The Significance Of Pregnancy Hormone Levels
Human chorionic gonadotropin (HCG) is called the pregnancy hormone because it is produced during pregnancy. The pregnancy hormone level rises very early in pregnancy, and HCG can usually be detected in the blood within eleven days after conception.
The HCG level continues to rise as the pregnancy progresses and peaks somewhere around nine to twelve weeks, slowly declining after that. The level remains elevated until the pregnancy ends, and then it drops rapidly back to normal.
Sometimes, pregnancy hormone is given by injection to women who are undergoing fertility treatment in order to help an embryo implant in the uterine wall. This will, of course, result in abnormal HCG levels.
Normal Pregnancy Levels
There are wide variations in normal pregnancy hormone levels. The actual numerical level is not as important as the direction of change. For this reason, the level will usually be checked at least twice, a couple of days apart.
Low Pregnancy Hormone Levels
After an initial pregnancy hormone level to confirm the pregnancy, physicians don't usually recheck the level. Sometimes, however, they will recheck the HCG level if there is bleeding, pain or other indications of a problem with the pregnancy.
Low HCG levels may simply mean the pregnancy is not as far along as you thought it was. Pregnancy hormone levels are also low with a miscarriage or an ectopic pregnancy. The doctor may check your pregnancy hormone level more than once to see if it is rising or falling. A rising level suggests a date miscalculation; a falling level suggests that the pregnancy is not sustainable.
High Pregnancy Hormone Levels
Again, an unexpectedly high pregnancy hormone level may simply indicate a date miscalculation. You may be further along than you thought you were. Physicians are likely to check HCG levels if they suspect a multiple pregnancy or a molar pregnancy.
Molar pregnancies occur when an egg is fertilized but chromosomal abnormalities result. The fertilized egg may grow—it may grow rapidly—but it is a cluster of cells or a growth, not a fetus.
The presence of pregnancy hormone indicates that you are pregnant (unless you are receiving HCG injections for fertility treatment). Abnormal trends in the pregnancy hormone level may help the physician determine if there is a problem with the pregnancy. The exact number of HCG is less important than whether it is rising or falling normally.