There’s an old adage in emergency medicine that was taught to me by a wise, old physician. It’s not very poetic, but remembering it can save lives. It goes that “Any abdominal pain in a female patient of childbearing age is an ectopic pregnancy until proven otherwise.” It’s wise advice to follow for all EMS providers, but why is that?
In a normal pregnancy, the fertilized egg enters the uterus and settles into the uterine lining where it has plenty of room to divide and grow. However, in about 1% of pregnancies the egg implants in an improper or “ectopic” location. An “ectopic pregnancy” (or “eccysis”) is a condition where the embryo implants outside of its normal place within the uterine cavity. Ectopic pregnancies are nearly always non-viable and are extremely dangerous for the mother as they can cause severe internal hemorrhage as they continue to grow. Most ectopic pregnancies occur in the Fallopian tubes, but implantation of the ectopic embryo can occur in the cervix, ovaries, and even inside the abdominal cavity. This is a true medical emergency that can be fatal without rapid diagnosis and treatment.
The biggest risk to the mother from an ectopic pregnancy is internal hemorrhage which can rapidly cause nearly total exsanguination. Since development of the embryo requires a large blood supply, the developing embryo impinges upon the local blood vessels in the tissues in which it has implanted. Growth of the embryo in these ectopic locations can also rupture the structures they’re growing inside such as the fallopian tube. Due to the vascularity of the developing embryo, should a rupture occur the internal bleeding can be very severe. The condition can also cause vaginal bleeding should the blood vessels rupture inside of the birth canal and leak into the uterine space or the lumen of the fallopian tube. In some cases, vaginal bleeding causes the ectopic pregnancy to be flushed out of the reproductive tract and is a common form of miscarriage. A percentage of ectopic pregnancies resolve themselves in this manner. However, should this not happen, prompt medical or surgical intervention is needed.
Early symptoms of an ectopic pregnancy are subtle or even absent with clinical presentation occurring on average of around 7.2 weeks after the last normal menstrual period. The normal range for symptom appearance is 5 to 8 weeks after the last normal menstruation. The presence or absence of proper prenatal care plays a role on when the symptoms are first noticed.
Early signs of an ectopic pregnancy include:
- Pain in the lower abdomen that may feel like a strong cramp
- Pain while urinating and/or having a bowel movement
- Vaginal bleeding that is usually mild. It could be confused with bleeding from an early miscarriage or the “implantation bleed” of normal, early pregnancy
Late signs of an ectopic pregnancy include pain and bleeding. The bleeding will be both external vaginal and internal:
- External bleeding is generally due to falling progesterone levels
- Internal bleeding or “hematoperitoneum” is due to hemorrhage from the affected tube.
More severe internal bleeding may cause:
- Lower back, abdominal, or pelvic pain.
- Shoulder pain caused by free blood tracking up inside the abdominal cavity and irritating the diaphragm. This is a late and very ominous sign.
- Cramping or tenderness on one side of the pelvis.
Consider ectopic pregnancy in cases where abdominal pain is of sudden onset and is getting worse. Remember that since an ectopic pregnancy may mimic the symptoms of other diseases and also of less serious causes of abdominal pain, such as appendicitis, some gastrointestinal disorders, problems of the urinary system, pelvic inflammatory disease (PID), and other gynecologic problems providers should not quickly dismiss such symptoms as non-life-threatening complaints. Since the condition can rapidly deteriorate into severe internal hemorrhage that can be rapidly fatal, prompt treatment and a high index of suspicion is warranted.
To see a case review covering Abdominal Pain of another cause for EMS, see: "Appendicitis – An EMS Case Review"