Certified Obstetric Emergencies (C-OBE) Practice Exam

The main idea here is where ectopic pregnancies most often implant. The ampulla is the site where implantation occurs most frequently because it is the widest, longest segment of the fallopian tube and the place where the fertilized egg typically resides during normal transport. When tubal motility is slowed or there is tubal pathology, implantation is most likely to happen there. As a result, about seven to eight out of ten ectopic pregnancies occur in the ampulla. The other locations in the tube or nearby structures are much less common, which is why they account for a smaller percentage.