New blood tests could soon reveal when pregnant women will give birth

I went 10 days over my due date with both of my babies.

Anyone who has been in the same boat knows how nerve-wracking this waiting game can be –literally now knowing is THIS is going to be the day. In fairness, I think the past couple of weeks of pregnancy is like this to everyone – in equal measure terrifying and amazing – is TODAY the day you get to meet your baby? However, this game of wondering when you go into labour could soon be a thing of the past.

A simple blood test that 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.

"The mother's body and physiology start to change about three weeks before the actual onset of labour," said co-author of the study and associate professor of obstetrics and gynaecology at Stanford University, Dr Virginia Winn.

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.

According to the study, which was published in the journal Science Translational Medicine, the researchers were able to identify 45 of these markers 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. Even more interestingly, the researchers were also, thanks to the blood tests, able to predict the due dates for five women who unexpectedly gave birth early (before 37 weeks), something that could help medical experts predict and manage premature births better and more efficiently in the future.

"We found a transition from 'progressing pregnancy' to a 'pre-labour' phase that happens two to four weeks before the mother goes into labour," said Dr Ina Stelzer, lead author of the study from Stanford University.

"We've identified a novel way to use the maternal blood to predict when a mother will go into labour."