When to take a pregnancy test for an accurate result
The short answer
Take a home pregnancy test from the first day of your missed period. If you don’t know when your period is due, test at least 21 days after the last time you had unprotected sex. Any time of day is fine. If the result is negative but your period still doesn’t come, test again a few days later.
How a pregnancy test works
Every pregnancy test looks for a hormone called hCG (human chorionic gonadotrophin). Your body starts making it around 6 days after fertilisation, and the amount rises over the following days. A test taken too early may find too little hCG to show a result, even if you are pregnant.
That is why the first day of a missed period is the usual advice: by then most pregnancies have enough hCG for a standard test.
Can I test before my period is late?
Some very sensitive tests say they work a few days before a missed period. They can, but an early negative result is more likely to be wrong. If you test early and get a negative, test again once your period is late.
Working out when your period is due
Your period is due on the first day of your last period plus your usual cycle length. For example, if your last period started on 1 March and your cycles are about 30 days, your next period is due around 31 March. The free next period calculator works this out for you, and the Nepali (BS) period calculator does it with Bikram Sambat dates.
If your cycles are irregular, use the 21-days-after-sex rule instead.
Reading the result
- Positive: a positive home test is almost always correct, even if the line is faint. Fertility medicines that contain hCG can give a positive result when you are not pregnant, so check with your doctor if you take them.
- Negative: less reliable. It can be wrong if you tested too early or did not follow the instructions exactly.
Always follow the instructions in the box, as each brand is slightly different. Most show the result within a few minutes.
Does birth control affect the test?
No. The hormones in the pill and other hormonal birth control do not stop a pregnancy test from working. No method of birth control is 100% effective, so take a test if you think you might be pregnant.
Negative, but no period?
Wait a few days and test again. If the second test is negative and your period still hasn’t come, see a doctor or health worker. A late period has many causes besides pregnancy, such as stress, weight change, illness or PCOS (now also called PMOS). Read why is my period late?
Get help straight away if
You might be pregnant and have bleeding with pain in your belly or on one side, pain in the tip of your shoulder, or feel faint or dizzy. These need urgent medical care. Call your local emergency number (in Nepal, 102 for an ambulance).
If the test is positive
Contact a doctor, midwife or health worker to start antenatal care, ideally in the first 12 weeks. If you are not sure you want to continue the pregnancy, you can talk to a health worker in confidence about your options.
To estimate your due date and how many weeks pregnant you are, use the due date calculator or the Nepali (BS) due date calculator. For the early signs, see am I pregnant or is my period coming?
Sources
Try the Next period calculator, or see Cycella in Nepal. Cycella is a free, private Android period tracker, now on Google Play.
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