| Gynecologic |
| Endometriosis |
| Adenomyosis |
| Fibroids |
| Ovarian cysts |
| Intrauterine or pelvic adhesions |
| Chronic pelvic inflammatory disease |
| Obstructive endometrial polyps |
| Congenital obstructive müllerian malformations |
| Cervical stenosis |
| Use of an intrauterine contraceptive device |
| Pelvic congestion syndrome |
| Hematometra |
| Nongynecologic |
| Inflammatory bowel disease |
| Irritable bowel syndrome |
| Uteropelvic junction obstruction |
| Psychogenic disorders |
