An ectopic pregnancy occurs when the fertilized egg attaches itself in a place other than inside the uterus. Almost all ectopic pregnancies occur in a fallopian tube, and are thus sometimes called tubal pregnancies. The fallopian tubes are not designed to hold a growing embryo; the fertilized egg in a tubal pregnancy cannot develop normally and must be treated. An ectopic pregnancy happens in 1 out of 60 pregnancies.
What causes an ectopic pregnancy?
Ectopic pregnancies are caused by one or more of the following:
An infection or inflammation of the fallopian tube can cause it to become partially or entirely blocked.
- Scar tissue left behind from a previous infection or an operation on the tube may also impede the egg's movement.
- Previous surgery in the pelvic area or on the tubes can cause adhesions.
- An abnormality in the tube's shape can be caused by abnormal growths or a birth defect.
Who is at risk for having an ectopic pregnancy?