New research has suggested that a drug already in use for type 2 diabetes might also help prevent recurrent miscarriages.
Previous research from the University of Warwick had found that a lack of stem cells in the womb could be responsible for thousands of women having recurrent miscarriages, which is the loss of two or more consecutive pregnancies in the first 24 weeks.
The team found that these stem cells are important for pregnancy as they protect another type of specialised cells, called decidual cells, which surround the embryo. Excessive stress on decidual cells can cause the womb lining to breakdown, leading to placental bleeding and miscarriage.
Following on from this finding, the team has now published a paper in the journal EBioMedicine reporting that an already known diabetes drug called sitagliptin can increase the number of these all-important stem cells.
Sitagliptin inhibits an enzyme called DPP4, which affects the circulation of stem cells in the womb. In doing so, the team believes the drug can better prepare the womb lining for pregnancy.
The team tested the effect of sitagliptin in a pilot clinical trial including 38 women aged 18 to 42, each of whom had experienced recurrent miscarriages - five on average. Participants were given either an oral course of sitagliptin or a placebo for three menstrual cycles.
Biopsies of the womb were taken at the start of the course of treatment and afterwards, in order to determine if the drug had altered the number of stem cells in the womb.
The researchers found an average increase in stem cell count of 68 percent in women who took the full course of sitagliptin, compared to no significant increase in those who took the placebo. They also saw that those taking sitagliptin had a 50 percent decrease in the number of 'stressed' decidual cells.
Of the 38 women who took part, two have also gone on to have successful pregnancies.
However, one of the researchers, Professor Siobhan Quenby, from Warwick Clinical Trials Unit and an Honorary Consultant at University Hospital Coventry and Warwickshire NHS Trust, has warned that while the results are very exciting, it is too early to say if the drug can prevent miscarriages in a large number of women.
She said, 'These are very early results and the treatment now needs to be further tested in a large-scale clinical trial.'
This was echoed by Jane Brewin, Chief Executive at Tommy's who funded the work. She said, 'This breakthrough research by the world leading team at Warwick shows great promise for an effective treatment which will reduce miscarriage and possibly later pregnancy loss too. A large-scale trial is needed to verify the findings and we hope that this will get underway quickly.'
If successful, sitagliptin would be the first drug targeted specifically at the lining of the womb to prevent miscarriage. However, it would not be useful for other causes of miscarriage, such as those caused by abnormalities in the developing baby.