Chemical signs that says baby is coming

By Colin Fernandez

For years, timing when a pregnant woman is about to go into labour has been something of a mystery.

It can strike at any time of the day and night and the first a woman knows it will happen is when her waters break and contractions start.

Doctors offer a woman a due date – based on a measurement of how dilated the neck of the womb is – but often this can be out by weeks.

But now researchers believe they have found a chemical sign that could tell doctors when women are about to go into labour.

Doctors hope that the knowledge will lead to tools that can predict when labour will take place – and even how to prevent or trigger labour from occurring.

Tests on the cells in the amniotic fluid – which surrounds the baby in the womb – can indicate when a woman is ready to give birth.

Scientists at The University of Texas Medical Branch at Galveston analysed fluid samples from 50 women in labour and 51 women at the end of their pregnancy – but not yet in labour.

They then compared the differences between cell fragments found in the fluid to discover what triggered the change that begins labour, as well as membranes in placentas of women after they gave birth.

They found biological markers show when labour is about to start.

As labour approaches, structures in the womb such as the placenta, an organ attached to the womb lining which supplies the baby with blood, come to the end of their lifespan.

Tiny bits breaking off the placenta called telomeres, which float freely in the fluid become shorter and more fragmented as pregnancy goes on.

When they are at their most fragmented, they indicate labour is about to start.

The team, who published their research in PLOS ONE think these telomeres trigger the process of inflammation that leads to labour.

Lead author Ramkumar Menon, a professor of obstetrics said: ‘The initiation of the birthing process is complex. Several body systems maintain pregnancy through a delicate balance – altering this balance tends to promote labour.

He added: ‘We know from previous studies that inflammation can alter the balance of the mother’s hormones in the uterus, triggering the labour process.’

Telomeres are the parts of the DNA that protect our genetic data while cells are dividing.

These telomeres become shorter every time a cell divides, which hinders their ability to ensure that the new cells are identical to the parent cells.

This shortening process is linked with the changes that take place in our bodies as we age.