IVF does not contribute to miscarriages.
The two most common causes for early pregnancy loss are an implantation dysfunction (where the uterus is not receptive to the embryo) or a genetic abnormality of the embryo itself.
One of the most common reasons why IVF is unsuccessful, or why miscarriages occur, is because of chromosomal variations in the embryo. Up to 70% of embryos, whether created naturally or through IVF, are lost before birth. This usually occurs within the first three months of pregnancy, most often before implantation.