Ectopic pregnancy
Ectopic pregnancy occurs when a fertilized embryo implants outside the uterine cavity, most commonly in a Fallopian tube, leading to potential complications. The exact causes of ectopic pregnancies remain largely unknown, but several risk factors have been identified, including previous pelvic inflammatory disease, tubal surgeries, and conditions such as endometriosis. Symptoms often mimic early pregnancy and may include spotting, cramping, and localized abdominal pain, with the risk of severe complications like internal bleeding if the Fallopian tube ruptures. Ectopic pregnancies account for about 1 in every 50 pregnancies in the U.S., predominantly as tubal pregnancies, which are the most dangerous. While some cases can be managed with methotrexate to halt the pregnancy early on, surgical intervention is often necessary, particularly if the pregnancy is detected later or if complications arise. Timely diagnosis through transvaginal ultrasounds and blood tests is crucial for effective management. It is important for women experiencing symptoms of ectopic pregnancy to seek medical attention promptly to avoid serious health risks.
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Subject Terms
Ectopic pregnancy
ALSO KNOWN AS: Tubal pregnancy, abdominal pregnancy
ANATOMY OR SYSTEM AFFECTED: Reproductive system
DEFINITION: The implantation of an embryo outside the uterine endometrium, most commonly in the Fallopian tube.
CAUSES: Unknown; factors may include previous pelvic inflammatory disease, IUD use, tubal ligation, endometriosis, multiple abortions, pelvic adhesions
SYMPTOMS: Similar to those of early pregnancy, followed by spotting, cramping, abdominal pain (especially on one side); if Fallopian tube ruptures, bleeding, severe pain, low blood pressure, and fainting can occur; in some cases rupture can be fatal
DURATION: Acute
TREATMENTS: Only in early cases, methotrexate to end pregnancy; usually abortion, which allows surgical removal of embryo
Causes and Symptoms
Although ectopic pregnancies can occur without any known cause, several factors increase a woman’s risk. Studies have shown an increase in ectopic pregnancies in women with previous pelvic inflammatory disease (PID). Intrauterine devices (IUDs), so effective at preventing pregnancies, do not increase the risk of ectopic pregnancy. However, when a woman with an IUD does get pregnant, the risk for an ectopic pregnancy is increased, especially for women using an IUD containing progestin at the time of conception. There is also an increased risk in women who have had tubal ligations and other surgeries of the Fallopian tubes.
Endometriosis, multiple induced abortions, fertility treatments, anatomical abnormalities in the uterus or Fallopian tubes, and pelvic adhesions also may increase a woman’s chance of ectopic pregnancy. In general, women whose Fallopian tubes are damaged for any reason have a higher risk. The risk is heightened because damage slows the progress of the developing through the tube, allowing the embryo to be mature enough to implant itself before reaching the uterus. Another factor that may increase the chances of ectopic is smoking. Nicotine slows the movement of in the Fallopian tubes, thus slowing the progress of the embryo.
In the US, roughly one in fifty pregnancies are ectopic. Although 95 percent of ectopic pregnancies are tubal pregnancies, which are the most dangerous form of ectopic pregnancies, rarer types of ectopic pregnancies can occur. These include cervical pregnancies, when embryos implant in the endocervical canal's mucosa, and ovarian pregnancies, when the gestational sac implants in an ovary.
The symptoms of an early ectopic pregnancy are similar to those of any early pregnancy, except that spotting, cramping, and pain, especially on only one side of the abdomen, may occur as the embryo grows. Hormone levels mimic early pregnancy but usually do not rise as high as in a normal intrauterine implantation.
If an ectopic pregnancy is left untreated and the fallopian tube ruptures, bleeding, severe pain, low blood pressure, and fainting may occur. Ruptures can be fatal; during the early 2020s, ruptures caused by ectopic pregnancies were the leading cause of maternal death during the first trimester of pregnancy and accounted for a total of 5 to 10 percent of all pregnancy-related deaths in the US. While chemicals can be used to resolve ectopic pregnancies when they are detected early enough, surgical abortion is typically necessary in cases when the embryo grows large enough to cause or risk a rupture.
Transvaginal ultrasounds and blood tests, along with physical examination, are often used to determine the presence of an ectopic pregnancy.
Treatment and Therapy
If a tubal ectopic pregnancy is diagnosed early enough, methotrexate, a chemical that attacks quickly growing cells, may be administered via injection, and surgery may be avoided. The drug causes the death of the embryo. Surgical removal via an emergency abortion is now less common than is management with methotrexate; when surgery is performed, it is usually done through laparoscopy. In conservative surgery, the Fallopian tube is preserved, while in radical surgery, it is removed. Following surgery, may be administered to help remove any remaining tissues from the pregnancy. Because there is no known way to implant the removed embryo in the uterus, surgical removal also results in the death of the embryo. For shock associated with tubal rupture, treatments may include intravenous fluids, oxygen, and blood transfusion.
Bibliography
American Academy of Family Physicians. "Ectopic Pregnancy." FamilyDoctor.org, January 2011.
"Ectopic Pregnancy." Mayo Clinic, 12 Mar. 2022, www.mayoclinic.org/diseases-conditions/ectopic-pregnancy/symptoms-causes/syc-20372088. Accessed 1 Apr. 2024.
"Ectopic Pregnancy." National Library of Medicine, 8 Aug. 2023, www.ncbi.nlm.nih.gov/books/NBK539860/. Accessed 21 May 2024.
Leach, Richard E., and Steven J. Ory, eds. Management of Ectopic Pregnancy. Malden, Mass.: Blackwell Science, 2000.
Mullany, Kellie, et al. "Overview of Ectopic Pregnancy: Diagnosis, Management, and Innovation." Women's Health, vol. 19, 31 Mar. 2023, doi.org/10.1177%2F17455057231160349. Accessed 1 Apr. 2024.
Preidt, Robert. "Ultrasound Best Detector of Dangerous Ectopic Pregnancies, Study Finds." HealthDay, April 23, 2013.
Ries, Julia. "Ectopic Pregnancies Are Dangerous. Will They Be Affected by Abortion Bans?" Healthline, 11 May 2022, www.healthline.com/health-news/ectopic-pregnancy-and-abortion-laws-what-to-know. Accessed 21 May 2024.