Pregnancy tests for home use

Can you be pregnant? Answers to frequently asked questions about pregnancy tests.

Taking a pregnancy test can be exciting, but also stressful. That's especially true if you're not sure whether to trust the results. Know when and how to take a home pregnancy test. And learn about the possible disadvantages of testing at home.

When should I take a pregnancy test?

Many home pregnancy tests claim that you can tell if you are pregnant on the first day of a missed period. Some tests even claim that you can do them before then. But the results of a pregnancy test are likely to be more accurate if you take the test after the first day of the missed period. That's because shortly after a fertilized egg attaches to the uterine lining – a process called implantation – the placenta begins to form. The placenta produces the pregnancy hormone human chorionic gonadotropin (HCG). HCG can be found in blood and urine. HCG is only present in the body during pregnancy.

A home pregnancy test checks whether there is HCG in the urine. During early pregnancy, the amount of HCG in blood and urine increases rapidly – doubling every 2 to 3 days. That means that if you wait a day or two after your missed period to take the test and you are pregnant, the test is more likely to find HCG and give a positive result.

The timing of ovulation makes a difference in the accuracy of a pregnancy test. And ovulation can vary from month to month. A fertilized egg can also implant in the uterus at different times. This can affect when HCG is produced and when it can be found with a pregnancy test. Irregular menstrual cycles can also affect pregnancy test results because it makes it difficult to determine when a period should begin.

How do I use a pregnancy test?

With most home pregnancy tests, you place the end of the test in your urine stream, dip the test in a container of urine, or put a few drops of urine on the test. A few minutes later the result appears. This is often a plus or minus sign, the words “yes” or “no”, one or two dashes, or the words “pregnant” or “not pregnant”.

Make sure you follow the test instructions for how long to wait before checking the results. Usually that is two minutes or more. Most tests also have a control indicator. That's usually a line or some other symbol that you can see in the results window. If you don't see that line or symbol, the test isn't working. Try again with another test.

Some pregnancy tests are more sensitive than others. More sensitive tests require less HCG in the urine to get a positive result. If you're not sure which type of test to use, ask a pharmacist.

Always check the test expiration date. If it has expired, do not use it. Read and follow the directions for the test carefully.

How accurate are home pregnancy tests?

Many home pregnancy tests claim 99% to be accurate. But home tests differ in their ability to find a pregnancy in people who have recently missed a period. If the test result is negative but you still think you could be pregnant, take another test a week after the missed period or contact your doctor.

Can medications change test results?

Fertility medications or other medications containing HCG can affect pregnancy test results. However, most medications, including antibiotics and birth control pills, do not affect the accuracy of pregnancy tests.

Can a positive result be wrong?

That's rare. But it is possible to get a positive result from a pregnancy test even though you are not pregnant. This is called a false positive result.

You can get a false positive test if you have lost a pregnancy shortly after the fertilized egg has attached to the uterine lining. You can also get a false positive result if you take a pregnancy test soon after taking a fertility drug that contains HCG. Problems with the ovaries and menopause can also lead to a false-positive test result.

Can a negative result be wrong?

It is possible to get a negative result from a pregnancy test if you are pregnant. This is known as a false negative. You can get a false negative result if you:

• Take the test too early. The earlier you take a pregnancy test, the harder it is to find HCG. For the most accurate results, take a pregnancy test after the first day of a missed period.
• Check test results too early. Set a timer to go off when the instructions tell you to check the result. Do not check the test until that time has passed.
• Take the test later in the day. For the most accurate results, take the test right after you get up in the morning. This is when your urine is most concentrated, making HCG easier to find.

What happens now?

Based on the test results, consider the following steps:

• Your pregnancy test is positive or you have taken a few pregnancy tests with varying results. Make an appointment with Midwives Lelystad. You may need a blood test or ultrasound to confirm the pregnancy. The sooner the pregnancy is confirmed, the sooner prenatal care can begin.
• Your pregnancy test is negative. If you miss your period, take the test again in a few days or a week. It is especially important to do this if you took the test before or just after a missed period.

Midwives Lelystad