Ultrasound image showing an ectopic pregnancy occurring in the right Fallopian tube. The position of the eight week old embryo is outlined by the markers seen at centre. In ectopic pregnancies the embryo implants outside the uterus and most commonly this occurs in the Fallopian tubes or, more rarely, in the abdominal cavity or cervix. As the pregnancy develops the enlarging embryo may damage or rupture the surrounding tissues causing serious bleeding. Once discovered ectopic pregnancies require emergency treatment. An operation is performed to remove the embryo and the Fallopian tube, if this may not be repaired.