Abortion can be spontaneous (miscarriage) or induced (therapeutic) and occurs before 20 weeks of pregnancy. The most common causes of miscarriage are fetal abnormalities, placental issues, and maternal health factors. Therapeutic abortions in the first trimester include medical abortions using drugs like mifepristone and misoprostol or surgical abortions using vacuum aspiration. Risks increase in the second trimester where induced labor or other procedures are used. Complications, while rare, can include infection, bleeding and injury.