• An ectopic pregnancy is when a fertilized egg implants outside the uterus, most often in the fallopian tube. When an egg implants in the fallopian tube, the pregnancy cannot be carried to term because there is no room for the embryo to grow and develop. In addition, an ectopic pregnancy can also lead to serious and even life-threatening complications if the tube ruptures. According to the National Institutes of Health, ectopic pregnancies occur in between 1 in 40 and 1 in 100 pregnancies. It's important to seek proper medical attention if you think you have an ectopic pregnancy to prevent complications and also help ensure healthy future pregnancies.
  
  

Pain

• If you have an ectopic pregnancy and the fallopian tube ruptures, you will experience extreme abdominal pain. The pain is often sharp and stabbing and can be felt in the abdomen and pelvic region. In some cases, you may also experience pain in the neck and the shoulder.
  Prior to the tube rupturing, you may experience more subtle discomfort that can be a sign of an ectopic pregnancy. For example, you might have noticed some mild cramping, usually on one side of the abdomen, or some mild or moderate pain or discomfort in the lower back.
  
  

Lightheadness

• Feeling lightheaded or faint is another common sign of an ectopic pregnancy that has caused a fallopian tube to rupture. This develops because the rupture causes internal bleeding. As the bleeding continues, you may get dizzier and more lightheaded and may even faint.
  
  

Shock

• Because of the internal bleeding that occurs when an ectopic pregnancy causes the tube to rupture, shock can occur. In fact, in 20 percent of cases in which a tube ruptures, shock is the first sign, according to the National Institutes of Health. Shock is a serious condition that develops when blood is not flowing through the body properly. Common signs of shock include a rapid but weak pulse; cool, clammy and pale skin; confusion; a bluish color in the fingernails and around the lips; chest pain; rapid breathing; and sweating.
  
  

Before Rupture

• If you have an ectopic pregnancy, there are some signs you might notice before it progresses to the point that the fallopian tube may rupture. For example, you may notice some mild vaginal bleeding. Other symptoms include those that are early signs of pregnancy, such as nausea and vomiting and breast tenderness.