right place at the right time, to enhance the reproductive and immune systems. The correct choice of food will help our bodies to work efficiently as the nutrients help to trigger the correct hormonal messages.
CERVICAL MUCUS
The uterus is connected to the vagina through a small opening called the cervix, which acts as a physical barrier to protect the female reproductive organs from germs in the external environment. The state of the cervical mucus within the vagina is very important in achieving fertilization, and is also dependent on the correct hormonal messages.
Oestrogen makes the mucus runny and slippery, like egg white, making it easy for the sperm to swim through it and for conception to take place, rather like a superhighway for sperm. By watching for a clear mucus coming from the vagina, you will have a good indication as to when ovulation takes place. Mid-cycle (at ovulation) cervical fluid is copious and watery, and secreted at a rate of 600mg per day. It contains salts, amino acids, proteins, peptides and lipids.17
Progesterone, on the other hand, reduces the secretion rate to 20–60mg per day and thickens the mucus to stop sperm or bacteria from entering the womb during the second half of the cycle, when the uterus could contain a pregnancy that needs protection from the external environment. (See Appendix D, for natural fertility guidance.)
ENDOMETRIOSIS
ENDOMETRIUM VERSUS ENDOMETRIOTIC IMPLANTS
The endometrium of the womb plays a vital role in the reproductive process. It is a dynamic tissue that undergoes continuous changes in the preparation for and maintenance of pregnancy. But although the endometrium is required for normal reproduction, it is also the major culprit in endometriosis. In this disease, pieces of endometrium grow and develop in areas outside the uterus. These rogue pieces of the normal endometrium are called ‘endometriotic implants’ by gynaecologists and scientists, and they can be found throughout the body. In general, however, endometriotic implants are usually found in the lower abdomen with the greatest number occurring in the base of the pelvis or the cul-de-sac/Pouch of Douglas and on the outer surface of the womb, ovary and the bowel, bladder and intestines (figure 2.5).
To a lesser extent endometriotic implants are found in the upper parts of the abdomen, including the small intestine, stomach, liver, gall bladder, kidney, pancreas and diaphragm, and also in the vagina and on the external genitalia. Implants have also been noted in lungs, skin spots, joints, the brain, gums and in the lining of the nose, but these locations are, thank goodness, fairly rare. They have even been observed in the scar tissue in women who have had hysterectomies or Caesarean sections. A bizarre location for endometriotic implants is in the joints of elderly men.18 Three men in Australia were found to have endometriotic implants on their bladder as a result of taking oestrogenic drugs for cancer of the prostate.19, 20 As men do not have a uterus, this is a true medical curiosity. Some scientists believe that we are born with a potential to develop endometriosis because, as a fetus develops, some of the endometrial cells migrate to the wrong place and are triggered by a hormonal message at some later date. Endometriosis is so curious and very difficult to live with, but fascinating in its bizarre behaviour.
WHAT CAUSES ENDOMETRIOSIS?
Although we do not have definitive proof of the true origin of this disease, several theories have been proposed as to what causes endometriosis. Dr Sampson in the early 1920s developed the theory of ‘retrograde menstruation’.21 He reported that endometrial tissues, in addition to flowing out of the vagina at the time of menstruation, also move up into the Fallopian tubes, from where they pour into the peritoneal cavity (abdomen). These backward-flowing fragments of endometrium then attach to the cells lining the abdomen and grow in a similar fashion to the uterine endometrium.
Sampson’s theory has received the most support from the scientific community, since it agrees with the observation that the numbers of endometriotic implants increase with proximity to the opening of the Fallopian tube. As the endometriotic tissue flows out of the tubes, it would bathe the outer surface of the ovary and uterus, and large amounts would settle at the base of the pelvis in the cul-de-sac/Pouch of Douglas area. As mentioned above, these are the areas of highest occurrence of the disease. Recent research by Dr Jouko Halme of North Carolina University, USA, also supports Sampson’s theory. Dr Halme examined the abdomen of his patients at the time of their menstrual flow. He observed the presence of endometrial fragments in the peritoneal (abdominal) fluid of 90 per cent of those who had normal, open tubes, compared with no endometrial fragments in the peritoneal cavity of the patients who had their tubes tied.22
These studies confirm that endometrial tissue can make its way through the tubes into the abdomen. Research performed by Dr Michael Vernon on monkeys has also shown that endometrial tissue placed on the surface of the cells lining the abdomen readily supports the growth and development of endometriotic implants.23
Thus it seems that Sampson’s theory of retrograde menstruation provides a workable explanation of how endometriosis starts. However, it does not explain how endometriosis can develop in the bladder of men, so some additional theories have been suggested over the past 60 years. A second theory proposes that endometrial fragments work their way into the blood circulation or lymphatic system at the time of the menstrual period. The uterus has a rich supply of blood and lymphatic vessels (see figure 9.1). As the endometrium is sloughed off, some pieces may enter open blood vessels or the lymphatic system and travel around the body. The lymphatic system is a part of the immune system and is explained in detail in chapter 9. It is similar to the blood circulation system, except that there is no heart to act as a pump. The body’s movements aid the flow of the lymph, which is an oil-like fluid through which the white blood cells can flow. This theory offers an explanation for endometriosis in lungs, since endometrial fragments entering the circulatory system at the uterus would flow freely until they reach the small blood vessels in the lungs. It also may explain the presence of endometriosis in joints.
Figure 2.5
Cross-section of the female torso showing the areas of the body where endometriosis is most frequently found.
Another theory, noted by Meyer in 1927, proposed that epithelial tissue (the cells on the surface of most tissues) has the ability to transform into different types of epithelial tissue. Meyer proposed that some epithelial tissue (for example, joint epithelial cells) is converted into endometrial cells, thus explaining how men may develop endometriosis.24 Quite perplexing, isn’t it? The important question is ‘Why does this happen in some women, but not in others?’ Once we can find the answer to this, we will be nearer the cure. It is felt that a healthy immune system is the key to the removal of the endometriotic implants.
As the endometriotic implants are composed of a tissue very like that of the endometrium, the implants behave like the endometrium, and they respond to the same endocrine hormone messages. In fact, when Sampson first described the disease in the 1920s, endometriotic implants were sometimes referred to as ‘mini-uteri’. Using microscopic observations, Dr Deborah Metzger of Yale University has closely examined the response of the endometriotic implant to ovarian hormones. She noted ‘a correlation between morphological features (physical appearance) and the ability of endometriotic implants to respond to endogenous gonadal hormones (oestrogen and progesterone) in a manner similar to intrauterine endometrium’.25 So the two tissues behave in an almost identical manner, one having a life-giving function and the other causing misery and pain.
Women with endometriosis in their noses actually have nosebleeds at the same time as their menstrual period. When the oestrogen of the ovary stimulates the cells of the uterine endometrium to proliferate, the cells of the endometriotic implant also increase. Therefore, endometriosis may ‘spread’ in response to the oestrogen produced during the menstrual cycle.
It has also been suggested that endometriotic implants may be fuelling their own growth by producing