Recurrent pregnancy loss (RPL), commonly referred to as recurrent miscarriage, affects approximately 1-2% of couples attempting to conceive. In nearly half of these cases, no definitive cause can be identified despite thorough clinical evaluation. A circumstance that is both distressing and disorienting for affected families, particularly in settings such as the United Arab Emirates (UAE), where childbearing carries significant personal and cultural weight.

One leading hypothesis is that the underlying problem may not lie with the embryo itself, but with the way the mother's immune system responds to a developing pregnancy. Under normal physiological conditions, the maternal body must establish immune tolerance toward an embryo that is genetically half-foreign in origin. In some women, this tolerance mechanism may be impaired, reducing the likelihood that a pregnancy will successfully implant and progress.

This study will evaluate whether granulocyte colony-stimulating factor (G-CSF) a naturally occurring substance that normally stimulates the production of immune cells can help address this issue by modulating an overactive immune response and enhancing the uterine environment's capacity to support pregnancy. Notably, the study will enroll only women whose embryos have undergone genetic testing and been confirmed to be chromosomally normal. This eliminates embryo quality as a contributing factor to pregnancy loss and allows for a clearer assessment of whether G-CSF itself influences outcomes.

Earlier small-scale studies, including preliminary work conducted at our own centre, have shown encouraging results. This new trial builds on that foundation by enrolling a larger cohort, comparing G-CSF against a placebo (an inactive comparison treatment), and evaluating a simpler route of administration; subcutaneous injection, rather than direct infusion into the uterus. Together, these design features aim to provide the most reliable evidence to date on whether this treatment can meaningfully help couples affected by unexplained recurrent pregnancy loss.