Ectopic is another way of saying "out of place". An ectopic pregnancy occurs when the fertilized egg implants itself somewhere outside of the uterus. Although most ectopic pregnancies occur in the fallopian tubes, embryos can also implant in the ovaries, abdomen or cervix. None of these sites will provide the fertilized egg with enough space or nutrients to properly develop, and the resulting fetus will eventually rupture the space that it inhabits, usually causing extensive bleeding that will endanger the mother's life.

Since most early pregnancy symptoms, missed periods, nausea and breast tenderness, also occur in ectopic pregnancies, these pregnancies can be difficult to detect. However, pain can be the first indication of a problem, and blood loss from the rupture of the implantation site also causes low blood pressure, dizziness or fainting. Some ectopic pregnancies present with lower back pain and sharp pain in the pelvis or abdomen.

A quantitative blood test to measure the traces of the human chorionic gonadotropin hormone (HCG) in the blood is often used in the initial diagnosis. If the hormone levels are lower than expected, an ectopic pregnancy may be the cause. The blood test is often followed with a pelvic or ultrasound exam to check for the presence of the developing fetus in the uterus. Another test, called a culdoncentesis, is used to check for internal bleeding and involves the insertion of a needle into the top of the vagina and behind the uterus. Blood present in this area is usually caused by a ruptured ectopic pregnancy.

Treatments for this type of pregnancy vary depending on the location and size. Methotrexate can be injected into the earliest stages of the pregnancy to dissolve the fertilized egg. However, as the pregnancy progresses, laparoscopy or surgery may be needed to remove the fetus.