What Is a Pregnancy Test?
It goes without saying, but a pregnancy test is a medical tool that checks if you are pregnant. Pregnancy tests work by analyzing your urine or blood for a hormone called HCG, also known as human chorionic gonadotropin.
Women produce HCG when they’re pregnant. HCG is released in the body when a sperm fertilizes an egg. Your body produces this compound shortly after you become pregnant, usually about 10-days after the egg is fertilized by sperm. HCG production typically doubles every couple of days during the early stages of pregnancy. However, a pregnancy test taken too early may not detect the presence of HCG, even if you are pregnant.
There are two types of pregnancy tests, both of which are effective at detecting HCG:
Blood tests are usually taken at a doctor’s office. A urine test can also be taken by a doctor but is available over the counter to be taken at home and can be purchased at most pharmacies. You don’t need a prescription to purchase an over-the-counter pregnancy test, and there are several different urine tests you can choose from. However, all tests essentially do the same thing.
How Do You Take a Pregnancy Test?
There are different methods for taking a pregnancy test.
First, if you’re taking a blood test, your doctor will draw a small amount of blood into a test tube and send it to a lab to check for HCG. Urine tests are most frequently done at home, although your doctor may also conduct one.
Depending on the particular home test, you may have to:
- Urinate on a small test strip over your toilet bowl
- Collect your urine in a cup and dip a small test strip in the fluid
- Collect your urine, then use an eyedropper to place a small sample onto a test strip
Keep in mind, all home tests will contain step-by-step instructions on the packaging, so be sure to follow the directions for your particular test.
After you take the test, you will have to wait while it analyzes your urine for HCG. When the test is complete, it should display your results. The display for a positive result will differ between products, although some of the more common displays include:
- A change in color
- The appearance of a line
- A plus or minus symbol
- The words “pregnant” or “not pregnant”
These tests vary in how long you have to wait and how they indicate their result. It’s important to carefully read the instructions to ensure you use these at-home kits properly.
How Accurate Are Pregnancy Tests?
Some of the most common conditions that can occur in the bladder include:
- Bladder Cancer
- Cystitis (inflammation of the bladder caused by infection)
- Interstitial Cystitis (a chronic bladder inflammation that causes pain and an urgent need to urinate)
- Overactive Bladder (involuntary and frequent urination)
- Stress Urinary Incontinence (such as peeing when you sneeze)
Thankfully, all of these conditions can be treated by your doctor. Your doctor will use a range of tests to diagnose your condition, which may include urine analysis, x-rays, or an internal scope called a cystoscope. Once you have a diagnosis, the physician will recommend the appropriate treatment or home remedy to help your issue.
When Should You Take a Pregnancy Test?
Doctors usually recommend you wait until you’ve missed your period before taking a pregnancy test. So, if your period normally comes on the 15th of the month and doesn’t arrive on time, consider seeing your gynecologist or taking an over-the-counter test.
It can be challenging for those of us who have irregular periods since missed periods can happen even when we aren’t pregnant. Even so, if you feel that there is a chance you may be pregnant, it’s important to have a test on hand just to be sure.
If your test is negative and you still haven’t had a period, repeat the test a week later. If you continue to miss your period and still show negative results, consider seeing your doctor.
Here are a few simple tips for ensuring a more accurate at-home pregnancy test:
- Take a urine sample first thing in the morning after you wake up—early morning urine typically contains higher concentrations of HCG
- Avoid drinking excessive amounts of fluids before the test (it can dilute your urine sample)
- Read all of the instructions carefully
A pregnancy test searches your urine or blood for the HCG chemical. However, it takes about 10-days after becoming pregnant before your body begins to produce these hormones. Because of this, taking a pregnancy test too early can result in a false negative.
Other complicating factors include taking fertility drugs that contain HCG, which can produce a false positive. Menopause can also skew the results.
Common causes of a false negative on an at-home pregnancy test include:
- Taking the test too early
- Failing to follow the test instructions
- Using diluted urine from later in the day
Signs that indicate you should probably take a pregnancy test include:
- Missing a period
- Irregular bleeding
- Breast pain
- Nausea or an aversion to food
- Frequent urination
- Pelvic pain
- Your birth control failed (you forgot to take a pill or the condom broke)
All of the above are common signs of pregnancy that can also be caused by other conditions—taking a pregnancy test may clarify why you’re experiencing these symptoms.
As the weeks progress, these symptoms may also increase. If you conduct an at-home test and receive a positive result, it’s time to see a doctor and discuss your pregnancy options.
Women First of Louisville is an obstetrics and gynecological practice devoted to keeping women healthy at all stages of their reproductive life. Talk with our team today to find out how we can help.