The most affordable way to early diagnosis of pregnancy, when the delay is only a few days, this urinary test. To understand how a pregnancy test, it is necessary to know the length of the menstrual cycle The menstrual cycle - that occurs in different phases?   women and representation of major changes in the female body during pregnancy. Its parameters are different tests of varying sensitivity, so research before the woman should carefully review the instructions supplied.

The principles on which the analysis is built

The basic principle of the urinary test that makes it possible to establish the existence of pregnancy, this reaction of the urine of women with a special reagent. This reagent is applied to a diagnostic test strip, wherein in case of pregnancy the color change strips (two strips staining).

From the moment of implantation, when the fertilized egg has taken root in the endometrium starts to develop a unique hCG pregnancy hormone (human chorionic gonadotropin). His producing cells growing chorionic villi (cells called syncytiotrophoblast). Hormone itself is structurally composed of a glycoprotein subunit. The diagnostic value for detection of pregnancy has its b-cubedinitsa. Based on the reaction of the subunit with the reagent can diagnose pregnancy. This is possible thanks to the fact that the blood subunit of hCG may be detected already on the ninth day after conception Conception - as the emerging life . In the analysis of the blood to determine the concentration of the hormone HCG can even before the missed period, and in the urine is detected later.

The most important thing - to choose the right test for the study taking into account the sensitivity of the tests. If the test is performed on the date when the sensitivity is not the same as the concentration of hCG in the body, the result may be uninformative. In such a situation may be a negative result in the presence of ongoing pregnancy.

The value of the sensitivity of the urinary test

Given the difference in the sensitivity of urinary test to get the most reliable results should have an idea of ​​which test is best to choose for diagnostic purposes. The pregnancy hormone hCG begins to be produced since the introduction of the egg into the uterus during the ensuing days after the implantation of the egg. In urine the hormone becomes informative if at least one day of missed period. The sensitivity of the test is determined from ten to twenty-five or more mIU / ml.

It is important to know the following provisions on the test systems:

• the smaller the gestational age, the more informative test will be the least sensitive. If a woman's missed period is only a few days (diagnosis from the first day of the expected, but not the ensuing period), then it is better to buy the test with a sensitivity of 10 mIU / mL. This would correspond to an average of fifteen days the ensuing ovulation and fertilization;
• with an increase in the duration of the delay must be purchased for the more sensitive diagnostic tests;

It is imperative that strict adherence to the instructions that came with the test system. It is important to do the test in the morning, because in this period the concentration of the pregnancy hormone is high. In no case overdo the time analysis. It is a mistake to think that in order to obtain reliable results should keep the test system in the analysis of the urine for more than ten minutes to come color development of the strip. The best time to test is between five and ten minutes. Unless this condition is satisfied, then this can lead to distortion of the results due to the fact that the evaporation of the dye may occur, and will "line evaporation." This can be interpreted as a positive result that may not be accurate.

Marina Solovyov

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