Quite literally, the menses is the period of waxing and waning between one new moon and the next. Once menstruation begins at puberty, which is a woman's first rite of passage, the ebbs and flows which her body goes through each month are the stuff of which the second movement in her life's hormonal symphony is made. This part of her life has one major goal - childbearing.
Its success depends greatly upon the two major steroids - the oestrogens and progesterone - working in close communication with her body's major control centers, the pituitary and hypothalamus.
Only since the late nineteenth century have women's menstrual cycles - the menses - been investigated scientifically. The name menses also comes from a Greek word - meaning `month'. It in turn is derived from an even older word meaning `moon'.
A neural nuclei in the limbic brain, the hypothalamus, is the control center for homeostasis. It balances and oversees biochemical and energetic changes throughout the body. The limbic system in which it sits is the most primitive part of the brain. It is the part which deals with emotions and with our sense of smell, with our passions, and with all the unconscious interfaces that take place between mind and body. The actions of the limbic lie beneath the level of the thinking mind. This is one of the reasons that the hypothalamus is often referred to as the `seat of emotions'. When excited, the hypothalamus triggers desire - for food, for water, for adventure, for sex. Its actions can also be influenced by inhibitory thought patterns. In a woman frightened of becoming pregnant, for instance, the fear itself - via the hypothalamus - can dampen sexual desire or even disrupt menstrual cycles so she remains barren. The hypothalamus also responds to alterations in the electric and magnetic fields of the earth and of moon, and to other planetary events, as well as to electromagnetic pollution in our environment and the positive stimulus of energy medicine. It reacts to bodily changes that take place as a result of meditation, and its activities are influenced by spiritual practices - which is a major reason why women who meditate regularly tend to develop greater emotional balance, as well as why repeated experiences of joy or stillness can dramatically improve various female complaints such as PMS and hot flushes in both menstruating and menopausal women.
There are three main branches of the female endocrine system involved in menstruation. The first is the master gland, the hypothalamus. It releases gonadotropin releasing hormone (GnRH). The second is the anterior pituitary, which releases follicle stimulating hormone (FSH) and luteinizing hormone (LH) - both of which are secreted in response to GnRH from the hypothalamus. The third is made up of the oestrogens and progesterone which, during a woman's non-pregnant childbearing years, are secreted by the ovaries in response to FSH and LH. It is the symphony of interactions and feedback mechanisms between these three branches that bring about the blood ritual of menstruation.
All of the hormones released during a menstrual cycle are secreted not in a constant, steady way, but at dramatically different rates during different parts of the 28 day period; a cycle which like everything else in a natural world involves birth, maturation, and death, only to lead to new birth again - in this case, of the egg a woman's body produces. Menstruation itself is simply the elimination of the thickened blood and blood filled endometrium in the womb - the lining developed in preparation for a possible pregnancy. For when a pregnancy does not occur, this lining is shed at monthly intervals under the control of oestrogen and progesterone with a little help from their friends GnRH, FSH, and LH. When ovaries are not stimulated by the gonadotrophic hormones from the pituitary, they remain asleep, as they were during childhood and as they become again after menopause.
For the first 8 to 11 days of the menstrual cycle, a woman's ovaries make lots of oestrogen. Within the ovary itself are little things called follicles - partially developed eggs. One of these will be released each month in hopes of meeting up with the sperm and creating an embryo. It is oestrogen which prepares the bloody lining of the uterus and causes the follicle to develop in the ovary, bringing it to the surface of the ovary and preparing for the release of one of the eggs. The word oestrogen, like the hormones produced in a woman's body which belong to this family - oestrone, oestradiol, and oestriol - comes from oestrus, a Greek word meaning `frenzy', `heat', or `fertility'. It is oestrogen which proliferates the changes that take place at puberty - the growth of breasts, the development of a girl's reproductive system, the reshaping of a woman's body. It also alters your vaginal secretions, making them more viscous and less watery, and it causes your body's temperature to rise at the time of ovulation, by about one degree.
Each girl baby is born with all the primary follicles she will ever need. At the time of puberty, a girl's ovaries contain about 300,000 of these follicles. And while each woman only produces one or two fully developed eggs each month, somewhere between 100 and 300 follicles have to start developing in order for one to become fully grown, so a woman can lose between 100 to 300 follicles a month. However, since she started with 300,000, she will have enough to last all her reproductive life.
