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When should I take a pregnancy test?
When to take a pregnancy test, how soon a test can detect pregnancy, why false negatives happen and when to test again or call your doctor.
Updated
In short
When should I take a pregnancy test?
Take a home pregnancy test from the first day of your missed period, and for a more reliable result, about a week after it. If you don't know when your period is due, test at least 21 days after unprotected sex. A positive result is almost always right. A negative result can be wrong if you test too early, so test again a few days later.
Written by the Gyne team · Medical review: pending
Key takeaways
- Most home tests work from the first day of your missed period.
- Waiting a week after your missed period gives a more accurate result.
- Testing too early is the most common reason for a false negative.
- Use your first morning urine and follow the instructions exactly, including the timer.
- If two tests are negative and your period still hasn't come, talk to your doctor.
How soon can a pregnancy test detect pregnancy?
Pregnancy tests look for hCG, a hormone your body starts making after a fertilized egg attaches to your uterus. That begins around 6 days after fertilization, and the level roughly doubles every few days.
Most home tests can find it from the first day of a missed period. Some very sensitive tests work a few days earlier, but many pregnant people still get a negative result in the first days after a missed period.
A blood test at your doctor's office can find hCG sooner, about 6 to 8 days after ovulation.
What time of day should I take a pregnancy test?
You can test at any time of day. If you're testing early, your first morning urine is best, because it usually has the most hCG.
Don't drink a lot of fluid before you test. It can dilute your urine so the hormone doesn't show up.
How do I take a home pregnancy test correctly?
Every brand is a little different, so read the leaflet first. In general:
- Check the expiration date on the box.
- Hold the stick in your urine stream, or collect urine in a clean cup and dip the stick, as the instructions say.
- Set a timer for the waiting time, instead of guessing.
- Check that the control line or symbol appears, which shows the test worked.
- Read the result within the time the instructions give.
What does a faint line on a pregnancy test mean?
A faint line usually means the test is positive, as long as it appears within the reading time. Any change in the result window, bold or faint, counts as positive.
A positive result is almost always correct. Call your doctor to confirm the pregnancy and start care.
If you're not sure how you feel about the result, you can talk to a doctor or nurse about your options in confidence. Getting care early helps keep you healthy, whatever you decide.
Why would a pregnancy test be negative if I'm pregnant?
This is called a false negative. It's much more common than a false positive. Common reasons include:
- Testing too early, before your hCG level is high enough.
- Urine that's diluted from drinking a lot of fluid.
- Not following the instructions, or reading the result too soon.
- An expired or faulty test, often with no control line.
- Some medicines, which can affect the result.
- Natural differences, since hCG rises faster in some people than others.
Can a pregnancy test be positive if I'm not pregnant?
It's rare. Some fertility medicines contain hCG and can cause a positive result. If you take fertility medicines, or your result doesn't make sense to you, talk to your doctor.
Hormonal birth control, like the pill, does not change the result of a pregnancy test.
What should I do if my test is negative but my period hasn't come?
Wait a few days, up to a week, and test again. hCG rises each day in early pregnancy, so a later test is more likely to be accurate.
If you get two negative results and your period still hasn't started, call your doctor. Stress, illness, travel and other things can also delay a period.
When to see a doctor
- You've had two negative tests and your period still hasn't come.
- You have a positive test, so you can confirm the pregnancy and start care.
- You have a positive test and any vaginal bleeding.
- You have a positive test with pain low on one side of your belly, or pain at the tip of your shoulder: get care right away.
- You have sudden, severe belly pain, heavy bleeding, or feel very dizzy or faint: call 911 or your local emergency number.
- You take fertility medicines and get a positive result.
How Gyne helps
Gyne keeps your pregnancy tests and ovulation tests in one place, with results over time. When your temperature rises after a positive ovulation test, it moves your period prediction to 12 to 14 days later, so you know when a pregnancy test makes sense.
Trying to conceive and IVFThis guide is general information, not medical advice. Only a doctor can diagnose a condition.