I'm not an expert, lol, but I do keep on top of the research. :) It just surprises me that all of these doctors and scientists cannot see all of the obvious holes in the theory upon closer inspection. It just isn't logical and prevents them from finding out what actually does cause endo.

The Problems With Sampson's Theory -
Is It A Theory Or An Excuse?

By David B. Redwine, MD

What is Sampson's Theory? The most popular and widely believed theory of origin of endometriosis, developed in the 1920's.

Who was Sampson? A bachelor gynecologist from Albany, New York.

What does it say? During menstruation each month, instead of all the menstrual blood flowing into the vagina, some of it goes in reverse and flows out the ends of the fallopian tubes. This menstrual blood carries with it some living cells from the lining of the uterus. These cells come to lie on the surfaces of the pelvis where they attach, implant, grow, and develop into endometriosis. An earlier version of the theory also postulated that endometriosis could occur by implantation resulting from rupture and spread of endometrioma cysts of the ovary.

Is there undeniable scientific proof supporting this theory?
No, and by now there should have been.

What does it predict?
Sampson's theory predicts that endometriosis will progressively spread throughout the pelvis with the passage of time, like dandelions seeding a field. More and more of the pelvic surfaces will be involved by the disease, and the recurrence rate after surgical removal will be 100%.

Is there undeniable scientific proof supporting this theory?
No, and by now there should have been.

The literature on Sampson's theory details a variety of circumstantial evidence seeming to support almost every step in Sampson's theory. Bloody peritoneal dialysate has been found during the menstrual flow in women undergoing peritoneal dialysis for kidney disease (although that study did not look for actual endometrial cells).

At laparoscopy performed during menstruation, bloody fluid has been seen coming from the end of the fallopian tubes (although when we insert a rigid rod inside the uterus to manipulate it, this can also induce some bleeding which can be forced out the fallopian tubes). Endometrial cells have been found in the fallopian tubes, peritoneal fluid and also in menstrual blood.

The endometrial cells which are found in menstrual blood are viable and can be cultured in the lab (although they grew in the subcutaneous tissue of autologous donors only 11% of the time). Sampson showed that if a hysterectomy was done during the menstrual flow, that if the surgeon chopped off the fallopian tube next to the uterus and squeezed the body of the uterus between his fingers, he could make blood come out the end of the severed tube.

The distribution of endometriosis in the pelvis has been offered as further evidence of Sampson's theory. It was argued that the ovaries were the most commonly involved pelvic area since they were closest to the ends of the fallopian tubes, so attachment and implantation of regurgitated endometrial cells should occur most commonly here first (although Sampson eventually figured out that the ovaries are not the most commonly involved area - the bottom of the pelvis is).

It was later postulated that the bottom of the pelvis is the most commonly involved area due to the effects of gravity pulling viable endometrial cells down to the cul-de-sac (so Sampson's theory can mutate to accommodate the available information).

It has been suggested that endometriosis is a progressively spreading disease due to this continued seeding (although pelvic mapping studies have not found a greater distribution of disease in older age groups of untreated patients). It has been argued that the 100% recurrence rate after surgery is simply due to the fact that the pelvis gets re-seeded monthly after surgery (although the published recurrence rates after excision are much lower than this) and the high 'recurrence ' rate may simply be persistence of disease which was not destroyed by superficial laser vaporization or electrocoagulation or by medical therapy.

Joe Meigs, a prominent gynecologist of the mid-century, wrote in 1953 that endometriosis could be cured by conservative surgery (that's right, he used the 'c' word).

If you don't look too deeply or too critically at Sampson's theory and ignore the words in the parentheses above, it looks pretty perfect. If only the reality that women with endometriosis experience would match the theory, life would be perfect. It doesn't. Life is imperfect because the theory is wrong, and there is undeniable scientific proof that it is wrong.

To understand the flaw of Sampson's theory, all you have to do is visualize a pine forest. When you walk across the forest floor, what is that crunching sound under your feet? It is the sound of pine cones under your shoes. As you look at the forest floor, you can see the pine cones attached by gravity to the surface of the ground. You may also see some pine seedlings and younger trees among the mature trees.

Now let's look at the pelvic floor. Sampson's theory predicts that individual endometrial cells should be attached to the surfaces of the pelvic floor in fairly large numbers. These cells are not small and should easily be seen with a light microscope. It should be absolutely easy to find these attached cells; one could almost take random biopsies blindfolded and expect to find them under the microscope. By now, textbooks should be filled with photomicrographs of dozens or hundreds of examples of these attached cells.

Furthermore, there should be similar abundant evidence of the progressive invasion of these attached cells into the pelvic surfaces, followed by the evolution of these cells into endometriosis. This continuum of the earliest attachment of endometrial cells changing into endometriosis should be easy information to come by and to be proved by photography. This pictorial evidence should introduce every discussion of Sampson's theory in every textbook, yet it doesn't because there is no such abundant evidence available.

The Problems With Sampson's Theory -
Is It A Theory Or An Excuse?

The concept of initial attachment could be viewed as the "Holy Grail" of endometriosis. Find it and you might prove Sampson's theory and convince skeptics like me that it is true. But it should have been found long before now. Those who have studied microscopic endometriosis have not found evidence of initial attachment. There are only two possible reasons for the continuing lack of evidence of initial attachment:

Those favoring Sampson's theory have not looked for it.
Initial attachment does not occur because Sampson's theory is incorrect.

