usual. The drops should not be taken anymore if they cause discomfort during menstruation until the period has ended.