Human Chorionic Gonadotropin (hCG) Levels Explained

Human chorionic gonadotropin, or hCG for short, is often referred to as “the pregnancy hormone” because it’s present in large quantities during pregnancy. And it is, after all, the hormone that many at-home pregnancy tests are designed to detect! Find out more about what hCG is, when it’s detectable by at-home pregnancy tests, and what the typical hCG levels are for each of the early weeks of pregnancy.

What Is hCG and When Does Your Body Start Producing It?

Human chorionic gonadotropin (hCG) is known as the pregnancy hormone, as your body produces it in large amounts when you’re pregnant.

Although you can have low levels of hCG in your body at any time, the levels of this hormone tend to rise sharply early on in your pregnancy for two reasons:

1. About 10 days after conception, the fertilized egg attaches to the lining of your uterus and your body starts to make hCG. Over the next week or so, hCG levels will increase.

2. At about 4 weeks pregnant, the egg—now called an embryo—implants further into the uterus and begins to produce even more hCG, which triggers increased productions of other hormones like estrogen and progesterone.

Together, these hormones help build the lining of the uterus and send signals to the ovaries to stop releasing eggs, ultimately stopping your period.

During these early weeks of pregnancy, you may not show any outward signs of being pregnant and you may not even suspect that you’re pregnant! You may, however, experience implantation bleeding when the fertilized egg attaches to the lining of the uterus (as described above). This is normal and may resemble spotting or a light period.

When Can Pregnancy Tests Detect hCG?

Home pregnancy tests often work by detecting hCG in your urine. All of these over-the-counter pregnancy tests work a little differently, so check the instructions in or on the box. Keep in mind that hCG levels increase over time, so at-home tests are more accurate as your pregnancy progresses. Therefore, a home-pregnancy test that’s taken too early might not detect low levels of hCG and could produce a false negative, meaning the result is negative when you’re actually pregnant. If you’re wondering when to take an at-home pregnancy test, try one of the following timelines:

• You might try taking a pregnancy test about three to four weeks after the first day of your last period, as this is when the levels of hCG in your urine will have increased enough to be detectable.

• You could wait until around the time you miss your next period, which could be the initial clue that you may be pregnant anyway! By then, the levels of hCG are detectable.

A blood test is the most accurate way to detect hCG levels, because more of the pregnancy hormone is present in the blood than in the urine. Plus, blood tests need less of the hCG hormone to detect a pregnancy, as explained below:

• Blood tests. Pregnancy blood tests can detect hCG hormone levels as low as 5 to 10 mIU/mL.

• Urine tests. At-home urine tests require higher levels of hCG to detect a pregnancy, typically at least 20 mIU/mL.

If your home pregnancy test is positive, your healthcare provider may offer a blood test to check your hCG levels. The results can help your provider confirm your pregnancy and determine how far along you are.

If you’ve just found out you’re pregnant, you can get an estimate of your due date with our Due Date Calculator using either the date of conception or the date of the first day of your last menstrual period!

hCG Levels Chart by Week

The week-by-week chart below will give you an idea of how your hCG levels may rise during the first trimester, and then dip slightly during the second trimester. Keep in mind that, if you want your hCG blood test results explained in more detail, your healthcare provider is the best person to ask.

What Does It Mean if You Have High or Low hCG Levels?

It’s important to remember that every pregnancy is different, and you may have lower or higher levels of hCG hormone than what’s indicated in the week-by-week chart above. Most likely, there’s no cause for concern, but your healthcare provider will help you understand what these levels mean.

Low Levels of hCG

Low levels of hCG are normal for non-pregnant women and men. Normally, hCG levels would be less than 5 mIU/mL and less than 2 mIU/mL, respectively, for these groups. If you’re pregnant and experience low hCG levels, it’s important to look at your entire pregnancy as a whole. Your healthcare provider will consider all the factors of your pregnancy to determine why you might be experiencing lower-than-normal levels of hCG. If your provider suspects anything like an ectopic pregnancy, they may perform additional tests to rule it out.

High Levels of hCG

Likewise, high levels of the hCG hormone might not indicate anything out of the ordinary. However, a higher-than-normal level of hCG may be a sign that you’re having twins or triplets! Again, your healthcare provider will work with you to determine an appropriate course of action, if any is needed. Lower- or higher-than-normal levels of the hCG hormone during your pregnancy might not indicate anything unusual. However, it’s always a good idea to follow up with your healthcare provider as a precaution, regardless of any questions or concerns you have. Read more about other pregnancy symptoms not to ignore.

The Bottom Line

The hCG hormone plays an important role in your pregnancy, and the changing levels of this hormone are just one of many transformations your body will experience as your baby develops. Although hormonal changes can make you feel a little off from time to time during your pregnancy, try to take these as reassurance that your baby is growing, and you’re getting closer and closer to the day you finally get to meet them. In the meantime, prepare for your baby’s arrival and get rewards on all your diapers and wipes purchases with the Pampers Club app! Ready to share your pregnancy news with friends and family? Get creative pregnancy announcement ideas in the video below!