An ectopic pregnancy occurs when a fertilized egg attaches
somewhere other than in the uterus, usually in a fallopian tube (tubal
pregnancy). Because an ectopic pregnancy can cause life-threatening
complications, the pregnancy must be ended with medicine or surgery.
When a fertilized egg attaches to a fallopian tube, it can be
dangerous because the pregnancy can break into blood vessels. If a tubal
pregnancy is not detected and treated early, the blood vessels may burst. This
can be a life-threatening situation and requires emergency surgery.
Pelvic inflammatory disease or tubal surgery increases the risk of
having an ectopic or tubal pregnancy by creating scar tissue that may block the
fallopian tube.