Human chorionic gonadotropin facts for kids

Human chorionic gonadotropin (hCG) is a special hormone that the body makes, mainly during pregnancy. Think of hormones as chemical messengers that tell different parts of your body what to do. hCG plays a very important role in helping a pregnancy continue.

This hormone is often called the "pregnancy hormone" because it's what most pregnancy tests look for. If hCG is found in a test, it's usually a sign that someone is pregnant.

What is hCG?

hCG stands for Human chorionic gonadotropin. It's a type of protein hormone. It's made by cells that will eventually form the placenta. The placenta is an organ that grows in the uterus during pregnancy. It provides oxygen and nutrients to the growing baby and removes waste products.

When does the body make hCG?

The body starts making hCG very soon after a fertilized egg attaches to the wall of the uterus. This usually happens about 6 to 12 days after fertilization. The levels of hCG quickly rise in the first few weeks of pregnancy. They usually double every 2 to 3 days!

Why is hCG important in pregnancy?

hCG has several key jobs during pregnancy:

• Maintaining the pregnancy: One of its most important jobs is to tell the body to keep producing another hormone called progesterone. Progesterone is vital for keeping the lining of the uterus thick and healthy, which is where the baby grows.
• Preventing menstruation: hCG helps stop the normal menstrual cycle. This means the body doesn't shed the uterine lining, which is necessary for the pregnancy to continue.
• Supporting the early baby: It helps the very early stages of the baby's development by supporting the corpus luteum, a temporary structure in the ovary that produces progesterone.

How do we test for hCG?

Doctors and people at home can check for hCG levels using simple tests.

Urine tests

These are the most common type of pregnancy tests, often bought at a pharmacy. They work by detecting hCG in a person's urine.

• How they work: The test strip has special chemicals that react with hCG. If hCG is present, a line or symbol appears on the test, showing a positive result.
• When to use them: These tests can usually detect pregnancy about a week after a missed period.

Blood tests

Blood tests for hCG are done by a doctor or in a lab. They are more sensitive than urine tests.

• How they work: A small sample of blood is taken, and the lab measures the exact amount of hCG in it.
• Why they are used: Blood tests can detect pregnancy earlier than urine tests, sometimes as early as 10 days after conception. They can also measure how much hCG is present, which can help doctors understand how the pregnancy is progressing.

Other uses of hCG

While hCG is mostly known for pregnancy, it can also be used in other ways:

• Fertility treatments: Sometimes, hCG is used as a medicine to help people who are trying to get pregnant. It can help trigger the release of eggs from the ovaries.
• Certain medical conditions: In some rare cases, certain types of tumors can produce hCG. So, doctors might test for hCG to help diagnose or monitor these conditions. However, this is much less common than its use in pregnancy.

Summary

hCG is a fascinating hormone that plays a central role in pregnancy. It's the reason why pregnancy tests work and helps ensure a healthy start for a developing baby. Understanding hCG helps us learn more about how the human body works during this amazing time.

See also

• In Spanish: Gonadotropina coriónica humana para niños