A pregnancy that can't be carried to term because the fertilized egg grows outside the uterus.

With an ectopic pregnancy, the fertilized egg can't survive. And it can cause life-threatening bleeding without treatment. The most common type of ectopic pregnancy involves one of the fallopian tubes, which eggs pass through on the way to the uterus. Hormones or how the egg develops may play roles too.

Light bleeding from the vagina and pain in the pelvis are often the first symptoms of an ectopic pregnancy. Shoulder pain can occur if blood leaks from the fallopian tube. Get medical help right away for symptoms such as serious belly or pelvic pain with vaginal bleeding, extreme dizziness or fainting, or shoulder pain.

Treatment can prevent life-threatening problems. Some early ectopic pregnancies are treated with medicine called methotrexate, which stops cell growth and dissolves existing cells. Other times, surgery is needed to remove the ectopic tissue or stop heavy bleeding. The right treatment depends on the symptoms and when the ectopic pregnancy was found.