The vast majority of women who miscarry go on to have a successful pregnancy next time. Recurrent miscarriages (three or more miscarriages in a row) occur in about 1 in 100 women. What causes miscarriage? It is thought that most early miscarriages are caused by a one-off problem with the chromosomes of the developing baby (fetus) in the womb. Chromosomes are the structures that contain the genetic information that we inherit from our parents.