In a normal pregnancy, the fertilised egg implants in the wall of the uterus (womb). However, in an Ectopic Pregnancy, it implants outside the uterus, most often in one of the fallopian tubes. The pregnancy is unable to develop a proper blood supply, so it can not survive. As it grows, it can lead to rupture (bursting) of a fallopian tube, which may lead to internal bleeding- this can be life-threatening. About 15% of Ectopic Pregnancies first present when they have ruptured, but in most situations they present with symptoms such as pelvic pain,  lower back pain or light vaginal bleeding/ spotting.