Could the days of patiently waiting for a baby to make its appearance known be a thing of the past? It might well be as scientists have recently developed a blood test that could give more accurate birth dates to expectant parents.
Currently, due dates are confirmed around after the 12 week scan, with most women giving birth between 37 and 42 weeks of pregnancy, with due dates often off the mark by weeks for many.
However, a simple blood test which has the ability to indicate the 'pre-labour' stage from between two to four weeks before a baby is born has been developed by scientists in the US. The analysis is able to detect the pre-labour surge in hormones which sees a reduction in blood cell formation as the placenta prepares to break away from the womb, and various immune cells and proteins.
In the trial, the blood test was performed on 63 women and could predict the day a full-term woman would go into labour within 17 days. Researchers hope that accuracy will improve if the blood test is rolled out to larger numbers and hope it will be widely available for pregnant women within two years.
The co-author of the study and associate professor of obstetrics and gynaecology at Stanford University, Dr Virginia Winn, said: "The mother's body and physiology start to change about three weeks before the actual onset of labour.
"It's not a single switch - there's this preparation that the body has to go through."
Using blood samples from 63 pregnant women who all gave birth naturally without being chemically induced, researchers were able to analyse for more than 7,000 biological markers which might help to predict their due dates.
They were able to identify 45 which were of vital importance, including the surge of progesterone. The study also found that a regulatory immune protein, IL-1R4, spikes during the 30 days before labour, as well as the decrease of certain proteins which help the placenta form as it begins to separate the blood supply from the womb.
The study, which is published in the journal Science Translational Medicine, also saw scientists predict the due dates for five women who unexpectedly gave birth early before 37 weeks, something that could help medical experts manage premature births more robustly.
Dr Ina Stelzer, lead author of the study from Stanford University, said: "We found a transition from 'progressing pregnancy' to a 'pre-labour' phase that happens two to four weeks before the mother goes into labour.
"We've identified a novel way to use the maternal blood to predict when a mother will go into labour."
