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If you’re trying to conceive, you may wonder how soon after ovulation you can take a pregnancy test.
Women are often advised to wait until missing a period to take a home pregnancy test, but there are options that offer earlier results. So why not find out sooner rather than later? There are pros and cons to taking pregnancy tests early. Here’s what to expect.
How early can you take a pregnancy test?
Some home pregnancy tests are sensitive enough to detect pregnancy hormones up to six days before a missed period. That means if you have a 28-day menstrual cycle, you can test around days 22–23, which is 8–9 days past ovulation if you’re pregnant (FDA, 2018).
However, there is a trade-off to testing early. When performed early, some home pregnancy tests claim to be around 70% accurate (Clearblue, 2022). If you wait until after you miss your period, the same tests are about 97–99% accurate (MedlinePlus, 2020).
That’s because all tests measure a pregnancy hormone called hCG (human chorionic gonadotropin), and these levels rise steadily over the first few weeks after conception (Gnoth, 2014).
How pregnancy tests work
You can test for hCG using a home urine test or getting a blood test. The amount of hCG rises rapidly during early pregnancy, but not right away. The newly fertilized egg has to travel down your fallopian tube and implant into the uterine wall first, which happens about 6–10 days post-ovulation.
Everyone’s implantation window is a little bit different, so hCG levels rise at varying rates. Once this hormone starts flowing, levels double every two days. Sensitive pregnancy tests can detect hCG pretty early and give a positive result (Su, 2015; Gnoth, 2014).
Knowing whether you’re pregnant as soon as possible can be very important. However, if you test too early, there won’t be enough hCG to detect and the test will be negative. The same test taken a few days later could turn positive (Gnoth, 2014).
How to take a pregnancy test
If you’re looking to test 8–9 days after ovulation, you’ll need a kit that says it yields results six days before a missed period. These super sensitive home tests can measure lower levels of hCG.
Can an ovulation test detect pregnancy?
As for the time of day, morning urine works best. Taking the test when you first wake up before drinking water keeps the concentration of hCG higher. To get accurate results, make sure to follow package instructions. Most home pregnancy tests involve the followings steps (FDA, 2019):
- Hold the test stick in your urine stream (or collect urine in a cup) and dip the strip in.
- Check for a control line. This tells you the test is working properly.
- Wait the exact amount of time the product recommends before checking results (usually about five minutes).
It depends on the brand, but most tests produce a colored line if you’re pregnant. Many have symbols, words, or other ways of showing you the results. If you’re using a test that shows a line, even a faint one, there is hCG in your system. If the control line is blank, the test isn’t working and you should take another one.
When is it too early to take a pregnancy test?
Taking a test before the 8 days post-ovulation point (around six days before a missed period) will probably give you a negative result––even if you’re pregnant.
That’s because even though implantation is possible this early, it usually doesn’t happen until around 8–10 days post-ovulation and hCG levels may not be high enough for the test to detect yet (Nepomnaschy, 2008).
It’s called a false negative result when a test comes back negative, even though you’re pregnant. False negatives are fairly common if you take a pregnancy test early, so it’s important to take another later to confirm results (FDA, 2019).
Taking a test too early also increases the risk of a false positive. In these cases, a test may show there’s a pregnancy, then a woman gets her period not long after. There are several things that can cause a positive result followed by a pregnancy loss.
A chemical pregnancy occurs when an egg implants, which boosts hCG levels, but then stops growing. Because hCG levels rose, an early test can show a positive pregnancy result. Chromosomal abnormalities are the most common cause of a chemical pregnancy. Often women wouldn’t have known they were pregnant if they didn’t take an early test (Dugas, 2021).
When to take a pregnancy test
An ectopic pregnancy happens when the egg implants somewhere other than the uterus––usually the fallopian tubes. These are not viable pregnancies. Still, ectopic pregnancies lead to a rise in hCG levels yielding a positive result (Mummert, 2021).
Certain fertility drugs that stimulate the body to ovulate contain forms of hCG. Known as trigger shots, these can lead to false positives. If you’re treating infertility, your healthcare provider can advise you on how medications may affect a pregnancy test (Oyatogun, 2021).
There are different types of hCG, and the ones in dietary supplements can affect test results. It’s best to check the ingredients on the label and let your healthcare provider know what you’re taking if you’re trying to get pregnant. This is also a good practice even if you’re not trying to conceive (Oyatogun, 2021).
Rarely, tumors and certain pituitary conditions produce a form of hCG that could show a false positive (Oyatogun, 2021).
What do the results mean?
If you have what you believe is a false result—whether negative or positive—it’s best to contact your healthcare provider.
If you’re experiencing early signs of pregnancy (such as breast tenderness) or if you’ve had unprotected sex, there is a chance you’re pregnant. You can take a second home test or visit a healthcare provider who can confirm the results with a blood or diagnostic test.
How long does it take to get pregnant after sex?
Best time to take a pregnancy test
Ultimately, the best time to take a pregnancy test comes down to personal preference. If you get a positive pregnancy test result, it could be information you needed sooner rather than later. Keep in mind that false negatives are possible and it’s best to confirm results with a second test.
For the most accurate results, many healthcare professionals recommend taking a home pregnancy test on the first day of your missed period. You can also wait an extra week so hCG levels are high enough to produce a result (FDA, 2019).
In general, don’t assume a negative test will stay negative during the early weeks of potential pregnancy. If you’re actively trying to get pregnant, it’s never too early to think about what a healthy pregnancy requires (like prenatal vitamins for instance). It’s also a good time to talk with your healthcare provider about proper diet and lifestyle habits to ensure a healthy pregnancy.
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Dr. Chimene Richa is a board-certified Ophthalmologist and Senior Medical Writer/Reviewer at Ro.