Miscarriage is the natural death of an embryo or fetus before it is able to survive independently. Some use the cutoff of 20 weeks of gestation after which fetal death is known as astillbirth.The most common symptoms of a miscarriage is vaginal bleeding with or without pain. Sadness, anxiety andguilt may occur.Tissue or clot-like material may also come out of the vagina.Risk factors for miscarriage include an older parent, previous miscarriage, exposure to tobacco smoke, obesity, diabetes, and drug or alcohol use, among others. In those under the age of 35 the risk is about 10% while it is about 45% in those over the age of 40.Risk begins to increase around the age of 30. About 80% of miscarriages occur in the first 12 weeks of pregnancy (the first trimester).