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Articles on Menstruation

Endometriosis  Based on research of John R. Lee, M.D.

Endometriosis is a painful condition in which fragments of endometrial tissue are present in areas where they do not belong: the fallopian tubes, uterine musculature (adenomyosis), and often on the outer surface of the uterus and other pelvic organs, the colon, the bladder, and the sides of the pelvic cavity. With each monthly cycle, the endometrial fragments respond to ovarian hormones by building up the endometrial tissue within the uterus. They increase in size, swell with blood, and bleed into the surrounding tissue at menstruation. The bleeding accumulates into the pelvic cavity, forms cysts and exerts pressure. The surrounding tissue becomes inflamed and very painful. Symptoms begin 7 to 12 days before menstruation and then can become excruciatingly painful during menstruation. The pain may be diffuse depending on the sites involved. Diagnosis is not easily established as there is no lab test to identify endometrial fragments nor are they large enough to show on an X-ray or sonogram. Laproscopy is useful because it enables a doctor to look into the abdomen with a small scope.

The cause of endometriosis is unclear. Some argue that endometrial cells wander through the fallopian tubes while others suggest they are displaced through an embryological mix-up when an embryo is just forming its tissues. The fact is, endometriosis seems to be a disease of the 20th century. Now that we know about xenoestrogens and the fact that the tissues of the developing embryo are especially sensitive to the toxic effects of xenoestrogens. It may be that endometriosis is related to an estrogen dominant situation in the body.

Direct Quote from Dr. Lee

"This treatment requires patience. Over time (four to six months), however, the monthly, the monthly pains gradually subside as monthly bleeding in the islets becomes less and healing of the inflammatory sites occurs. The monthly discomfort may not disappear entirely but becomes more tolerable."

Treatment of endometriosis is difficult. Surgical attempts at removing each endometrial implant are only temporarily successful because many of the fragments are too small to see, and eventually they can enlarge and the condition recurs. Other surgical options that aim to remove or reduce hormone levels include: the removal of ovaries, the uterus and the fallopian tubes, drastic measures according to Dr. Lee.

Pregnancy often retards endometriosis and occasionally cures it. With this in mind, other medical treatments attempt to create a state of pseudopregnancy. Physicians often prescribe a long period of supplemented progestins to simulate the high progesterone levels of pregnancy. Unfortunately, the high doses are often accompanied by side effects of the progestin and breakthrough bleeding. Also, progestins are synthetic and have a host of negative side effects, including breast cancer.

Natural Progesterone & Endometriosis

Dr. Lee treated a number of endometriosis patient with natural progesterone and observed considerable success. Since estrogen initiates endometrial cell proliferation, natural progesterone blocks the monthly estrogen stimulus to the abnormal endometrial fragments and can stop further proliferation of endometrial cells.

Dr. Lee recommended women use natural progesterone cream from day 6 - 26 of the cycle each month. This treatment requires patience and over time the monthly pains can gradually subside as monthly bleeding become less and healing of the inflammatory sites occur. According to Dr. Lee, many women successfully alleviate the pain and suffering of endometriosis through the use of natural progesterone.

According to Dr. Lee in his book, The Multiple Roles of A Remarkable Hormone, over time, most patients find reduction of pain in 3-4 months and continued relief as time goes by. When endometriosis pains have subsided, the dose can be reduced gradually to find the level that keeps the pains away. Endometriosis is cured by menopause, when estrogen levels decline. It was a mystery to Dr. Lee why synthetic progestins are recommended when the natural progesterone is available, cheaper, and safer.


Bowman, K. et al. “The Influence of Progesterone and Androgens on the Growth of Endometrial Carcinoma.” Cancer 71(11) (June 1, 1993): 3565-3569.

Gompel, A., J. C. Sabourin, A. Martin, H. Yaneva et al. “Bcl-2 Expression in Normal Endometrium during the Menstrual Cycle.” American Journal of Pathology 144 (1994).: 1196-1202.

Gruenigen, V.E., and J. R. Karlen. 1995. Carcinoma of the endometrium. American Family Physician, May 1:1531-36.