The sudden loss of a pregnancy before the 20th week.

Most miscarriages happen because an unborn baby doesn't develop properly. Risk factors include being older than 35 and having one or more previous miscarriages. Some other factors that can raise the risk are smoking tobacco, using illegal drugs, and drinking lots of alcohol or caffeine.

Miscarriage symptoms can include bleeding from the vagina with or without pain. This includes light bleeding called spotting. A pregnant person also might feel pain or cramping in the stomach or lower back. Fluid or tissue may leave the body through the vagina. The heart may beat fast.

A person who has no symptoms of a uterine infection might choose to let a miscarriage progress on its own. If the pregnancy tissue doesn't completely pass from the body, treatment with medicine or surgery is needed. If the miscarriage causes ongoing stress, anxiety or depression, counseling with a therapist can help. So can support groups.