On day one of each monthly cycle - that is, the day of the onset of menstruation - first the production of FSH and then of LH increases. This increase in hormones from the anterior pituitary triggers a group of ovarian follicles each month, causing accelerated growth in the cells surrounding them. As cells around the eggs grow, they secrete a follicular fluid which contains a high concentration of the oestrogen oestradiol to bring about many other changes, developing the potential of one of the follicles so that it becomes capable of being fertilized by the male sperm.
It is not the oestradiol alone secreted by the follicle which brings about the maturation of the egg, however. Luteinizing hormone (LH) from the anterior pituitary continues to be secreted to help the process along until after a week or more, when one of the follicles outgrows all of the rest. This is the one that will become the female egg ready for impregnation. The remainder of the follicles now begin to involute. LH becomes particularly important at this stage in order for the final follicular growth to be completed and ovulation itself to occur - that is, the release of the egg into the fallopian tubes for its journey down into the uterus. So the rate of secretion of LH by the anterior pituitary increases markedly, rising 6 or 10 times then peaking about 18 hours before ovulation - the release of the egg into the fallopian tubes for its journey down into the uterus. The production of FSH also increases at this time, and these two hormones act together to cause a swelling of the follicle during several days before ovulation. Finally ovulation takes place usually around the fourteenth day, in the middle of your cycle.
LH also alters the cells around the egg follicle, so that now they secrete less oestradiol, but progressively rising amounts of progesterone. This means that the rate of oestrogen secretion begins to fall about day thirteen, one day before ovulation occurs. But as small amounts of progesterone begin to be secreted, very rapid growth of the follicle takes place. Beginning with this secretion of progesterone, ovulation occurs too, triggered yet again by the luteinizing hormone from the anterior pituitary. During the first few hours after the ovum has been expelled from the follicle, more and more rapid physical and chemical changes take place to the egg in a process called luteinization. At this stage - known as the luteal stage of a woman's cycle - the follicle becomes known as the corpus luteum, or yellow body. The cells around the egg begin to secrete larger quantities of progesterone, as the level of oestrogen decreases. Some of the cells around the egg become much enlarged. They develop inclusions of lipids or fats which give them their distinctive yellow color. From now on, development becomes rapid until seven or eight days after ovulation, when it peaks.
As soon as a follicle releases an egg, the ovary switches over from pumping out oestrogen to primarily making progesterone. Progesterone is only synthesized when you ovulate. In fact, ovulation changes the whole ball game. No longer is there a need for further build up of the womb lining. The challenge now is to hold on to the secretory endometrium, and to render it capable of nurturing a fertilized egg long enough for it to grow into a baby. That is progesterone's task. The progesterone released with the egg has a negative effect on the other ovary. Its release tells the other ovary: "Hey, we've got an egg out now, so you don't have to worry about producing any." For even though women have two ovaries, they usually produce only one egg a month. The business of fraternal twins - that is, both ovaries releasing an egg at the same time - only happens once every three hundred months, which is why fraternal twins are so rare.
The corpus luteum, which forms each month, is a tiny organ with a huge capacity for hormone production. It releases large quantities of progesterone, plus some oestrogen, which cause a feedback decrease in the secretion of FSH and LH by the anterior pituitary, so that no new follicles begin to grow.
But as soon as the corpus luteum degenerates at the end of its 12 day life - which is about the 26th day of the female sexual cycle - this lack of feedback triggers the anterior pituitary gland to secrete several times as much FSH, followed a few days later by more LH as well. This in turn stimulates the growth of new follicles to begin the next ovarian cycle. And at the same time, a fall in progesterone and in oestrogen secretion trigger menstruation.
peaks and falls
From day 1 until about day 13 of a woman's menstrual cycle, the level of progesterone in her body is very, very low. Yet the point at which a follicle is released, it continues to rise dramatically until day 21 to 23, at which point it begins to fall down again to its lowest level, as menstruation begins around day 28. In addition to maintaining the endometrium and shifting down activity in the other ovary, the progesterone provided each month travels to other parts of a woman's body to fulfill other roles. It protects her from the side-effects of oestrogen for one thing, helping to protect her from getting breast cancer, from retaining water and salt, from high blood pressure, and from becoming depressed. Progesterone also brings surges of libido. You still hear a few so called experts say that oestrogen increases libido. But think about it. Which hormone would you rely on for sex-drive - oestrogen, which is present before the egg is made, or progesterone, which comes after the egg is released and is ready for fertilization? Libido increases with progesterone surges.