Sampson's theory leads to a sense of hopelessness among patients and physicians alike. But this is about more than just scientific uncertainty concerning the origin of a disease. This sense of futility can have a direct effect on surgical treatment of the disease.

If a surgeon is convinced that the disease will "just come back" after surgery, (s)he may not try as hard to get all of the disease out, resulting in persistent disease which is its own self-fulfilling prophecy of "recurrence."

If a surgeon burns only the top of endometriosis with laser or electrocoagulation, but believes that all of the disease has been destroyed, persistent disease can be blamed as "recurrence" due to Sampson's theory.

Medical therapy can be similarly influenced. Although no one has ever bothered to do a study proving that pregnancy or menopause eradicate endometriosis, all medical therapy is based on duplicating the assumed beneficial effects of these two hormonal states. We know that medical therapy does not eradicate the disease, but if a physician believes that it does, then "recurrence" after medical therapy can also be blamed on Sampson's theory. How much more perfect could this be?

With Sampson's theory as a foundation, failure of medical or surgical therapy is never due to ineffectiveness of the medicine or the surgery, it's due to the fact that the pelvis is re-seeded again next month, and the month after. It's not the fault of the system, it's the nature of the disease.

Physicians don't have to be introspective about their treatment methods, since failure is explained and predicted, and it's not their fault. In my view, Sampson's theory is actually Sampson's excuse for our time.

In all of this discussion, I am not blaming John Sampson for anything, and I don't want people to think I am disrespectful of him. He was an excellent student of endometriosis, and he did the best he could in developing his theory of origin with the evidence of the time. If he knew what we now know about endometriosis, I'm certain he would not have arrived at the same theory.

The problem lies in the human trait of accepting things from the past without question, and this continues to be our problem today. We need more healthy questioning of authority.

In the next issue, I'll explain what my 17 years of study have led me to believe about the origin of endometriosis. So Where Does Endometriosis Come From?

What causes it?

The simple answer is, we don't know for sure. However, there are several theories:

Sampson's Theory

The oldest and most widely taught theory is that menstrual blood sometimes flows backwards into the pelvis. That is, instead of draining out of the body through the vagina, the theory holds that the menstrual fluid backs up the fallopian tubes and drips into the pelvis, where it attaches to any surface and establishes a blood supply. If Sampson's theory is correct, endometriosis is not possible until a girl's first period occurs.

Metaplasia Theory

In the embryo, cells with the potential to mature multiple ways develop in the wrong way in the wrong location. These misplaced cells are present at birth.

Congenital Theory

In the embryo, cells that are intended to form the uterus get left out when the uterus closes before they arrive. The leftover cells are generally found along the coelomic ridge, and are present at birth.

Vascular Theory

This theory holds that the lining of the uterus (the endometrium) moves through the body via blood vessels. It reaches various tissues and then implants and survives.
What does Dr. Albee believe?

I believe that multiple etiologies exist. That is, more than one theory may prove to be correct.

When we see endometriosis in an abdominal scar after a cesarean section, we must invoke a theory that includes transplantation. Also, certain research with primates shows that when the animal's cervix is blocked so menstrual fluid can't escape, endometriosis inevitably develops. These instances seem to add weight to Sampson's theory that retrograde menstruation leads to endometriosis.

However, it is estimated that more than 70% of all women experience some degree of retrograde menstruation, but only 12-15% of women have endometriosis. How do we account for the other 55%?

Also, when I review a woman's videotapes of multiple previous surgeries, I rarely see disease in a new area. That is, for example, if bladder disease is present at surgery A, it may persist through subsequent operations (if it was not completely removed). On the other hand, if bladder disease is not present at surgery A, it does not suddenly appear at surgeries B, C, D, etc. If Sampson's theory of retrograde menstruation is correct, it is reasonable to expect to see new disease in new areas. But, in my experience, this does not happen.

It has been my experience with hundreds of cases that, if all a woman's endometriosis is completely removed at surgery, she has better than an 90% chance that it will not recur. This evidence favors a metaplastic or congenital theory because it suggests endometriosis is a finite disease. That is, a woman has as much as she has (whether a little or a lot) and that if it is completely excised, it will not grow back.

Other points that contradict Sampson's theory are that endometriosis has been found at autopsy of infants, who clearly have not ever menstruated. Also, because most of the menstrual flow involves the vagina and vulva, a logical extension of Sampson's theory would predict a high incidence of endometriosis in those locations. In fact, vaginal and vulvar endometriosis are rare.

Evidence of endometriosis in spots far from the pelvis (such as the brain and lung) suggests either a metaplastic theory or implantation by vascular spread.

All in all, there is no denying that transplantation can be a source for endometriosis. My concern is the leap of faith taken when we allow that idea to foster the assumption that endometriosis can never be cured. A meticulous approach to surgery, and totally excising every visibly abnormal area of peritoneum seems to result in long-term symptom relief in more than 90% of all patients.

Barbie, remind me why you don't want to try the bioidentical progesterone cream at night?Oral progestin is the drug that gave more women breast cancer when taken with premarin during the WHI study and the women without wombs who only took premarin got less breast cancer.That's another subject but still points to the danger of synthetic progestin.

Maybe all progestins are not created equal. The progestin in the WHI study was Medroxyprogesterone(Provera), which acts like cortisol, so may contribute to weight gain. Other progestins, for example norethindrone haven't been studied in the same way(I don't believe), so risk may be speculative. I personally liked norethindrone when I used to take it as part of a birth control pill.
Sue