When should you take a pregnancy test?
The most reliable time to take a pregnancy test is from the first day your period is late. Most home tests detect pregnancy from then. Sensitive early tests may work a few days before, but can miss a pregnancy. If you don't know when your period is due, test at least 21 days after unprotected sex. Morning urine works best early on.
Why timing matters
Pregnancy tests detect hCG, a hormone your body only starts making once a fertilized egg implants in the uterus, usually about 6 to 10 days after fertilization. hCG then roughly doubles every couple of days. Test too early and there may not be enough to show up, even if you're pregnant.
| When you test | How reliable |
|---|---|
| Before implantation (about a week after sex) | Can't detect pregnancy yet |
| 4 to 5 days before your period is due | Early tests sometimes positive, often negative even if pregnant |
| 1 to 2 days before your period is due | Better, but false negatives still happen |
| The day your period is late | Most tests are reliable from here |
| A week after your missed period | Very reliable if used correctly |
Our pregnancy test calculator works out your best test date from your last period or the date you had sex.
How to get an accurate result
- Use your first pee of the morning if you're testing early; it's the most concentrated.
- Don't drink lots of water just before testing.
- Follow the instructions exactly and read the result in the time window given, not hours later.
- Any second line, even faint, usually means pregnant. Test again in 2 to 3 days to confirm.
- If it's negative and your period still hasn't come, test again in a few days.
With irregular cycles, wait at least 21 days after the unprotected sex before testing. That gives hCG time to rise whatever your cycle is doing.
PMS or pregnant?
The two weeks before a period are hard to read. Sore breasts, tiredness, cramps, bloating and mood changes can come from PMS or early pregnancy, because progesterone drives both. The only way to know is a test. See PMS vs pregnancy symptoms and period cramps vs pregnancy cramps. If your period is late and the test is negative, see late period, negative test.
See a doctor if you get a positive test, if tests keep coming back negative but you've missed 3 periods, or urgently if you could be pregnant and have one-sided pelvic pain, shoulder-tip pain, heavy bleeding or fainting.
Frequently asked questions
Can I take a pregnancy test 7 days after sex?
It's too early for most people. Implantation may not have happened yet. Wait until your period is late, or 21 days after sex.
Can a pregnancy test be wrong?
False negatives are common when testing early. False positives are rare but possible, for example after a very early pregnancy loss or with some fertility medicines.
What time of day is best for a pregnancy test?
Morning, especially if testing early. Later in pregnancy any time of day works.
How long after implantation bleeding should I test?
Wait at least 3 to 4 days after any spotting, and ideally until your period is late. See what implantation bleeding looks like.
Sources
- NHS: Doing a pregnancy test
- Cleveland Clinic: Pregnancy tests
- NHS: Signs and symptoms that might mean you're pregnant
This page is for information only and isn鈥檛 medical advice. If something worries you, please talk to a doctor.
Keep reading
When to take a pregnancy test: find your most accurate dayWhen to take a pregnancy test: enter your last period and cycle length to see the earliest testing day and the day a result is most reliable.PMS or pregnancy? How to tell the differencePMS vs pregnancy symptoms look almost the same: sore breasts, cramps, tiredness, mood swings. The few clues that differ, and when a test is reliable.Late period but a negative pregnancy test?Late period but a negative pregnancy test? You may have tested early or ovulated late. Other common causes, when to retest, and when to see a doctor.
What does implantation bleeding look like?What does implantation bleeding look like? Light pink or brown spotting, no clots, lasting hours to 2 days. How it differs from a period and when to test.
Late period: the common reasons and what to do nextLate period and not sure why? Pregnancy, stress, illness, weight, exercise, PCOS, thyroid and perimenopause explained, plus a clear plan for what to do.