There is hardly any woman in the world who do not want to know about the ensuing pregnancy as early as possible.The first physiological signs of the delicate situation, such as morning sickness, frequent urination, and an increase in breast tenderness, quite subjective and appear after menstruation.
Ultrasound examination of the uterus and the pregnancy will show for a period of at least five weeks.That is why the scientists set out to develop a pregnancy test to delay menstruation.And modern technology has allowed them to successfully resolve this issue.
pregnancy test before the delay for domestic use is based on a qualitative determination of the level of human chorionic gonadotropin (hCG) in the urine of women.HCG - a special hormone that is produced embryo begins immediately after implanted into the uterine wall.
Below are the norm in serum hCG (in mIU / ml) in women:
- no pregnancy (0-5)
- pregnancy in question (5 -25)
- 1-2 weeks (25-156)
- 2-3 weeks (101-4870)
- 3-4 weeks (1110-31500)
- 4-5 weeks (2560-82300)
- 5-6 weeks (23100-151000)
- 6-7 weeks(27300-233000)
- 7-11 weeks (20900-291000)
- 11-16 weeks (6140-103000)
- 16-21 weeks (4720-80100)
- 21-39 weeks (2700-78100)
should be clarified that these rules are approximate and depend on the particular laboratory, which performed the analysis.Moreover, the concentration of hCG in urine is usually slightly lower than in blood.
Most home tests allow "catch" hCG content in urine is greater than 25 mIU / mL.Although sold and more highly sensitive tests with a threshold of 20 mIU / ml and even 10 mIU / ml.
There are several types of home tests for pregnancy.Most of them operate on the same principle.It differs only in the way of diagnosis and the option to display the results.
So, there are jet tests to be a substitute under a stream of urine.There are tests in the form of a tape on which you need to drop a few drops of urine from a special pipette.Typically, such cassettes have a high sensitivity.The most common and cheap tests are in the form of strips.They need to be lowered to a special mark in a small container with urine and hold for 15-30 seconds.
Most often, the presence of the pregnancy can be judged by the appearance of a second strip.Moreover, its brightness is not important.The first strip is a control and shows that the test is not spoiled.Sometimes, instead of the two bars you can see the image of the plus sign.This result also indicates the presence of pregnancy (or minus indicates the lack thereof).
Recently the increasing popularity receive digital tests.The result of the diagnosis carried out with the help of this test, it is very easy to interpret.In the displayed message is not only an electronic display that you will soon become a mother, but also the expected term of the date of conception.
When used pregnancy test
So, go to the most exciting, most women the question: how many days before the delay can confirm pregnancy?Typically, the implantation of the embryo into the uterus occurs 7-10 days after ovulation (DPO), but can be early or late implantation.Below you can see how the likelihood of implantation depends on the DPO:
- 3-5 DPO - 0.68%
- 6 DPO - 1.39%
- 7 DPO - 5.56%
- 8 DPO - 18.06%
- 9 DPO - 36.81%
- 10 DPO - 27.78%
- 11 DPO - 6.94%
- 12 DPO - 2.78%
Immediately after the introduction of a fertilized egg in the uterine wall in the blood (and a little later in the urine) occurs hormone hCG, the level of which doubles approximately every two days.So, if implantation occurred on 7 DPO, the HCG in the blood will be about 2-4 mIU / ml.On 9 DPO hCG levels reach 8 mIU / ml.Only at 11 DAT hCG in blood concentration of 16 mIU / mL, and most early pregnancy test will show a positive result.
And imagine if implantation occurred on the 10th day?That is why doctors do not advise to do a pregnancy test before menstruation and call wait for at least the first day of delay.
When do: morning or evening?
Most manufacturers recommend to diagnose early in the morning, using the first urine.But practice shows that it is enough not to drink plenty of fluids and do not go to the toilet for a few hours.
These recommendations relate to those cases where you spend a pregnancy test before the delay.If the delay has already come, and you suspect that you are pregnant, do not hesitate to carry out the diagnosis, without waiting for the morning.Most likely, the concentration of the hormone hCG in the urine has already crossed the threshold of sensitivity and you will see the long-awaited second strip.