An ectopic pregnancy is a condition in which the fertilized egg implants somewhere other than in the main cavity of the uterus. The word ectopic comes from a Greek word that means “out of place.”
An ectopic pregnancy is a pregnancy in which the fertilized egg (ovum) implants outside the inner lining of the womb (uterus * ), usually in one of the fallopian tubes (the tubes between each ovary * and the uterus). More rarely, an ectopic pregnancy may develop in the ovary itself, the abdomen, or the cervix * . An ectopic pregnancy is also called an extrauterine * pregnancy. An ectopic pregnancy can occur even when a woman is using birth control.
In normal pregnancies, the fertilized egg moves through the fallopian tube to the uterus, where it implants in the lining to grow and develop into a baby. When the movement of the fertilized egg is blocked by a narrow or scarred fallopian tube, it may result in an ectopic pregnancy, or implantation outside the womb. Disorders or conditions that may cause an ectopic pregnancy to occur include the following:
Additional risk factors for ectopic pregnancy include being over 35 years of age; having had many sexual partners; having had a tubal ligation (tying the fallopian tubes to prevent pregnancy); having had surgery to reverse a tubal ligation; getting pregnant while using an intrauterine device (a device to prevent pregnancy); and having had treatments for infertility (inability to get pregnant). In addition, there seems to be an association between smoking and an increased risk for ectopic pregnancy.
Ectopic pregnancy, a condition that occurs only in women of childbearing age, is not common. According to the Centers for Disease Control and Prevention (CDC), there are about 25 ectopic pregnancies for every 1,000 pregnancies in the United States as of 2016. The incidence of ectopic pregnancies in the United States has increased sixfold since 1970. The rate of ectopic pregnancy is almost twice as high in African American and Hispanic women as in Caucasian women.
A woman with an ectopic pregnancy will have all the signs of a normal pregnancy, including the absence of menstrual periods, fullness and tenderness of the breasts, and nausea and vomiting. The most common sign specific to an ectopic pregnancy is pain in the lower abdomen on the side of the pregnancy along with lower back pain. Women may feel bloated, have nausea and vomiting, and experience abnormal vaginal bleeding.
If the area where the ectopic pregnancy is located bursts because of the growing fetus in a limited amount of space, a woman may feel faint; may feel intense pressure in the rectum; may feel pain in the shoulder; and may experience severe, sharp pain in the lower abdomen. Blood pressure falls and heart rate (pulse) increases. If these symptoms occur, the ectopic pregnancy has become a life-threatening situation and the woman must seek medical care at once.
The usual treatment includes intravenous fluids and possible blood transfusion to reverse shock. Oxygen is given to ensure that oxygenated blood is provided to the body organs and tissues. A medication that stops the growth of the rapidly dividing cells of the embryo (fetus) may prevent rupture of the fallopian tube and help to expel the embryo. Surgery to remove the pregnancy from the fallopian tube is also an option, especially when the fallopian tube has ruptured. In some cases, the fallopian tube must also be removed.
In general, ectopic pregnancy cannot be prevented, but some of the risk factors associated with ectopic pregnancy can be minimized. Using safe sex practices, including taking steps to prevent getting sexually transmitted infections (STIs) that may lead to pelvic inflammatory disease, and getting early treatment for an STI, can help prevent an ectopic pregnancy. Because smoking has been associated with ectopic pregnancy, a woman planning to get pregnant or who is in her childbearing years should not smoke.
See also Infertility • Pelvic Inflammatory Disease (PID) • Pregnancy • Sexually Transmitted Infections (STIs): Overview
Beckmann, Charles R.B., et al., editors. Obstetrics and Gynecology. 7th ed. Philadelphia, PA: Lippincott Williams and Wilkins, 2014.
American Congress of Obstetricians and Gynecologists. “Frequently Asked Questions: Ectopic Pregnancy.” http://www.acog.org/Patients/FAQs/Ectopic-Pregnancy (accessed March 24, 2016).
MedlinePlus. “Ectopic Pregnancy.” U.S. National Library of Medicine, National Institutes of Health. http://www.nlm.nih.gov/medlineplus/ency/article/000895.htm (accessed March 24, 2016).
Planned Parenthood. “Ectopic Pregnancy.” http://www.plannedparenthood.org/learn/pregnancy/ectopic-pregnancy (accessed March 24, 2016).
American Congress of Obstetricians and Gynecologists. PO Box 70620, Washington, DC 20024. Toll-free: 800-673-8444. Website: http://www.acog.org/ (accessed March 24, 2016).
Planned Parenthood Federation of America. Toll-free: 800-230-PLAN. Website: http://www.plannedparenthood.org (accessed March 24, 2016).
* uterus (Yu-ter-us) is the muscular, pearshaped internal organ in a woman where a fetus develops into a baby. Also called a womb.
* ovary (oh-va-ree) is the female reproductive organ in which eggs (ova) are produced.
* cervix (SIR-viks) is the lower narrow neck of the uterus that opens into the vagina.
* extrauterine means outside the uterus or womb.