The diagnosis can be made after the loss of two or more pregnancies. It is uncommon and occurs in about 1% to 2% of women. Although there are several known causes, the cause may not be obvious in up to 50% of women.
Some causes include but are not limited to advanced maternal age, antiphospholipid syndrome; cervical insufficiency; congenital malformations of the uterus or acquired problems such as fibroids or polyps inside the uterine cavity; genetic disorder; uncontrolled maternal disease such as thyroid disease and diabetes; poor lifestyle choices leading to obesity, smoking, etc. It is important for a couple to be evaluated together to find any correctable cause. It is best to be evaluated first before embarking on another pregnancy.