When this rhythmic cycling of oestrogen and progesterone during each lunar month gets out of sync (and many things in modern life can cause this) then all sorts of things can go wrong - from infertility to PMS, depression, bloating, endometriosis and fibroids. For the oestrogens and progesterone, each have their characteristic roles to play, and for a woman to be healthy they must balance each other.
the last and the first
So do all the other steroids: This group of hormones to which cortisol, aldosterone, progesterone, DHEA, testosterone and the oestrogens belong, is intimately involved in how you feel both physically and emotionally, as well as how rapidly your body ages. Steroids have a characteristic molecular structure which resembles cholesterol, from which they are all ultimately derived. Cholesterol is the vital fatty substance that has had such a bad press in recent years, but which is absolutely essential to life. Out of each steroid hormone made from cholesterol, yet another - and following that another - can be made in a knock-on effect. For instance, pregnenolone is the steroid manufactured directly from cholesterol. It in turn becomes a precursor to progesterone, as well as to other hormones.
Natural steroid hormones such as progesterone, made by biosynthesis in your own body, have this remarkable capability to act as precursors. In other words they are capable of being turned into other hormones further down the pathways as and when your body needs them. Progesterone is mother of many other hormones. It can eventually be turned not only into various oestrogens, but also into cortisol - the anti-inflammatory hormone - and into other steroids such as corticosterone or aldosterone, with equally important jobs to do. All of these conversions happen through slight alterations in the shape of a molecule, thanks to the actions of enzymes, each of which carries out a specific task. But these conversions can only take place if the molecules on which the enzyme is acting "fit" precisely - both electromagnetically and stereochemically - into its structure. All of these changes which take place through the magic of enzymes occur in the presence of vitamin and mineral cofactors such as magnesium, zinc, and B6, which catalyze each enzyme reaction. They are all carefully modulated by elaborate feedback mechanisms as well. The names and chemical transformations from one steroid to another are not important to remember. What is important is that you get some sense of just how complex hormone synthesis and interactions can be, and how important it is to have sufficient cofactors as well as `primary' hormones, such as pregnalone and progesterone, to be able to synthesize others. A rich hormonal symphony? Immeasurably. Yet all this still does not even begin to take into account the myriad pathways by which these steroid hormones interact with other hormones, or master central mechanisms within the hypothalamus and pituitary, or psychoneuroimmunological pathways by which hormones effect our emotions, and emotions our hormones.
It is in coming face to face with the rich textures of such hormonal symphonies that the synthetic progestagen drugs can come a cropper. When you look at the structures of their molecules, in every case you find that although they resemble your body's homemade hormones, their shapes have been altered slightly by adding extra atoms here or there at unusual positions. It is this that has enabled them to qualify as patentable drugs.
However, unlike the natural hormones - which they attempt to mimic, and which not only fulfill their own functions by binding with their own receptor sites but also act as precursors for a myriad of other hormones with other important jobs to do - the progestagens are end-product molecules. They are also completely foreign to the living body. Unlike nature's own steroids they can also not be augmented or diminished as necessary to maintain balance, and to keep the body's hormonal symphony flowing smoothly. They also cannot easily be eliminated when their levels get too high. Although the synthetics can still bind with the receptor sites of the hormones they are made to mimic, they don't fit as well as the homemade steroids do into the enzymes meant to act upon them. This means they are not under the watchful eye and control of these enzymes, nor of the body's self-regulating capacities. Drug-based oestrogens and progestagens in contraceptives and HRT cocktails can significantly disrupt a woman's normal hormonal cycles by introducing foreign elements into her body. They also virtually wipe out the moon cycles to which a woman's natural fertility and spiritual balance are inexorably bound from puberty onwards. So although in the short term they may temporarily do a job such as provide birth control or quell heavy bleeding in a menopausal woman, in the long run they only sabotage hormone balance, by turning harmony into dissonance - a dissonance capable not only of causing disruptions in a woman's health and physical body, but also of creating emotional and spiritual confusion in her life. This, sadly, is not something you will find described in the Merck index that warns doctors of a drug's side-effects, however. For the spiritual aspects of health and healing tend to be all but forgotten in the linear thinking that underlies most twentieth century medicine. In the mechanistic western world of drug-based treatments, where we are trained to take a pill for whatever ails us, this concept can be a little strange for some women to grasp. Especially if they are well educated, intelligent, and if they have been urged from puberty to rely on oral contraceptives - even told they are irresponsible if they don't. Or if they have been filled with fear that if they don't take HRT as menopause approaches their life is going to fall apart.
