Microplastics are ever-present in daily life — in water, food and soil. Now, they’re a fact in utero, too, a new medical report revealed.

In a study of expectant mothers, microplastics were recently detected throughout the placenta — which connects mom to baby — in four healthy, pregnant women. In tests analyzing just 4% of each individual’s placenta, at least a dozen plastic particles were found.

“It is like having a cyborg baby: no longer composed only of human cells, but a mixture of biological and inorganic entities,” said Antonio Ragusa, director of obstetrics and gynecology at the San Giovanni Calibita Fatebenefratelli hospital in Rome.

“The mothers were shocked,” he told Italian newspaper La Repubblica, as first reported in English by the Daily Mail.

Scientists aren’t sure how microplastic — less than 5 millimeters wide by definition — affects human health. On observation, they appear to pass through the digestive tract with the other stuff we eat. What happens in the meantime remains largely a mystery.

The stakes are significantly higher for pregnant women, which is why it’s so critical to understand what plastic does inside the human body — at any stage of life. That’s why scientists are calling this new report a “matter of great concern.”

Ragusa and his colleagues, whose findings were published in the journal Environment International, believe this may be just a snapshot of the total plastic volume in the average placenta.

The microplastics found were around 10 microns in size — that’s one one-hundredth of a millimeter — small enough to circulate the bloodstream among cells that are just 2 or 3 microns smaller.

Doctors fear microplastics aren’t stopping at the placenta and could be playing a role in how a baby develops.

“Due to the crucial role of placenta in supporting the fetus’ development and in acting as an interface with the external environment, the presence of potentially harmful plastic particles is a matter of great concern,” researchers wrote in their report.

The composition of plastics vary, some include chemicals that are known to disrupt hormone regulation or chemicals linked to certain cancers. Meanwhile, scientists are discovering plastic in every corner of life, newborns notwithstanding. Earlier this year, researchers found that polypropylene bottles for baby formula were emitting millions of plastic particles into the nutritional milk with each day of use.

Study authors urged the research community to continue their investigation.

“Further studies need to be performed to assess if the presence of microplastics may trigger immune responses or may lead to the release of toxic contaminants, resulting in harm,” they wrote.