What are the causes of ovarian cysts?

What are the causes of ovarian cysts?

There are three theories about how ovarian cysts are formed:

1. Endometrial implantation theory: It was first proposed that endometrial fragments shed during menstruation enter the abdominal cavity through the fallopian tubes with retrograde menstrual blood, implant in the ovaries and adjacent pelvic peritoneum, and then grow and spread, developing into endometriosis. Women with reproductive tract malformations or obstructions often have complications of endometriosis, indicating that retrograde menstrual blood can cause endometrial implantation.

Repeated or overly rough gynecological bimanual examinations squeeze the endometrium into the fallopian tubes, causing abdominal implants. Improper operating procedures for ventilation, fluid perfusion, and imaging of fallopian tube patency tests can press endometrial fragments into the abdominal cavity through the fallopian tubes, causing abdominal implants. Endometriosis in abdominal wall incisions or perineal wounds after childbirth is caused by the surgeon bringing the endometrium to the incision, resulting in iatrogenic implants. Endometrial implants are caused by the contents of the uterine cavity overflowing into the abdominal cavity during cesarean sections and cesarean sections, and when suturing the uterine incision, the sutures pass through the endometrial layer, etc.

2. Lymphatic and venous spread theory: The presence of endometrial tissue in the pelvic veins or lymph nodes supports this theory. It is also believed that endometriosis occurring in organs far away from the pelvic cavity, such as the lungs, hands, skin and muscles of the thighs, may be the result of lymphatic or venous spread.

3. Coelomic metaplasia theory: The female reproductive system epithelium, ovarian reproductive epithelium and pelvic peritoneal pleura all originate from the coelomic epithelium. When affected by factors such as inflammation, trauma, and excessive estrogen, or when the coelomic epithelium is repeatedly stimulated by menstrual blood, hormones, or chronic inflammation, it can metaplasia into endometrial-like tissue and form endometriosis.

80% of endometriosis occurs in the ovaries, which is related to the metaplastic potential of the ovarian germinal epithelium. However, many scholars currently believe that peritoneal irritation combined with endometriosis is the result rather than the cause, and peritoneal irritation occurs in areas other than ectopic foci.