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Ectopic Pregnancy


Antonette T. Dulay

, MD, Main Line Health System

Reviewed/Revised Oct 2022
Topic Resources

Ectopic pregnancy is attachment (implantation) of a fertilized egg in an abnormal location, such as the fallopian tubes.

  • In an ectopic pregnancy, the fetus cannot survive.

  • When an ectopic pregnancy ruptures, women often have abdominal pain and vaginal bleeding, which, if not treated, can be fatal.

  • Doctors base the diagnosis on results of blood tests and ultrasonography, done mainly to determine the location of the fetus.

  • Usually, surgery is done to remove the fetus and placenta, but sometimes one or more doses of methotrexate can be used to end the ectopic pregnancy.

Pregnancy complications, such as ectopic pregnancy, are problems that occur only during pregnancy. They may affect the woman, the fetus, or both and may occur at different times during the pregnancy. Most pregnancy complications can be effectively treated. In ectopic pregnancy, the fetus cannot survive, and if not diagnosed and treated promptly, ectopic pregnancy can cause life-threatening bleeding in the woman.

Normally, an egg is fertilized in the fallopian tube and becomes implanted in the uterus. However, if the tube is narrowed or blocked, the fertilized egg may never reach the uterus. Sometimes the fertilized egg then implants in tissues outside of the uterus, resulting in an ectopic pregnancy. Ectopic pregnancies usually develop in one of the fallopian tubes (as a tubal pregnancy) but may develop in other locations.

A fetus in an ectopic pregnancy sometimes survives for several weeks. However, because tissues outside the uterus cannot provide the necessary blood supply and support, ultimately the fetus does not survive. The structure containing the fetus typically ruptures after about 6 to 16 weeks, long before the fetus is able to live on its own. When an ectopic pregnancy ruptures, bleeding may be severe and even threaten the life of the woman. The later the structure ruptures, the worse the blood loss, and the higher the risk of death. However, if an ectopic pregnancy is treated before it ruptures, the woman rarely dies.

About two of 100 pregnancies are an ectopic pregnancy.

Risk factors (conditions that increase the risk of a disorder) that particularly increase the risk for an ectopic pregnancy include

Pregnancy is less likely to occur after tubal ligation is done or when an IUD is in place (fewer than 1.5% of women become pregnant). However, if pregnancy does occur, about 5% of them are ectopic.

Other risk factors for ectopic pregnancy include

Ectopic Pregnancy: A Mislocated Pregnancy

Normally, an egg is fertilized in the fallopian tube and becomes implanted in the uterus. However, if the tube is narrowed or blocked, the egg may move slowly or become stuck. The fertilized egg may never reach the uterus, resulting in an ectopic pregnancy.

An ectopic pregnancy may be located in many different places, including a fallopian tube, an ovary, the cervix, and the abdomen.

Ectopic Pregnancy: A Mislocated Pregnancy

Symptoms of Ectopic Pregnancy

Symptoms of ectopic pregnancy vary and may not occur until the structure containing the ectopic pregnancy ruptures. Most women have vaginal bleeding or spotting and/or pain. which may be dull, sharp, or crampy, in the lower abdomen. Menstrual periods may or may not be late or missed. Some women do not suspect that they are pregnant.

When the structure ruptures, the woman usually feels sudden, severe, constant pain in the lower abdomen. If the woman has significant blood loss, she may faint, sweat, or feel light-headed. These symptoms may indicate that she has lost so much blood that she has dangerously low blood pressure (shock Shock Shock is a life-threatening condition in which blood flow to the organs is low, decreasing delivery of oxygen and thus causing organ damage and sometimes death. Blood pressure is usually low... read more ). She may develop peritonitis Peritonitis Abdominal pain is common and often minor. Severe abdominal pain that comes on quickly, however, almost always indicates a significant problem. The pain may be the only sign of the need for surgery... read more (inflammation of the membrane that lines the abdominal cavity).

Diagnosis of Ectopic Pregnancy

  • A pregnancy test

  • Ultrasonography

  • Blood tests

  • Sometimes laparoscopy

Doctors suspect an ectopic pregnancy in women who are of childbearing age and who have lower abdominal pain or vaginal bleeding, faint, or go into shock. In such women, a pregnancy test is done.

Because a ruptured ectopic pregnancy causes bleeding and increases the risk of death in the woman, prompt diagnosis is essential.

If the pregnancy test is positive or, rarely, if the test is negative but symptoms still suggest ectopic pregnancy, ultrasonography is done using a handheld device inserted into the vagina (called transvaginal ultrasonography). If ultrasonography detects a fetus in a location other than its usual place in the uterus, the diagnosis is confirmed. If ultrasonography does not detect a fetus anywhere, ectopic pregnancy is still possible, or the pregnancy may be in the uterus but be so early that it cannot be seen.

Doctors also do blood tests to measure a hormone produced by the placenta early in pregnancy called human chorionic gonadotropin (hCG). This test can help doctors determine whether the pregnancy is too early for the fetus to be visible in the uterus or is an ectopic pregnancy.

If needed to confirm the diagnosis, doctors may use a viewing tube called a laparoscope, inserted through a small incision just below the navel. This procedure enables them to view an ectopic pregnancy directly.

If tests do not confirm a diagnosis of ectopic pregnancy and the woman has no serious problems, hCG levels in the blood are measured periodically. This level normally increases fairly rapidly. If hCG levels do not increase as expected or decrease, an ectopic pregnancy (or miscarriage) is likely.

Treatment of Ectopic Pregnancy

  • Usually, methotrexate for small, unruptured ectopic pregnancies

  • Surgery

  • Sometimes the drug methotrexate

An ectopic pregnancy must be ended as soon as possible to save the life of the woman.

For small ectopic pregnancies that have not ruptured, one dose of the drug methotrexate, given by injection, can usually be used instead of surgery. The drug causes the ectopic pregnancy to shrink and disappear. After the drug is given, doctors do blood tests to measure hCG levels every week to determine whether treatment with methotrexate was successful. If hCG cannot be detected, treatment is considered successful. If methotrexate was unsuccessful, a second dose of methotrexate or surgery is needed.

The fetus and placenta are removed surgically if doctors suspect the ectopic pregnancy has ruptured or if treatment with methotrexate is not indicated—for example, if the woman's blood test results are abnormal.

If the woman is having serious problems (such as bleeding or shock), doctors immediately remove the ectopic pregnancy by making an incision in the abdomen (laparotomy).

If the woman is not having serious problems, doctors usually insert a viewing tube (laparoscope Laparoscopy Sometimes doctors recommend screening tests, which are tests that are done to look for disorders in people who have no symptoms. If women have symptoms related to the reproductive system (gynecologic... read more Laparoscopy ) into the abdominal cavity through a small incision just below the navel and use instruments threaded through the laparoscope to remove the ectopic pregnancy.

During surgery, doctors remove the fetus and placenta and only the part of the fallopian tube that cannot be repaired. This approach increases the chance that repairing the fallopian tube can enable women to become pregnant. However, sometimes the tube cannot be repaired.

Rarely, the uterus is so damaged that a hysterectomy is required.

Ectopic Pregnancy

Drugs Mentioned In This Article

Generic Name Select Brand Names
Otrexup, Rasuvo, RediTrex, Rheumatrex, Trexall, Xatmep
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