Hello and welcome to eHealth forum!
Since you have a history of miscarriages, and are now having cramps, rush to urgent cae or gynecologist to rule out threatened abortion. Generally first trimester abortions or abortions occurring in first three months are due to fetal abnormality, genetic causes, Rh blood group incompatibility and low progesterone hormone. Infection of the uterus, endometriosis, fibroids, etc are some other causes for early abortion.
You need to consult your gynecologist and run some tests to rule out these causes. Hope this helps. Take care!