What is HCG?

• HCG (also known as human chorionic gonadotropin) is a hormone that is produced only during pregnancy. The hormone is constructed of cells used to form the placenta. HCG is released into the body once the fertilized egg has attached to the wall of the uterus.
  
  

Detecting HCG

• HCG can be detected by a blood test at approximately 11 days past ovulation. This is the most accurate way to confirm pregnancy. The hCG hormone can also be detected through urine by using a pregnancy test. The best time to use a pregnancy test is the day after a woman has missed her period. If hCG is present, the test will show a positive result.
  
  

Normal Levels

• Normal levels of hCG will vary with each person. However, to be considered pregnant, the level of hCG must be greater than 5 mIU/ml. A good guideline is that a pregnant woman's hCG level should double every 48 to 72 hours. One way to tell if the levels are doubling is by repeating a pregnancy test. If the positive line is darker than the original test, the level of hCG in the body has increased. However, the best bet to make sure that the hCG levels are normal is to consult a physician.
  
  

High hCG = Multiples

• A common indicator for multiples such as twins is a higher hCG hormone level. This is because there is more than one fertilized egg (also known as a embryo) and therefore the amount of hormones produced is greater than a single embryo pregnancy.
  
  

HCG and Miscarriages

• When a miscarriage is imminent, the levels of hCG found in the body will rapidly decrease. If a miscarriage is suspected, the physician will order a blood test to determine the current level. A repeat blood test will be preformed several days later to confirm that the hCG levels are continuing to decrease and will advise his patient about the options available. Once a miscarriage has occurred, the body will reduce the level of hCG to less than 5 mIU/ml within four to six weeks.