An ectopic pregnancy is any pregnancy that implants in a site other than the uterine cavity. During a normal pregnancy, an egg becomes fertilized by a sperm inside the fallopian tube. The fertilized egg travels down through the fallopian tube and into the uterus, where it implants on the inside wall. An ectopic pregnancy occurs when the embryo implants outside the uterus. In most cases, ectopic pregnancies occur in the fallopian tube—a fertilized egg becomes trapped there and implants. Although more rare, ectopic pregnancies can also occur in other places such as on an ovary, within the cervix, or in the abdomen.
Symptoms of an ectopic pregnancy include irregular vaginal bleeding after a missed period, lower abdominal pain, lower back pain and sometimes shoulder pain. If you have these symptoms you should call your doctor right away as it can be a life threatening emergency if it is not diagnosed and treated early. The implanting embryo can cause the fallopian tube to rupture and bleed leading to severe uncontrolled internal bleeding.
The causes of an ectopic pregnancy is often unknown but is thought to occur if the tube has been damaged in some way for example infections, endometriosis, previous tubal surgery, or some hormone therapy. Scar tissue inside the fallopian tube can trap the fertilized egg resulting in an ectopic pregnancy. It is also a rare complication of fertility treatments and IVF.