Researchers from Stanford University in the US have collaborated with international scientists to develop new blood tests for pregnant women that can predict premature birth and determine the gestational age of a foetus.
The new approach is less expensive than ultrasound and is expected to help minimise problems associated with premature birth, which is known to impact 15 million infants per year globally.
Designed to measure maternal, placental and foetal gene activity, the new tests look for cell-free RNA fragments in a mother’s blood.
The team collected blood samples from pregnant women in order to determine genes that gave reliable signals about the risk of premature birth and gestational age.
They used samples from 38 US women at risk of premature delivery, as they had already experienced early contractions or had given birth to a preterm baby previously.
It was observed that cell-free RNA levels from seven genes in the mother and the placenta could signify if the pregnancy would end pre-term. The test is said to have demonstrated 75% to 80% accuracy.
Furthermore, the researchers analysed weekly samples from 31 Danish women to develop the test for estimating gestational age.
Samples from 21 of these women were used to create a statistical model that could detect nine cell-free RNAs that are generated by the placenta and predict gestational age.
The model was then validated based on samples from the remaining ten participants. Its accuracy for the gestational age was found to be 45% and was comparable to first-trimester ultrasound estimates 48% of the time.
Stanford University postdoctoral scholar Thuy Ngo said: “This gives a super-high resolution view of pregnancy and human development that no one’s ever seen before. It tells us a lot about human development in normal pregnancy.”
The researchers intend to validate the new tests in a larger population and plan to study the genes that signal prematurity so they can gain better insights into the reason behind premature births.