When To Take Pregnancy Test at Home

Published May 31st, 2022 by Bridget Reed
Fact Checked by
Camille Freking
Medically Reviewed:
Chris Riley

Believe it or not, there is a right and wrong time to take a pregnancy test at home. 

If you take it too early, you can get a “false negative” result and be very surprised when the baby bump starts to develop.

If you take it too late, you can miss out on important prenatal care, which helps ensure a safe and healthy pregnancy. 

In this guide from USA Rx, we’ll go over how pregnancy tests work, the best time to take a pregnancy test, and three signs that you should take one ASAP. 

How Does a Home Pregnancy Test Work?

Home pregnancy tests work by checking for levels of human chorionic gonadotropin (hCG) in your body.

This is a hormone that your body releases in high amounts after conception.

While everyone — pregnant or not — has some level of circulating hCG, more of this hormone is needed to help your baby grow, which is why it rapidly increases from conception onward. 

A home pregnancy test checks for higher-than-normal levels of hCG in the urine.

A test may ask you to collect your urine in a cup and dip the test inside the liquid. Another option is to pee directly on the test. 

when to take pregnancy test

If your hCG levels are higher than normal, you’ll receive a positive pregnancy test result.

Depending on what type of test you use, you may see a confirmatory vertical line appear on the display, a plus or a minus, or the words “pregnant” or “not pregnant.” 

HCG starts to increase after the fertilized egg implants itself into the uterus.

It should take about 10 days after conception for this to happen, which means that taking a pregnancy test earlier than that may not give you the most accurate results.

It’s best to wait until your first missed period for the most accurate reading. 

Signs That You Should Take a Pregnancy Test 

Unless you’re trying for a baby and are regularly taking pregnancy tests, there are some signs to keep an eye out for that may indicate you’re pregnant. 

Here are three reasons it may be time to take a pregnancy test: 

  1. Your contraceptives failed: Studies show that condoms break in as many as 7% of all cases. Birth control pills aren’t as effective if pills are missed. If your contraceptives fail during the ovulation portion of your menstrual cycle, it can result in a pregnancy. Wait about two weeks after the event to take a pregnancy test for the most accurate results. 
  2. You missed your period: This is a very reliable sign of pregnancy. If you track your cycle and notice that your period is several days late, you should take a pregnancy test. But keep in mind that factors like travel, stress, and intense exercise can also make you miss your period, so don’t assume that you’re pregnant until a positive result confirms it. 
  3. You have morning sickness: Hormonal changes during pregnancy can lead to early pregnancy symptoms, like nausea and vomiting in the morning. If you experience these symptoms and can’t find another explanation for them, then a pregnancy test can quickly help you confirm (or discount) another explanation. 

When Should You Take a Pregnancy Test?

You should wait to take a pregnancy test until after your missed period for the most accurate results. 

A period can come late for many reasons, and if you’re not experiencing early signs of pregnancy like morning sickness or nausea, waiting to test can also save you money (and maybe even a bit of anticipation anxiety). 

If you haven’t been actively tracking when your period comes and goes, you can estimate when your next period should come based on average cycle length.

While you do need to try and figure out when the first day of your last period was, that’s the hardest part — on average, a cycle lasts about 28 days, meaning you’ll have a period about every 28 days or so. 

To make it simple: If it’s been more than four weeks since your last period and your next period is nowhere in sight, it may be a sign to take a pregnancy test.

If you’re trying to get pregnant and can’t wait until your missed period for results, you should wait to test at least 10 days until after you’ve had sex.

This is about how long it takes your body to develop detectable levels of hCG after the fertilized egg implants itself in the uterus. 

If you take a pregnancy test too early in your cycle, then your test may not detect rising hormone levels in your urine.

As a result, you may get a test result that says you’re not pregnant (when you really are). 

When Should You Use a Pregnancy Calculator? 

A pregnancy calculator tells you an estimated date of when your due date could be.

It’s based on either the last date of your last period or your conception date. Your baby should be born about nine months after conception. 

You can use a pregnancy calculator as soon as you confirm you’re pregnant. However, keep in mind that a pregnancy calculator is just an estimate of your due date.

Nothing beats a visit to your obstetrics and gynceology doctor for medical advice and your most accurate due date. 

How Do You Take a Pregnancy Test?

To reduce the risk of getting an inaccurate result on your pregnancy test, here are some best practices to follow when taking a pregnancy test

  • Read the instructions that come with your specific home pregnancy kit: Each pregnancy test uses a different method for collecting your urine and displaying results. If you don’t perform the urine test correctly, you can get the wrong result. 
  • Take the test after your first missed period: As mentioned above, it typically takes at least 10 days for hCG levels to build up in your urine. Give your body enough time to build up this pregnancy hormone before taking a pregnancy test. 
  • Avoid drinking too many fluids in the two hours or so before testing: Excessive fluids can dilute hCG levels in your urine and give you the wrong results. Try to avoid drinking too many fluids before taking your pregnancy test. 
  • Take the test in the morning: Your morning urine will be most concentrated in hCG. This will give you the most accurate results, especially earlier in the pregnancy. 

In Summary

You should take a pregnancy test after your first missed period for the most accurate pregnancy test results.

Preferably, you should wait about a week after the first day of your expected period. 

Once you know that you’re pregnant, you can use a pregnancy due date calculator to estimate the baby’s arrival, but you should make sure to schedule a doctor’s visit as soon as you find out about your pregnancy.

It’s standard to take a blood test for confirmation and to determine your gestational age. 

From there, prenatal care can begin, milestone appointments can be planned, and you can work with your provider to help make sure you’re equipped with the guidance you need for a smooth pregnancy!

References and Sources: 

Human Chorionic Gonadotropin | NCBI Bookshelf 

How Often Do Condoms Break or Slip Off in Use? | NCBI 

False-positive Urine Pregnancy Test Due to Leukocyte Interference | PMC