Miscarriage is defined as the loss of a pregnancy before 20 weeks of gestation. Nearly 20% of pregnancies end in miscarriage, most often within the first 12 weeks. Recurrent miscarriage, or habitual pregnancy loss, is defined as three or more consecutive, spontaneous pregnancy losses.
Often no cause for miscarriages is found but possible causes include genetic defects, abnormally shaped uterus, uterine fibroids, scar tissue, hormonal imbalances and illness such as diabetes. Increased age, habits such as smoking, caffeine and alcohol, and the use of certain medications increase a woman's risk for miscarriage.

There are a number of tests that your physician may run, in addition to reviewing your medical history and conducting a pelvic exam, to diagnose the possible cause of your recurring miscarriages. These tests may include a mapping of your chromosomes to detect genetic defects, a hysterosalpingogram, blood tests to detect immune system abnormalities and measure hormone levels, a vaginal ultrasound and an endometrial biopsy. Once the cause has been determined, your physician will work with you to map out a treatment plan, which may include surgery to correct problems with the shape of the uterus or medication to correct immune problems and hormone imbalances.

Treatment increases your chances of becoming pregnant and carrying a pregnancy to term. However, even if no cause is found and no treatment is given your chances of eventually delivering a baby after recurring miscarriages is about 60%.