What is the leading cause of ectopic pregnancy?

The leading cause of ectopic pregnancy is adhesions, often resulting from previous pelvic infections, surgical scars, or endometriosis. These adhesions can create an abnormal environment in the fallopian tubes, making it difficult for a fertilized egg to travel through the tube to the uterus, thereby leading to implantation in the tube itself. Conditions that cause pelvic inflammatory disease, such as sexually transmitted infections, can also contribute significantly to the formation of adhesions.

Hormonal imbalances may play a role in reproduction but are not a primary factor in ectopic pregnancies. Genetic factors can influence various reproductive health issues, but they do not prominently contribute to the risk of ectopic pregnancy. Endometriosis can also lead to ectopic pregnancies but is more often associated with internal lesions rather than the external scarring that creates adhesions. Therefore, while some options might have relevance, adhesions stand out as the primary cause of ectopic pregnancies, emphasizing how previous damage or alteration in the reproductive tract can significantly impact pregnancy outcomes.