It is interesting to me that many older physicians, and other medical providers (nurses), seem to disagree regarding enema use. I have read a plethora of text entries, news articles, and other literature where there is obvious disagreement amongst the “experts”.
In Google Books, it is possible to find texts, newspaper articles, and columns penned by physicians who regularly wrote about enema use, and answered questions posed by readers. Many of these were from decades past. In the Wayback Machine, the same is true if one searches for text regarding enemas.
Opinions are quite diverse, and one thing is certain, enemas have been around for centuries. Some believe they were merely a fad, while others believe there was a legitimate use for a variety of circumstances including medical conditions as well as vanity concerns.
Most physicians are loathe in considering self diagnosis on the part of their patients. They seem to want to be able to consult on many factors and discourage many of those self prescribed treatments or OTC attempts to treat a variety of conditions. In reality, they usually won't prescribe tests, xrays, treatments, or meds without a more “hands on” appointment. The tough part is that appointments are often weeks or months in the future.
As one who has had a so-called enema “habit”, "dependency", “addiction”, “fetish”, or “paraphilia” since childhood, I don't believe my health has been compromised due to my frequent use of this simple procedure or pleasure. As others indicate, and I agree, my digestive system returns to it's normal/natural tendencies within hours depending on my food intake as well.
I believe I am somewhat cautious in using fairly typical equipment that is appropriately cleaned and cared for. I do enjoy some oversized nozzles that tickle my prostate or deliver solution higher into my colon. The volumes I use, would never put me into contention with the winners of capacity contests. My personal preference is to use a reasonable volume of solution in lieu of laxatives, stool softeners, or other OTC or prescribed drugs. When a top down cleanse is required for a medical procedure, I will adhere to directions, but supplement with enemas to assure an adequate cleanse.
As far as the increasing volumes, whether by mom, grandma, nurse, or doctor, I would assume that they likely were prescribed, and endured some fairly large volume enemas prior to childbirth, barium enema, or preparation prior to surgery. That's how it was back in “the golden era”. It seems sensible to assume that because they were subjected to large volumes (HHH), they found it appropriate, or even advisable, to up the ante with us kids at home. A small volume may empty the rectum, but a larger volume might just empty the entire system, overcoming the need to use multiple enemas on a resistant brat of a kid. Perhaps there was a bit of a punitive streak because we kids had failed to maintain regularity or ate something that created a digestive problem. In a few instances, a large soapy enema was possibly meant for some type of behavior modification.