London - A pill for diabetes could become the first ever drug to prevent miscarriages.
Around a quarter of pregnancies end in miscarriage, and one in 100 women suffer at least three in a row.
But hope is now in sight thanks to "sitagliptin", which may prevent the womb-lining from breaking down so that a woman does not lose her baby.
The daily pill recruits stem cells to the uterus, which are thought to top up others that help to keep the embryo in place.
When it was used in a trial of 38 women who had suffered repeated miscarriages, they had around two thirds more of these vital stem cells afterwards.
A year later, eight of the 16 given the drug had given birth – a slightly higher rate than the seven out of 17 given a dummy pill who had a baby afterwards.
Among those given the type 2 diabetes drug, which also helps control blood-sugar levels, just three had another miscarriage the next year compared to six not given it, according to the study in the journal EBioMedicine.
It is unclear how many couples could benefit, as many experts believe most miscarriages are caused by a problem with the fertilised egg or by the woman’s body rejecting the baby.
But Professor Jan Brosens, a co-author of the study from Warwick Medical School at Warwick University, said: "There are currently very few effective treatments for miscarriage, and this is the first that aims at normalising the womb before pregnancy." The breakthrough is based around special "decidual" cells in the lining of the womb.
Every month, to boost chances of pregnancy, the uterus gets up to 12 times thicker, which makes these cells "stressed". This inflammation is thought to be important in triggering them to surround a fertilised egg, so that it can embed firmly in the womb. But too many stressed cells pass on inflammation to others, which may cause the lining to break down, causing miscarriage.
Sitagliptin was developed to block an enzyme called DPP4, which stops the stem cells getting the chemical signal to go to the womb. Now a wider clinical trial is planned.