Anorectal complications of pregnancy: Anatomic and physiologic changes of the anorectum and pelvirectum during pregnancy

Abstract

1. 1. Anorectal disease in pregnancy is both directly and indirectly affected by specific anopelvirectal changes of pregnancy prenatally, with delivery and with changes of involution postpartum. 2. 2. The relationship of the anorectum and the pelvirectum is shown both anatomically and physiologically to the pelvis and genital organs in the non-pregnant state, during pregnancy and postpartum. This particularly relates to knowledge gained recently of their levator ani components from the levator ani structurely and functionally, and particularly relates to the profuseness of blood supply to the anopelvirectum with its profuse collateral blood supply throughout the pelvis. 3. 3. It has been shown that the work of Courtney on the anatomy of the pelvic diaphragm and anorectal musculature, now applied both anatomically and physiologically, demonstrates that the anorectum cannot be considered as an organ distinctly anorectal, but should be considered as an organ both pelvirectal as well as anorectal and as part of the levator ani. The levator ani assumes a vital part in the act of defecation as well as of childbirth which is anopelvirectal. Here pelvirectally is the area where a profuse blood supply to the rectum occurs. 4. 4. Specific anorectal and pelvirectal changes in pregnancy are outlined. 5. 5. Accompanying mechanical, hormonal and secretory changes affecting the gastrointestinal tract and directly or indirectly affecting specific anopelvirectal changes are outlined. 6. 6. Hemorrhoids and pruritus of anorectal and perigenital type have a high incidence during pregnancy. Other anorectal diseases have a low incidence. 7. 7. A new concept of the etiology of hemorrhoids and a new classification thereof is given. This is based on our knowledge of the profuse collateral blood supply in the pelvis to the ano rectum and pelvirectum and is also based on known accepted facts of the etiology and classification of varicose veins elsewhere than the anorectum. 8. 8. Anorectal disease in pregnancy, other than cancer, ulcerative colitis and postpartum communicating fistulas, such as rectovaginal fistula, are discussed in detail and new concepts of their presence or absence in pregnancy and their management as related to pregnancy changes, and to the pregnancy itself, are considered in each instance.