Multiple miscarriages 'caused by lack of stem cells in womb'

Researchers are now using their findings to try to create a treatment 

Scientists have identified why some women experience multiple miscarriages, in research they hope could be used to develop a treatment. 

A lack of stem cells in the lining of the womb causes women to miscarry repeatedly, researchers at the University of Warwick found. 

Researchers believe that the shortage makes the lining of the womb age quicker than normal, which causes the foetus to die. 

The team behind the findings will now start research into developing a treatment to help women who suffer failed pregnancies.

Between 15 to 25 per cent of pregnancies end in miscarriage. The research will give hope to the one in 100 women who experience recurrent miscarriages: defined as the loss of three or more consecutive pregnancies.

Professor of Obstetrics & Gynaecology, Jan Brosens led the team said: “We have discovered that the lining of the womb in the recurrent miscarriage patients we studied is already defective before pregnancy.

He added that treating the defects before patients try to become pregnancy again "may be the only way to really prevent miscarriages in these cases."

To make their findings published in the journal ‘Stem Cells’, researchers analysed tissue samples from the womb lining of 183 women who were being treated at the Implantation Research Clinic, University Hospitals Coventry and Warwickshire NHS Trust.

The team could not find an epigenetic signature characteristic of stem cells in the womb biopsies of women who had miscarried repeatedly. 

When compared with women who had healthy wombs, those who had multiple miscarriages also had fewer stems cells overall. 

The womb needs sufficient stem cells in order to renew itself. When cells age, it triggers an inflammatory response which may enable the embryo to be implanted but not develop.

Professor Brosens explained: "After an embryo has implanted, the lining of the uterus develops into a specialised structure called the decidua, and this process can be replicated when cells from the uterus are cultured in the lab. 

“Cultured cells from women who had had three or more consecutive miscarriages showed that ageing cells in the lining of the womb don't have the ability to prepare adequately for pregnancy.”

Siobhan Quenby, Professor of Obstetrics at University of Warwick and co-author of the study said: “The real challenge now is to develop strategies to increase the function of stem cells in the womb lining."

She said that the team will start piloting new treatments in the spring, which will focus on improving the screening of women who miscarry and improving stem cell populations in the womb lining.