Do you think you may be pregnant? If the rule has been delayed for more than two days, you can take a pregnancy test. In only five minutes you will leave doubts. The absence of menstruation is usually the first symptom, along with nausea and morning sickness, which makes a woman suspect a possible pregnancy. The most simple and quick way to confirm this is the pregnancy test. Today we will learn about the false positive pregnancy test.
What is the pregnancy test?
Before getting to know what a false positive pregnancy test is, we must know what a pregnancy test it? A pregnancy test is a test that detects the presence in the urine of a hormone that the body produces only when the woman is pregnant, the human chorionic gonadotropin hormone (hCG). When the fertilized egg is implanted in the wall of the uterus it behaves like a foreign tissue to the mother’s organism, since 50 percent of the genetic information contained in its cells comes from the father. To prevent a possible rejection, the cells begin to produce the hormone hCG, which slows down the maternal immune system and also stops the menstrual cycle.
When to take the test?
The pregnancy hormone reaches the blood seven to nine days after conception. From that moment, their levels begin to increase rapidly (their amount doubles every two days). The maximum concentration occurs at the end of the third month of pregnancy. From the twelfth week, levels drop. The current tests are able to detect this hormone in the urine at 15 days of conception. In practice, it is recommended to wait up to a couple of days after the menstrual delay to ensure that there is a quantity of hormone high enough to be detected.
How is it used?
The pregnancy tests, which are sold in pharmacies without a prescription, are very simple to use. Just follow the instructions of the prospect and wait for the indicated time to obtain the result. It is important to check the expiration date on the package. If it has been or has been stored for some time in the bathroom, it is best not to use it, since the moisture may have deteriorated. Although almost all tests work with urine at any time of the day, it is recommended to do them with the first morning urine, as it has a higher concentration of hormones.
There are different ways of collecting urine (in a container, with a dropper to apply it later …). The method is always the same: apply a few drops in the part of the device designed for this purpose and wait a few minutes for the substance impregnated in the area to react and detect the presence of the hormone hCG. The ways of expressing the result are different. Some tests show pink or blue lines on the test strip, while others may show a positive (+) or negative (-) sign. Usually, the waiting time for the test to show a result is five minutes, although if it is negative, wait up to 30 minutes because sometimes the positive result takes a time to appear.
Positives, negatives and false positives:
#:- If the result is positive, the woman can be sure that she is pregnant.
#:- If it is negative, there is still a margin of error. In this case, a new test is recommended five or seven days later. If you continue to be negative, but your menstrual period does not recover, you need to talk to the doctor to determine the cause.
#:- The pregnancy tests do not often give false positives, although there are exceptional cases where this can occur, such as when pregnancy does not succeed because it is an anembryonic pregnancy (without embryo). In this case, the hormone was produced by an implanted egg that then stopped its development.
Factors responsible for a false positive pregnancy test:
#:- Take GCH: It is quite obvious, if you are in a fertility treatment (or to lose weight) that include this hormone, will be detected by the test even if you are not pregnant.
#:- Concentrated or contaminated urine: if you take diuretics or other drugs that reduce the amount of fluid in the body can cause a false positive. On the other hand, this can also happen if your urine is contaminated by soap or blood, or you had an abortion recently.
#:- A defective test: the test should be in a cool, dry place at all times. If you carry it in your bag all day you will get an unreliable result. Buy it and use it as soon as possible.
#:- Early response tests: There are many tests that can detect a pregnancy five to six days before the first day of delay. Can these tests even detect a? Chemical pregnancy? (When an egg is fertilized but does not develop and never becomes an embryo), causing days after you get a negative result.
#:- False negatives: If you do not wait long enough (a week late, at least) the results of your pregnancy test may be incorrect because there is not enough GCH to detect. If you cannot wait to have a delay, perform a blood test.
With regard to false positives, we have indicated that the hormone beta-hCG is found in the body only in case of pregnancy. However, there are situations in which the level of this hormone can increase despite not having gestation.
The main cases in which this occurs are:
- Ectopic pregnancy
- Molar pregnancy
Remains of medication for assisted reproduction treatments (in many cases ovulation with hCG hormone is triggered). It is especially important to analyze the cases in which an exaggeratedly high beta-hCG hormone value is obtained since it could be one of these cases, especially a tumour. However, we must bear in mind that in a case of multiple pregnancies, the hormone beta-hCG value is between 30 and 50% higher.