Research identifies possible cause of premature births

Researchers at the University of Nevada, in the United States, have found a new clue to understanding preterm labor. They have identified a protein that acts to relax the uterus and hope that the discovery will pave the way for treatments capable of ensuring the continuity of pregnancy and delivery at the right time.

“We are now working on a combined three-substance approach to preventing preterm birth,” says researcher Iain Buxton, one of the authors of the paper published this week in The Journal of Physiology. The three-drug regimen will be tested on animals and, according to the results, could be used by pregnant women in the future.

In the study, Buxton and colleagues Scott Barnett and Hazik Asif used tissue samples to explore the dynamics of the uterus and present for the first time the action of the Piezo1 protein on the myometrium, the layer responsible for contractions.

According to the researchers, Piezo1 allows the passage of calcium atoms that activate the production of nitric oxide, which is important for keeping the organ in a state of relaxation. They also found that, in cases of preterm labor, this channel appears unregulated.

“Studies like this represent a great advance”, says Denise Leão Suguitani, director of the Brazilian Association of Parents, Relatives, Friends and Caregivers of Premature Babies – NGO Prematuridade.com. “It opens up a range of possibilities to work on preventing premature birth not only from hormonal aspects.”

Each year, about 13 million babies are born at less than 37 weeks’ gestation. In Brazil alone, there are more than 300,000 cases every year, according to data from the Information System on Live Births of the Ministry of Health. In 2020, the last year for which information is available, 308,702 children were born earlier than expected, equivalent to 11.3% of the 2,730,145 births, a number that places the country in tenth position in the world ranking of prematurity.

In the article, the researchers highlight that prematurity is the main cause of death in children under 5 years of age and point out that those who survive often remain with sequelae. Still, little is known about the mechanism that causes preterm labor and there are no medications capable of preventing contractions before the time.

“The research idea arose from the peculiar nature of the human uterus, which is different in its regulation from the animals often used to study pregnancy”, says Buxton. Intrigued by the absence of nervous regulation of the uterus during pregnancy, they focused their attention on other possibilities for controlling the functioning of the organ.

Along the way, they discovered that the process described by the 1998 Nobel Prize winners in medicine, which showed how nitric oxide transmits signals throughout the body, did not work in the musculature of the uterus in the same way as in the blood vessels. This phase of the study involved the Brazilian Veronica Arinze, who works as a nurse in Nevada, and served as the basis for the investigation of Piezo1.

“Science’s time is usually long and we cannot sit idly by, a lot can be done while studies are being carried out. Sex education works for adolescents; investment in family planning and in health teams that work with prenatal care and childbirth, both in primary care and in hospitals; and major campaigns to raise awareness of the population about the causes and consequences of prematurity, the importance of prenatal care and the demystification of natural childbirth are examples of what can be done to reduce cases of childbirth premature babies in Brazil”, says Suguitani.

She recalls that Covid-19 increases the risk of prematurity and emphasizes that more attention needs to be paid to the topic. “There is an effort from science, but given the severity of the prematurity scenario in the country, we need to do, publicize and invest much more.”