How Does a Pregnancy Test Work?

May 25, 2015

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.

July 2, 2025
If you’re in your second trimester (between 13 and 26 weeks of pregnancy), you might be asking, What now? Maybe you just found out you’re pregnant, or maybe this stage of pregnancy is bringing new questions or emotions. No matter where you are in your journey, Collage is here to offer support, information, and a safe place to talk through your options. Understanding Abortion Laws in Nebraska In Nebraska, abortion is not permitted after 12 weeks gestation, with limited exceptions. If you’re considering abortion and believe you may be near or past this point, it’s important to have an ultrasound to confirm how far along you are. If you’re unsure how far along you are, Collage offers no-cost lab-quality pregnancy testing and ultrasounds to provide the medical information you need to understand your next steps. Exploring Your Other Pregnancy Options If abortion is not an option or you’re unsure what’s next, you still have choices. We can talk with you more about each of them. Parenting Parenting might feel like something you’re not ready for or even impossible right now. But with the right support, it may be more achievable than you think. You don’t have to have all the answers today. At Collage, we can connect you with local resources, parenting classes, and support systems that can help you prepare, step by step. You won’t be alone. Adoption If parenting doesn’t seem like the right fit for your current season, adoption is another option that gives you the ability to make a thoughtful plan for your child. Today’s adoption process puts you in control of key decisions, including:  Choosing the adoptive family Deciding how much (if any) communication you’d like to have Creating a plan that reflects your goals and values We offer adoption referrals and a confidential space to explore what this might look like for you—no pressure, just information and support. You’re Not Alone Navigating pregnancy in the second trimester can feel heavy, but you don’t have to walk through it by yourself. At Collage, you’ll find compassionate care, medical services, and honest answers to your questions. Schedule your no-cost appointment today. We’re here to listen and support through this process.
June 4, 2025
An unexpected pregnancy can leave you with more questions than answers. Especially when friends are urging you to choose abortion, you may be more confused than ever. While their advice might come from care or fear, it’s essential to remember this is your pregnancy, future, and choice. At Collage, we’re here to help you navigate this pressure and find a path that feels right for you so that you can feel informed and confident about your decision. Reach out to us today for no-cost support. Listen to Your Instincts Your friends might be an important part of your life, but your instincts matter most. If abortion doesn’t feel right, take a moment to ask: What’s holding me back? Maybe you’re picturing parenting your child or are curious about adoption. It’s also important to keep in mind that abortion is a serious procedure that your friends may not fully grasp the details of. Physical and emotional risks are involved, making it a more complex decision. Your hesitation is a sign to slow down and explore, not to rush into a choice you’re not ready for. Talk It Out If your friends keep pressing, try a gentle conversation. Let them know you understand they’re worried, you’re not sure about abortion yet. Ask what’s driving their advice. Maybe they’re scared about your finances or future. Maybe they’re simply telling you what they’d do in your situation, but that doesn’t mean it’s right for you. Understanding their side can ease tension without giving in. If they won’t respect your space, set boundaries and let them know you need time to think. You don’t owe them an immediate answer. Find Your Support Surround yourself with people who’ll lift you up, not pull you down. Write down your thoughts or talk to someone neutral. You can find a counselor or even online spaces where you can share your heart with those who won’t push one option over another. Even a trusted family member, a mentor, or a place like Collage can offer perspective without strings. You deserve to make this decision with clear facts and a steady heart, not under pressure. Help is Available If your friends are pushing abortion but you’re not ready, Collage is here with no-cost lab-quality pregnancy testing, limited obstetric ultrasounds, and pregnancy options education to help you decide what’s next. Our trained team offers confidential support to explore parenting, adoption, or abortion without pressure. Contact us for a no-cost appointment today. You deserve to choose your own path.
May 21, 2025
An unexpected pregnancy can flip your world upside down, and the urge to keep it under wraps might hit hard. Maybe you’re thinking abortion could erase the situation quietly.
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