Researchers have developed a "placenta-on-a-chip" to study the inner workings of the human placenta and its role in pregnancy.

The device was designed to imitate, on a micro-level, the structure and function of the placenta and model the transfer of nutrients from mother to foetus.

"We believe that this technology may be used to address questions that are difficult to answer with current placenta model systems and help enable research on pregnancy and its complications," said one of the study authors Roberto Romero from National Institute of Child Health and Human Development, National Institute of Health, US.

The placenta is a temporary organ that develops in pregnancy and is the major interface between mother and foetus, which serves as a "crossing guard" for substances travelling between mother and foetus.

The placenta helps nutrients and oxygen move to the foetus and helps waste products move away while at the same time, it tries to stop harmful environmental exposures, like bacteria, viruses and certain medications, from reaching the foetus.

When the placenta does not function correctly, the health of both mother and baby suffers.

Researchers are trying to learn how the placenta manages all this traffic, transporting some substances and blocking others.

However, studying the placenta in humans is challenging: it is time-consuming, subject to a great deal of variability and potentially risky for the foetus.

The researchers created the placenta-on-a-chip technology to address these challenges.

"The chip may allow us to do experiments more efficiently and at a lower cost than animal studies," Romero said.

"With further improvements, we hope this technology may lead to better understanding of normal placental processes and placental disorders."

The study was published online in the Journal of Maternal-Foetal & Neonatal Medicine.