How to use a home pregnancy test

From how soon you can take one to what to do if it's positive, we have the answers to all your pregnancy test questions.
pregnancy test

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The anticipation is killing you. Are you pregnant—here are 15 signs you might be? You go to the store and survey the sea of options and brands. Which is best? How do they work? Is there more to it then just peeing on a stick? And is it OK to buy the test after work and run home and do it right away? We’ve got your questions answered.

How do home pregnancy tests work?
Home pregnancy tests measure the amount of hCG in your urine. HCG stands for human chorionic gonadotropin, the hormone made by cells that help form the placenta. Say you have a normal 28-day cycle, you ovulate on day 14 and the egg is fertilized a day or two later. The embryo grows for several days, then implants in the uterus and the placenta forms. At that point, hCG starts to get into the bloodstream and filters through the kidneys. That’s when it can be picked up in urine (in this example, around day 25 or 26).

How do I take it?
Each pregnancy test has its own specifics—so be sure to read the instructions carefully. When you are testing, always check the control panel to confirm the test actually worked. “Some people do a pregnancy test, wait a couple of minutes, don’t see a positive and throw it in the garbage when they should have waited longer,” says Dan Nayot, a fertility specialist at the Toronto Centre for Advanced Reproductive Technology.

What time of day should I test?
Early in your pregnancy—either a little before or when your period is due—use the urine from your first pee of the day. “During sleep you aren’t drinking, so your urine is more concentrated and you pick up the hCG more readily,” says Nayot. But by the time you’ve missed your period, the levels of hCG in your urine are quite high, and you can test anytime of the day.

How soon is too soon to test?
A home test can detect a pregnancy before you’ve missed your period (these are the earliest signs of pregnancy), but if you wait until your period is due you’ll be more certain of an accurate result. If you have an irregular period (that is, you get your period every four to six weeks or sporadically) Nayot suggests doing the test one week past when you think should be getting your period.

Can the result be wrong?
False negatives are more common than false positives, and happen when you test too early, or if you’ve done the test wrong. If you get a negative, wait a few days and, if you still haven’t gotten your period, test again.

A false positive means the test has detected hCG, but you aren’t pregnant. “This can happen if you are going through fertility treatment and you get hCG as part of the protocol,” explains Nayot. You can also get a positive result with an early miscarriage or biochemical pregnancy: the test still picks up hCG in your urine, but the pregnancy is no longer viable.

I got a positive result—now what?
If you’ve just missed your period and got a positive pregnancy test result, congratulations! Make an appointment with your doctor who will arrange an ultrasound to take place when you’re around six to seven weeks pregnant. She may also do a blood test to check your hCG levels. (You can estimate your due date using an online calculator if you know the date your last period started. Keep in mind due dates are calculated based on when your ovulation cycle started, not when the egg is fertilized.) This ultrasound will check if the pregnancy is inside the uterus—rather than ectopic—how many pregnancies (you could be carrying twins!), and if the pregnancy is viable. It will also confirm how far along you are.

“Once you have that positive pregnancy test, it should be a sign to take care of yourself,” says Nayot. “Continue to take your prenatal vitamins, avoid alcohol and eat well.”

Brands on the market—What sets them apart
All home pregnancy tests use the same technology, says Nayot, but some make the results more clear, by, for example, showing the word “Pregnant” rather than relying on a line, or showing you how far along you are. Here’s what’s available:

Clearblue
1. Clearblue Advanced with Weeks Estimator will show—if the test is positive— the word “Pregnant” on the display, along with an estimate of the number of weeks since ovulation, which it does by measuring the amount of hCG in your urine.

2. The Double-Check and Date kit has two tests, one to see if you’re pregnant, and another that will confirm in, and tell you how far along you are.

3. Clearblue Plus is more ergonomically friendly, with a wider tip making it easier to catch the urine stream.

Clearblue claims 99 percent accuracy on all their tests if you use them from the day of your missed period, but states you can test four days prior to your period.

First Response
1. First Response claims its Early Result Pregnancy Test can detect “scant” traces of hCG, which makes you able to test six days before your missed period. There is a disclaimer: because hCG levels are low early in pregnancy, First Response says the test detects pregnancy in 76 percent of pregnant women five days prior to the expected period, with that number rising to 99 percent accuracy three days before the period.

2. The Rapid Results pregnancy test will do the test for you in one minute, but you have to test after the day your period was due.

3. The Digital Pregnancy Test also promises you a result six days before your period, and gives you a “yes or no” answer in the display window.

All First Response tests offer a “wide tip” to make it easier to pee on, and a comfortable handle to hold.

Other Brands
The Life Brand sold at Shoppers Drug Mart, the Equate brand sold at Walmart, along with various dollar store pregnancy tests that are approved by Health Canada claim similar accuracy rates and testing times. Keep in mind, however, that dollar store tests may not be held up to the same batch control testing that the more expensive tests are, and, as a result, may not be as accurate.

    Read more:
    Pregnancy by week: Follow along as your baby grows
    How I knew I was pregnant
    5 reasons you’re not getting pregnant

     

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