Because the underlying cause of most miscarriages is chromosomal abnormalities, the various therapies and techniques typically promoted for prevention are not proven and are unlikely to be useful. This includes over the counter, herbal, and alternative treatments.

Treatable Causes
Occasionally, a patient is diagnosed with a medical condition that may cause or contribute to recurrent miscarriage. Treatment or correction of the underlying disease, deficiency, or abnormality may reduce the chance of future miscarriage for some patients.

A high percentage of fertile women who have unprotected sex will experience loss of a pregnancy at some point. According to the American Society for Reproductive Medicine, 25% of recognized pregnancies end in miscarriage.

The total number of miscarriages (including cases where the woman is unaware of the pregnancy) is estimated at about 50%. Pregnancy losses occurring within the first 8 weeks are most common. Few women experience miscarriage after the 12th week.