How Do Pregnancy Tests Work?

August 13, 2025

If you’ve taken or are considering taking a pregnancy test, you may wonder how it works. It’s completely normal to have questions, especially when facing something unexpected. Learning about the process can ease any anxiety and help you feel more prepared for whatever comes next.

Heart to Heart provides confidential services to help you navigate moments like this. Schedule an appointment today for a free pregnancy test. 

Keep reading to learn more about how pregnancy tests function.

What a Pregnancy Test Is Looking For

Pregnancy tests detect a specific hormone called human chorionic gonadotropin, or hCG. This hormone starts to build in your body once a fertilized egg implants in your uterus. As the pregnancy continues, the amount of hCG in your body increases significantly.

As hCG levels rise over time, taking a pregnancy test too early might lead to an inaccurate result. That’s why it’s best to wait until after your missed period, when the hormone is more likely to be detectable.

Types of Pregnancy Tests and What to Expect

There are two kinds of pregnancy tests: urine-based and blood-based.

Most people start with a urine test, which can be performed at home or in a clinic. These tests are fast and convenient, and they check for hCG in your urine. While generally accurate, they can produce a false negative if taken too soon or improperly.

Blood tests are more sensitive and typically done at a medical facility, like a doctor’s office or hospital. They can detect a pregnancy earlier and are sometimes used to measure hCG levels over time. This type of testing is often used for specific medical situations, such as when there’s a risk of miscarriage.

Finding the Right Time to Test

Everybody is different. If your periods are irregular or you’re unsure when to test, speaking with a medical professional may be helpful. Additionally, testing first thing in the morning, when hCG is most concentrated in your urine, may also improve the accuracy of your result.

Heart to Heart offers no-cost pregnancy tests in a calm, supportive environment. If your test is positive, our nurses will provide a limited obstetrical ultrasound to confirm the pregnancy and offer essential next steps.

You’re Not Alone

Facing a possible pregnancy, especially an unexpected one, can feel overwhelming. However, you don’t have to navigate this alone. We’re here to offer clear answers and confidential services so you can move forward.

Schedule your free appointment today. We’re here for you, every step of the way.