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How do you accurately guess the date of labor?
Last reviewed: 02.07.2025

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Experts have proposed a new diagnostic method that helps determine the date of birth with maximum accuracy.
In order to calculate when a pregnant woman should give birth to a child, doctors use information collected during an ultrasound examination, and also rely on the date of the last menstruation. It is this date that gives an approximate idea of when conception could have occurred. Ultrasound allows you to compare the period with the degree of intrauterine development of the future baby.
However, despite the logical calculations used, the error still remains considerable: the error can be up to 5 weeks. Many specialists additionally use other indicators, such as the length of the cervix. However, this method does not always "work".
Representatives of Stanford University took on the task of solving this problem using blood analysis. They conducted a study involving several dozen pregnant women who were in the second trimester of pregnancy. During the experiment, scientists took blood from women several times for analysis – the levels of various biological markers, proteins, and substances that appeared as a result of metabolic processes were assessed. The obtained indicators were then compared with those that were detected on the day when the participants in the study began to give birth.
As a result of the work, the scientists were able to identify 45 molecular components that could indicate the approach of labor. The researchers then rechecked their assumptions by studying the tests of ten more expectant mothers. Indeed, the due date was predicted approximately three weeks in advance.
Perhaps the only drawback of this method is that the tests should be carried out repeatedly, at least several times during the entire period of gestation. After all, specialists should determine the dynamics of the isolated molecules. For example, the level of the placental hormone 17-hydroxyprogesterone is indicative: its sharp increase indicates that it is time for a woman to prepare for childbirth. A similar indicator is the increased concentration of the immune protein IL-1R4 - the so-called type IV receptor to interleukin-1. An increase in this value indicates that labor will begin in about a month.
Currently, scientists are trying to improve and refine the list of diagnostic indicators, determine the frequency and periodicity of blood sampling for analysis. Specialists point out an important point: in this way, it is possible to determine not only the time of normal birth, but also the date of premature labor. The ability to prepare in advance for the premature birth of a child is another chance for such a baby to survive.
The materials are presented on the page TheScientist