How Does a Pregnancy Test Work?

This may not be the first question you think of when you believe you might be pregnant and are looking for a test. Questions like, “How reliable is this test?” or “Is it too early to take a pregnancy test?” probably come to mind sooner. But understanding how a pregnancy test works can help answer both of those questions and give you confidence in the results.

So what exactly does a pregnancy test, test? Pregnancy tests are looking for a hormone called Human Chorionic Gonadotropin. That’s a mouthful, so it is commonly referred to as hCG and is secreted by the placenta during pregnancy. Let’s break that down.

Human – pretty straightforward. It comes from humans, not other animals, droids, cyborgs or aliens. This specific hormone is produced by humans during pregnancy.

Chorionic – This comes from the word Chorion, one of the membranes that develop between the mother and the fetus during pregnancy. Embyro is a scientific term for a specific stage or development in a mammal from conception to 8 weeks. In this case, we are talking a human embryo. After that, it is referred to as a fetus up until birth. Then an infant, toddler, teenager, etc. The term fetus isn’t referring to a stage where the baby is something else, but a specific stage of development.

Gonadotropin – This is a protein hormone that helps regulate growth and is important for the development of the baby during pregnancy

So Human Chorionic Gonadotropin (hCG) is simply a hormone that is produced as a human baby develops.

The pregnancy test measures the amount of hCG in a woman’s urine (or blood if a blood test is used) to determine if she is pregnant. On average, a non-pregnant woman will have less than 5mlU/ml of hCG present in her urine. However, a few weeks after implantation happens the amount of hCG her body secrets doubles every 48-72 hours. So a pregnant woman’s body has drastically more HCG than a non-pregnant woman’s body. If there is enough hCG present (how much depends on the sensitivity of the test), you get a positive result.

Pregnancy tests are calibrated at different levels, and thus some are accurate earlier in the pregnancy than others. Most tests are set to detect levels of hCG at 20 mlU/ml, 50 mlU/ml, or 100 mlU/ml. The lower the number, the earlier the test can determine pregnancy. By 7 days post ovulation, a pregnant woman can have up to 50 mlU/ml of hCG in her blood. A test that is highly sensitive (20mlU/ml) will be accurate for most, but not all women, by 7-10 days after possible conception.

If you do take a test this early, it is possible that a test can come back with a false negative, meaning the result you got was negative but you are actually pregnant. This can happen if ovulation occurred later than you think, or if you have a lower hCG production level than average. If you do decide to take a test as early as 7-10 days and get a negative result, we recommend you take another test a few days later just to be sure.

At Collage, we offer complimentary pregnancy and STD tests as well as a trained patient advocate who you can talk with about your options if the test does come back positive. We typically test either after a missed period or 10 days after possible conception to better ensure an accurate test result. Feel free to call or email us if we can help you or a friend.

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Understanding Abortion Pills: What to Know

July 21, 2026

If you're considering the abortion pill, knowing what it actually involves is an important first step as you weigh your decision. Schedule a free, confidential appointment at Collage to talk through your questions and get accurate information at no cost. How the Abortion Pill Works The abortion pill uses two drugs taken at different times. Mifepristone , the first, blocks progesterone, a hormone the body needs to maintain a pregnancy. Without it, the pregnancy stops developing. The second drug, misoprostol , causes the uterus to contract and expel the pregnancy. Risks and Side Effects Cramping and bleeding are expected parts of the process. Additional side effects can include fever, chills, nausea, vomiting, diarrhea, and headaches. Complications include: Incomplete abortion (pregnancy tissue remaining in the uterus) Heavy bleeding that does not stop Infection Without in-person medical care, distinguishing normal symptoms from those requiring urgent attention is difficult. Why Gestational Age and Pregnancy Location Matter The FDA approved the abortion pill through 10 weeks of gestation. It is important to know how far along you are for your health and safety as you move through making your next decisions. A limited OB ultrasound also screens for ectopic pregnancy , a pregnancy outside the uterus that the abortion pill cannot treat and requires urgent care. A positive test alone does not rule out an ectopic pregnancy or miscarriage , since hCG can remain elevated after pregnancy loss. Getting the Full Picture Collage offers free pregnancy testing and limited OB ultrasounds to give you the medical details you need before deciding anything, whether you're considering parenting, adoption, or abortion. Schedule your free, confidential appointment at Collage today. Kindly call the numbers for the branch nearest to you: Kearney: (308) 234-9880 Grand Island: (308) 675-2217 All abortion information sourced in this blog is based on accurate information at the time of writing. Collage does not provide or refer for abortions; however, we do offer pre-abortion screening through our no-cost services.

