Many of them will require the user to urinate on a stick or into a cup, a few les popular will perform the test with a drop of blood instead. Some uses a digital reading, while others will show a plus sign or double line in the event that it detects enough pregnancy hormones to determine a pregnancy.

Some pregnancy tests are "early" pregnancy tests. That means that they are designed to detect a small enough amount of the pregnancy hormone to determine if a woman is pregnant as early as the first day of a missed period, or even a day or two before the period is due. The fine print on the boxes will tell you that 65% of pregnant women had a positive result when tested two days before the period was due, and the percentage increased with each passing day. These are usually accurate, but the most accurate results are achieved after the period was expected. A woman will not get a false positive in most cases, but a negative result will occur if there is not enough pregnancy hormone detectable yet, even if the pregnancy is positive.

For a woman, the highest level of pregnancy hormone is found in first-morning urine. That is the best time to use a pregnancy test strip. Most of the kind a woman urinates on need to be saturated with urine in order to work properly. Therefore, be sure to hold the stick in the urine stream for 3 good seconds or more.

It takes about 5 minutes for the urine to travel down the strip and the results to be indicated. The stick must be read within 10 minutes, or it may indicate a positive result after 10 minutes, even if the result is actually negative. Positive results that show up within the first 10 minutes may be very faint. This would happen if it is early, and the pregnancy hormone is just barely detected. Even a faint result is a positive result. The woman can confirm the positive by taking another test a day or two later to see a darker line appear.

Pregnancy tests are very accurate when used correctly. But, remember, they must be used at the right time of the month. Too early, and a false negative result will occur, due to the need for the pregnancy hormone to be present in a high enough quantity for the stick to measure. If the menstrual period is two weeks late, and the pregnancy test is still negative, an appointment with the doctor might be indicated.

Finally, if you are pregnant, you should make an appointment doctor. Early monitoring of the baby will allow the doctor to monitor the growth of the baby closely and advise you accordingly.