More about HCG
Q: Why do HCG levels fluctuate so much?
A: The answer is complex. Most experts theorize that the reason for change in HCG levels is that--at a certain point in the pregnancy--the placenta takes over making the hormones estrogen and progesterone. This means HCG is no longer needed to stimulate the ovary to make hormones, says Dr. Ross. Again, it's at the beginning of your pregnancy that your HCG levels are especially crucial. Those levels help your doctor determine whether or not your pregnancy is a healthy one. But keep in mind that even if you're bleeding at the beginning of pregnancy, it's a healthy pregnancy if your HCG number doubles.
Q: What can my doctor tell from my HCG levels?
A: Because the normal range is so great, it's often hard to tell much about a pregnancy from just one HCG measurement, according to Dr. Hakakha. Doctors can, however, can gain information from looking at trends. A normal pregnancy has HCG levels that double every 48 hours. Although there are exceptions, HCG levels that rise at a lower rate, and then plateau or even decline, often indicate an abnormally developing pregnancy or an ectopic pregnancy, one that exists outside of the uterus.