tests for the diagnosis of pregnancy at home divided into several types, each of which has its advantages and disadvantages.Women tend to choose the most sensitive pregnancy test, but to hold it is very important to comply with all the recommendations that are specified in the instructions.Only with this approach to the diagnostic procedure will get the most reliable results.
As tests can determine pregnancy
After pregnancy the placenta starts to produce a hormone called human chorionic gonadotropin (hCG).Last produced in the first hours after fertilization.HCG is released into the blood and excreted in the urine, which is a lesser amount.From the seventh to the eleventh week of pregnancy the concentration of this hormone increases several thousand.Then the hCG decreases gradually.
Rapid tests, which are intended to establish a pregnancy, based on the determination of the presence of hCG in urine.Sometimes during this test can be false-negative or false positive result.So many women want
What are pregnancy tests
Rapid tests come in several forms.They are divided into:
- Test strips (strips);
- test device (tablet tests);
- Ink tests;
- electronic tests.
test strips are very common due to low cost and simple manufacturing techniques.By design, they are a small multi-layered paper strips, which are coated with a special substance.The latter in contact with hCG changes color.
When testing for pregnancy such a strip according to the instruction at a specific time must be placed in a portion of the urine collected in the morning.At this time, the concentration of hCG in the day it will be maximum.
After this test is placed on a horizontal surface until a result.If you see only one control line, which confirms the suitability of the test, the pregnancy has not occurred.The appearance of the two strips (control and diagnostics) shows fertilization occurred.
Use this test is not always convenient for the meeting need to collect urine in any capacity.Paper strips - less accurate way of determining pregnancy of rapid tests.This is due to the fact that the strips require careful compliance with their use.If the test is to immerse the above mentioned signs or hold it in liquid longer than the recommended time, the likelihood of erroneous results increases.
Tablet tests are more convenient to use, but are more expensive.The test cassette is a plastic casing, inside which is a paper strip of absorbent material.On the strip there is a special test area.
Using a pipette, which is attached to the test in one test hole is necessary to put a few drops of urine.In another hole a few minutes after that will result.The disadvantage of this method is the need to collect urine in a separate container before testing.
Inkjet Test - the most effective method for determining the presence or absence of pregnancy.These tests are more convenient to use, urine collection in a separate container is not required.
Inkjet test has a more complex structure.It consists of a fiber core, the test system and the housing.In order to test, you need to substitute a urine stream receiving device side.This test can be used at any time, not only in the morning.
Some women have difficulty in interpreting the results of conventional tests, it is not always appeared the second strip is clear.Sometimes for a positive result can be caused to take on the reagent strip.Electronic Tests not have this drawback, but they are more expensive.On the digital display you can see only one of two results:
- «Plus", which means that pregnancy;
- «Minus" if fertilization has not occurred.
test result will appear after a few minutes and stored in the display during the day.With such a test with a positive result, you can also determine the approximate gestational age.Electronic tests can be both disposable and reusable.
When you need to do a test
The instructions for most of the rapid tests indicated that it was necessary to use morning urine.This is due to the fact that the concentration of hCG in the last above.Ink and electronic tests can be performed at any time of the day.
test for more accurate results, it is recommended to perform the first day of a missed period.But the producers of some tests indicate that they determine pregnancy in the seventh day after conception Conception, ovarian cycle, fertilization and genetics baby .But this is not always time reaches hCG concentrations that can be specified in this way.Therefore, in this period of the test results will be less accurate.
What affects the accuracy of the result
important characteristic tests - sensitivity.It is measured in international units.The lower the figure, the more reliable test, particularly if it is done before the expected start of menstruation.Be sure to pay attention to the shelf life of rapid tests.
before the test should avoid taking diuretics, and large amounts of fluid.The test can show a positive result in the absence of pregnancy in the following cases:
- If a woman takes medications that contain in their composition of hCG;
- When cancer;
- small time period after an abortion.
Sometimes if pregnancy test may show a negative result.This is possible if:
- Tested before any specified date;
- Before the test, the woman drank plenty of fluids and taking diuretics;
- There pathology of the cardiovascular system and kidneys, when the selection discharge in women when there is cause for concern hCG from the body difficult.
No matter which of the tests a woman chooses to obtain reliable results, you must carefully comply with all conditions specified in the instructions.But the most accurate information about the presence or absence of pregnancy can only give a blood test for hCG blood test for HCG (human chorionic gonadotropin) pregnancy test and examined by a doctor.