Pregnancy: blood test Saviour of miscarriage and pre-eclampsia
Attention – The study still needs to be deepened, but it opens the way for the identification of severe gestational problems still in the first trimester.
Good news: Scientists at the Laboratory for Reproductive Medicine and Embryology have developed a blood test that can detect early problems in pregnancy. They analyzed the blood cells of pregnant women during the first trimester and from there they were able to predict the risks of developing preeclampsia, as well as having preterm birth, low birth weight, and miscarriage.
Research has assumed that these major obstetric problems have a common biological origin. So, from white blood cell analysis, scientists have identified 30 molecules of RNA related to gene expression that can determine the risk of these problems developing. In other words, by analyzing blood samples from 160 women who had and who had no problems during pregnancy, the specialists identified some changes in the RNA molecules, which may serve as indicators of future complications.
The chances of developing pre-eclampsia could be predicted with 90% accuracy. On the other hand, the risk of premature birth before 34 weeks could be calculated with acuity of 89% and birth between 34 and 38 weeks, with an accuracy of 92%. Once the symptoms of these problems begin to manifest only between the second and third trimesters of pregnancy, identifying the risks before can be a good opportunity for prevention.
The results were released at the annual meeting of the American Association of Reproductive Medicine. But it’s too early to celebrate. “It is a small, preliminary study that indicates some paths to science, but it is still not possible to think of a commercially available test in the short term,” explains obstetrician and gynecologist Javier Miguelez, responsible for Hospital Fetal Medicine. Maternity São Luiz Itaim (SP). This means that this test still needs to be done with thousands of patients before their use is considered on a larger scale. In addition, a number of studies need to be done to enable it at an affordable cost.
Fortunately, today, there is already a commercially available test that can predict complications early in pregnancy: the first trimester biochemical screening. It evaluates three hormones in the mother’s blood (PAPP-A – plasma protein-a-gestation-, free Beta HCG and PLGL – placental growth factor), combined with maternal blood pressure, blood flow to the uterine arteries (assessed by ultrasonography) and maternal risk factors, indicated through a questionnaire that the pregnant woman responds. Combining all these results, it is possible to trace the risks of developing a series of complications in pregnancy, mainly pre-eclampsia. “Around 90% of the cases of development of this disease before the 34th week can be detected with this test,” Miguelez adds. The biochemical screening of the first trimester is not available in the public health system, and in the private network it costs around 1400 reais.
It is worth remembering that the earlier a large risk of developing pre-eclampsia is identified, for example, the more likely the pregnant woman has to reverse this condition. “With the administration of aspirin from the beginning of pregnancy, it is possible to reduce from 60-80% of these cases,” explains the obstetrician. In contrast, although it is possible to identify the chances of spontaneous abortion, doctors do not, because in these cases there is nothing that the pregnant woman can do to prevent it.