Why Does an Ultrasound Matter Before an Abortion?

June 28, 2026

If you're considering abortion, there's one medical step that protects your health before anything else. An ultrasound confirms your pregnancy and provides information that a positive test alone cannot.

How Does Abortion End My Pregnancy?

May 29, 2026

If you’ve recently learned you are pregnant unexpectedly, we understand how overwhelming this might feel right now. If you're considering abortion as an option, taking time to understand how the process works is important so you can make an informed decision. Collage is here to help provide you with confidential support and abortion information at no cost. We offer a safe space, free of judgment, where you can think calmly about your options, receive lab-quality pregnancy testing, and get a complimentary ultrasound so you can get the facts around your pregnancy and learn what options are available to you. Schedule your free appointment today. Medical Abortion Medical abortion, also known as the abortion pill, ends a pregnancy by using two drugs taken at different times. The first pill, mifepristone, works by blocking progesterone and causes the embryo’s death. The second drug, called misoprostol, is usually taken a day or two after and causes the uterus to contract, expelling the pregnancy tissue through cramping and bleeding. Common side effects can include bleeding and cramping, bleeding with blood clots, and a low-grade fever. Medical abortion is only approved through ten weeks of gestation by the FDA . Follow-up care is typically recommended after a medical abortion to make sure the process is complete. Surgical Abortion Surgical abortion terminates a pregnancy in a clinic or medical setting and involves removing pregnancy tissue from the uterus through a suction device or a tool called a curette. This can also be called dilation and evacuation or dilation and curettage . Common side effects of surgical abortions are bleeding and cramps. You may also have a late or early period as your uterus has to build a new lining after the procedure. What Are The Risks Of Abortion? Medical and surgical abortion both have possible risks that you should be aware of. Some women may also experience emotional responses afterward. Complications that can arise from abortion are: Infection. Scar tissue on the uterine wall, known as Asherman's syndrome . Heavy bleeding that may not stop. Diarrhea and digestive pain. An incomplete abortion. Confirm Your Pregnancy With An Ultrasound Before making a pregnancy decision, it is important to verify your pregnancy with an ultrasound. An ultrasound provides important medical details such as how far along you are, the location of the pregnancy, and whether a heartbeat is detected. These details are important since the abortion pill is not FDA-approved for over ten weeks, and it also rules out ectopic pregnancy, which requires urgent medical attention. As many as 26% of all pregnancies end in a miscarriage, and you can still get a positive pregnancy test result for days or weeks after a miscarriage because it takes time for hCG to leave the body. An ultrasound will confirm whether or not you have miscarried. We provide no-cost pregnancy services at our center, including limited OB ultrasounds, so you can get informed about your pregnancy and options. Get Pregnancy Support at College If you're considering your next step after learning you are unexpectedly pregnant, we are here to give you a safe place to ask questions and learn more about your options. Collage provides confidential appointments and no-cost pregnancy services, including medical-grade pregnancy testing, ultrasounds, and STD testing . You don’t have to figure this out alone. We are here to listen. Schedule your free confidential appointment to learn more about your options. Collage does not provide or refer for abortions; however, we do offer pre-abortion screening through our no-cost services.