How does a normal test strip work?
Before you understand and tell why it is better to do the pregnancy test in the morning, consider the principle of these diagnostic tools.
The basis of the pregnancy test is the determination of the level of chorionic gonadotropin (hCG) in a woman's urine. This hormone begins to be produced not from the moment of conception, but after the fertilized egg is implanted into the uterine endometrium. It is from this time that the concentration of hCG increases every day.
Each express test has its own, so-called sensitivity, i.e. this is the lower threshold of hCG concentration, in the presence of which the test starts to work. As a result, it appears on the second strip, indicating the presence of pregnancy. However, this is possible only when the level of hCG is sufficient. The sensitivity of most tests is 25 mM / ml, which corresponds to the 12-14 day of pregnancy.
Why the pregnancy test should be done only in the morning?
The thing is that it is in the morning that the concentration of this hormone (hCG) is maximal. Therefore, the probability that the test will "work" increases. All this is, in fact, the answer to the question, why the pregnancy test is done in the morning.
It is also worth noting that an important factor in the implementation of this study is the gestational age, and not just the time of its conduct. On the package of test strips it is written that they are effective from the first day of delaying menstruation . If you count, it's about 14-16 days after the sexual act. Earlier, it's pointless, even in the morning.