A pregnancy test is used to confirm whether a woman is pregnant by measuring a hormone known as human chorionic gonadotropin (hCG). This hormone can be found in the blood and urine of a pregnant woman starting around a week after conception.
The hCG test can also be used to diagnose an ectopic pregnancy (a condition in which the fertilized egg is implanted outside the uterus) or to assess a woman's condition after a miscarriage.
A blood or urine test is used to determine hCG levels. The blood test is usually performed by a health care professional in a doctor's office or clinic. The urine test can be done on your own at home or at the doctor's office. Home pregnancy tests are available over the counter and are generally quick and easy to use.
To confirm a pregnancy, the test is often done approximately 7 to 10 days after a missed period. For other pregnancy-related issues, your doctor will decide when to conduct the test.
Risks and precautions
The pregnancy test is usually a straightforward and safe procedure.
Before the test
Before you use a home pregnancy test, make sure you check the expiry date on the box and read the instructions that accompany the test. Avoid drinking a lot of fluids before the test because this will dilute the urine and make the test less accurate. Try to do the test first thing in the morning before you drink anything.
If you are taking any prescription or over-the-counter (non-prescription) medications, supplements, or herbal products, make sure you inform your doctor or pharmacist. Ask them whether it is necessary for you to stop taking any of these medications and products before the test. It is also important to tell them if you have allergies to certain medications or have certain medical conditions.