Pregnancy Test Evaporation Lines: What Are They

Evaporation lines are used to detect whether or not a woman is pregnant. These lines are usually placed on the inside of the bottle cap, but they may also be placed on the outside of it. When a woman drinks from a pregnancy test, her urine contains some amount of alcohol which will evaporate into vapor when exposed to air. If there is no alcohol present in her blood, then she cannot be pregnant. Evaporation lines are generally found on the inside of the bottle caps. There are two types of evaporation lines:

The first type consists of a small piece of plastic with a long string attached to it. A tiny hole is cut in one end so that liquid can escape through it. The second type consists of a small strip of paper with a number printed on it. A tiny hole is cut in one side so that liquid can escape through it.

What Is Color Of Evaporation Line On Pregnancy Tests?

There are different colors of evaporation lines. Some have a light blue color while others have a dark blue color. The following table shows the most common colors of evaporation lines:

Color Description Light Blue A light blue line indicates that the test is negative. Dark Blue A dark blue line indicates that the test is positive.

How To Check The Evaporation Line?

If you just finished taking your pregnancy test and the pregnancy test kit has an evaporation line on it, then you should check to see what type of evaporation line that it has. The following steps describe how you should check for an evaporation line:

Look on the inside of the bottle cap. You may see a small piece of plastic or a small strip of paper with a number printed on it. The plastic or paper will be attached to the inside of the bottle cap by a string or thin wire. If you see a small piece of plastic, then the hole should be facing downwards. If you see a small strip of paper, then the hole should be facing upwards.

Turn over the bottle cap and take a look at the top of the strip or piece of plastic. If there is no alcohol in your blood, then you can expect to see some type of line on it. This line may be light blue, dark blue, or some other color. If the test is positive, then the line will be dark blue or black in color. If the test is negative, then the line will be light blue.

What Does It Mean If The Line Turns Out To Be Positive?

If the line that appears is a dark blue or black color, then this indicates that you are pregnant.

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