According to a study from Stanford University School of Medicine, for the first time a way has been found to predict when the time of delivery is approaching in a pregnant woman by analyzing immunological and other biological signals in a blood sample. .
This is quite a milestone because current estimates were imprecise until now , and anything in a five-week window, from three weeks before to two weeks after the due date, is considered normal time.
Blood markers
The shift to maternal biology before delivery is characterized by changes in steroid hormone levels, factors that control blood vessel growth and blood clotting, and immune regulatory signals.

In the study, each blood sample was tested for 7,142 single-celled immune, protein and metabolic characteristics. The data was compared to the number of days before delivery that each blood sample was taken, ensuring that the analysis is sensitive to signals of impending delivery, as opposed to signals primarily related to the length of pregnancy or pregnancy. baby growth. The researchers identified, through mathematical models, which characteristics in the blood best predicted the onset of labor .
As they progressed into the prepartum phase, the woman’s blood showed surges in steroid hormones such as progesterone and cortisol, confirming previous findings on the biology of late pregnancy. The blood also showed decreasing levels of factors that help blood vessel formation, probably a first step toward weakening the connection between the placenta and the uterus, as well as increasing levels of factors necessary for blood clotting. , which help prevent blood loss after delivery. Some placental proteins also increased .
The researchers hope their findings will produce a test in the next two to three years that doctors can use to predict the onset of labor in healthy pregnancies. The method reduces the expected turnaround time to a two-week window , and the researchers hope it will become even more accurate as the technique is refined.
Currently, doctors estimate a woman’s due date by counting 40 weeks from the first day of her last menstrual period and taking into account ultrasound data on the size of the baby.