What causes an ectopic pregnancy?

Ectopic pregnancy refers to a pregnancy that occurs outside the uterine cavity. Ectopic pregnancy can be caused by various factors:

1. Salpingitis: Chronic salpingitis is a significant factor leading to ectopic pregnancy. Inflammation can cause adhesion of the fallopian tube mucosa and narrowing of the tubal lumen, hindering the normal passage of the fertilized egg through the fallopian tube into the uterus, thereby causing ectopic pregnancy.
2. History of tubal surgery: Previous tubal surgeries, such as tubal anastomosis or adhesiolysis, may affect the structure and function of the fallopian tubes postoperatively, resulting in ectopic pregnancy.
3. Contraceptive failure: When using intrauterine devices (IUDs) for contraception, although implantation of the fertilized egg within the uterus can be prevented, the risk of ectopic pregnancy may increase.
4. Poor tubal development or functional abnormalities: Some women are born with abnormally long, narrow, or curved fallopian tubes, which may interfere with the normal transport of the fertilized egg through the fallopian tubes, leading to ectopic pregnancy.
5. Abnormal migration of the fertilized egg: If the fertilized egg does not travel through the fallopian tube after fertilization but instead reaches the fallopian tube via the abdominal cavity, it may result in ectopic pregnancy.

When symptoms suggestive of ectopic pregnancy occur, prompt medical attention and comprehensive evaluation are necessary to determine the underlying cause and implement targeted treatment.