Using an HCG Calculator to Monitor Pregnancy Hormones

Crystal Schwanke
Reviewed by RDMS Julie Kirk
Image of a postive pregnancy test

An HCG calculator will detect if you are pregnant and determine whether the HCG levels in your blood are increasing as they should early in the pregnancy. HCG, human chorionic gonadotropin, is the hormone made by the placenta soon after the fertilized egg implants.

HCG Levels

For the first few weeks of pregnancy, the HCG levels should more than double every two days. Around the beginning of the second trimester, HCG levels usually level out and remain that way for the duration of the pregnancy. When you are pregnant, your HCG level is at least 25 mIU/ml. When you are not, the level is less than 5 mIU/ml.

What Is an HCG Calculator?

HCG calculators ask you to enter your first HCG level, how many days past ovulation you are (this step isn't necessary, but it is helpful), your second HCG level, and how many hours/days you waited between those tests. Once those are entered, you will get feedback about whether the increase is adequate. In some cases, the HCG calculator includes a chart that allows you to monitor the increase and how it compares to low, average, and high levels.

Blood Tests

You'll need a blood test to determine exactly where your HCG level is. Since HCG calculators need two numbers, you'll have to get those from your doctor. Pregnancy tests do tell you if the hormone is present in your urine at a high enough level to mean you're pregnant, but they don't tell you just how high your HCG level is. So while you'll know you're pregnant, you won't be able to chart the progression of your doubling levels without your doctor's assistance. Unless you have a high-risk pregnancy or seem to have a problem, they may not routinely check your HCG.

Using an HCG Level Calculator

At Baby Med, you can find an HCG calculator that not only tells you the adequacy of the increase, but you'll get a further breakdown that includes:

  • Your total HCG increase
  • The HCG doubling rate
  • The two day increase
  • A chart that shows minimum, average, and maximum rates and where your HCG levels fall in the mix

If you visit the Just Mommies HCG calculator, you'll get a quick and easy look at how rapidly your HCG level is shifting. Simply enter in your first and second HCG levels along with how long you waited between tests. You'll get information as to how many hours and days it takes for your levels to double.

What the Numbers Can Mean

High and low numbers may be concerning, but they don't always mean problems. However, it's always best to discuss with a doctor if you are worried.

Low Numbers

If your HCG calculator shows that your levels are on the low end of the spectrum, slowly rising, or dropping, it could mean:

High Numbers

If your HCG calculator shows that your levels are higher than expected, it could mean:

  • Your pregnancy began earlier than originally thought
  • You are carrying multiples
  • Molar pregnancy (genetic error that occurs when the egg and sperm join, resulting in an abnormal growth of tissue inside of the uterus)

Visit Doctor When Concerned

Don't put too much weight on your HCG levels. An ultrasound will reveal more reliable information about the pregnancy. Women can have HCG levels that increase at varying rates, all with perfectly normal, healthy pregnancies. However, if you are concerned, it is best to speak with your doctor.

Importance of Your HCG Levels

The HCG calculator is an interesting tool used to chart and monitor the increasing levels of the HCG hormone. It can be used as an important indicator for many things, from an ectopic pregnancy to multiples, but remember that the numbers fluctuate from woman to woman and that you can always contact your doctor for further evaluation.

Using an HCG Calculator to Monitor Pregnancy Hormones