According to British scientists, a lack of stem cells in the lining of the womb is one of the main causes of recurrent miscarriages. There may be hope, however, as the researchers also believe that an existing diabetes medication could help remedy the situation.
The new study, conducted by a team from the University of Warwick, indicated that stem cells both improve renewal of the womb lining, and reduce inflammation in the early stages of pregnancy. Both of these factors contribute toward a more nurturing environment for the embryo.
Problems occur when not enough stem cells are present in the womb, due to overactivity of a certain naturally-occurring enzyme. That's where the diabetes drug, known as sitagliptin, comes into the picture.
"The enzyme, DPP4, is involved in breaking down the signal generated by the lining of womb to recruit bone marrow-derived stem cells from the blood," lead scientist Prof. Jan Brosens tells us. "Sitagliptin inhibits DPP4, thus amplifying the signal generated by the lining of the womb following menstruation, and thereby increasing recruitment of stem cells."
In a pilot clinical trial conducted by Brosens and colleagues, a total of 38 women aged 18 to 42 were selected, all of whom had experienced a large number of recurrent miscarriages. Approximately half of those women received oral doses of sitagliptin over the course of three menstrual cycles, while the other half got a placebo – needless to say, neither group knew which one they were getting.
When samples were subsequently obtained from all the test subjects, it was found that women taking the drug experienced a 68-percent average increase in stem cells in the womb lining, while the control group saw no significant increase. Few side effects were noted.
Additionally, the sitagliptin group had a 50-percent decrease in the number of "stressed" decidual cells in the womb lining. Decidual cells provide the embryo with nutrients, and according to the U Warwick team, stem cells in the womb lining protect deciduals from stress and inflammation – allowing them to better do their job.
"There are currently very few effective treatments for miscarriage and this is the first that aims at normalizing the womb before pregnancy," says Brosens. "Although miscarriages can be caused by genetic errors in the embryo, an abnormal womb lining causes the loss of chromosomal normal pregnancies. We hope that this new treatment will prevent such losses and reduce both the physical and psychological burden of recurrent miscarriage."
A large-scale clinical trial is now being planned. The research is described in a paper that was recently published in the journal EBioMedicine.
Source: University of Warwick