friends and lovers
Quite apart from their biochemical actions, rather like people, hormones have characters with highly individual personalities. To the biochemist, the `personalities' of the oestrogens and progesterone will always remain a mystery. He is interested in nothing beyond their molecular configurations. But many women come to know these personalities well - by allowing intuition and instinct to be their teachers. When progesterone is surging through the body, a woman can feel high. Provided her body is producing enough of this steroid, she is likely to feel great. Your senses are keen when progesterone is running. Smells smell sweeter - or more horrible. Touching, sensing, tasting, hearing, are all richer experiences than usual. In the presence of progesterone, women have a desire to do something, to create something, to work in the garden, to dance or sing a song, or make love. Sometimes progesterone surges can feel like falling in love. They can bring feelings of balanced wellbeing together with excitement - a desire to explore new worlds, and to try new things. This can happen during the luteal phase of the menstrual cycle after ovulation, when the follicle turns into the yellow body (or corpus luteum), but it becomes far more intense when you are pregnant. It is a high level of progesterone that makes a woman feel on top of the world during the last months of pregnancy. At this time the placenta churns out an amazing 300 to 400 milligrams of the steroid, while during the luteal phase of your menstrual cycle it will have only been producing 20 milligrams or so a day.
I suspect that among those women who seem to get pregnant over and over and who so love the whole experience, you are likely to find high progesterone levels. You also find them in women who have trouble-free menstruation. Sadly the opposite is true too: When progesterone is low - as it is in a growing number of women now, who have been subjected to manufactured hormones and who, living in the polluted world, have become oestrogen dominant - women never seem to feel well even during pregnancy. Many have all sorts of troubles with their female organs and cycles including PMS - sometimes from puberty right through to death.
when oestrogens flow
The oestrogens have quite a different character. When oestrogens peak in the menstrual cycle just before the `fall' of ovulation, a woman feels less independent. She is more willing to adjust herself to the needs of others. She is more inclined to see herself in relation to men too instead of as a woman in her own right. When the oestrogens are running, women like to attract a mate not so much to draw him into her body as to comfort, admire and care for her. Her ovaries seem to be smiling - `whatever you want, I'm happy to give', they seem to say. A few women who by nature are high oestrogen producers feel quite dependent on others for approval, and for the definition of their being. While such an experience can be lovely and make a woman feel highly `feminine', it can also go too far. However, in these women, when menopause finally arrives and oestrogen levels drop dramatically, often they find to their surprise and delight that for the first time in their lives they begin to feel complete in themselves - as though they don't need anybody else to validate their lives. Provided they are otherwise well, menopause can be sheer joy in the sense of freedom it brings these women - that is, once they get over the shock of being such a `different person'.
From a biological point of view, there are many important actions that progesterone and oestrogen exert upon the body and psyche. Since these are little known among women and doctors alike it is worth looking at a few:
Effects of Progesterone
Effects of Oestrogen
Prevents cancer of the womb
Increases risk of womb cancer
Protects against fibrocystic breast
Stimulates breast cell activity
Maintains the lining of the uterus
Proliferates the lining of the
Stimulates the building of new
Slows down the resorption of old
Is a natural diuretic
Encourages salt and water retention
Brings antidepressant effects
Can produce headaches and depression
Encourages fat burning
and the use of stored energy
Lays down fat stores
Normalizes blood clotting
Increases blood clotting
Concerned with the procreation and survival of the fetus
Concerned with the development
and release of the egg
Precursor to important stress hormones
The reproductive hormonal menstrual cycle of a woman between puberty and the menarche is a superbly ordered natural work of art. It becomes so much a part of our lives that unless we have some particular difficulties with PMS or fertility, we hardly give it any thought. Not, that is, until things begin to alter. Once they do begin - in most women sometime between the age of forty and fifty - they usually change gradually, until finally a woman senses that something deep in her being has shifted. Such feelings herald the coming of menopause - the third phase of a woman's life.