| Hormones before menopause work on a cycle | | | | produces heaps of progesterone but only in the |
| controlled by the pituitary gland just underneath the | | | | second half of the cycle, so as to ensure that the |
| very centre of the lower surface of the brain. This | | | | new embryo, if present, has the best possible chance |
| little gland is the 'conductor' of the orchestra of | | | | of being properly embedded in the uterine wall and |
| endocrine glands in the body, including the thyroid, | | | | the woman's early pregnancy proceeds without |
| the adrenals, and the ovaries or testes. | | | | problems. A low progesterone output during the |
| The pituitary is organised on a bio-rhythm sort of | | | | second half of the ovarian cycle will often indicate an |
| cycle, some say related to the phases of the moon. | | | | inability to carry a fertilised egg into later pregnancy. |
| There is good evidence to show that this may well | | | | The IVF clinics around the world, and also in Australia |
| be true! It also responds to what is going on in the | | | | where it all began, will give their patient progesterone |
| brain, at least to some extent. The brain is the | | | | routinely to ensure the best possible environment for |
| 'commander in chief'. If there is some sort of huge | | | | the fertilised egg. |
| trauma going on, a big shock or critical performance | | | | So if you only have progesterone after ovulation, |
| issues such as chronic long distance running or long | | | | then a pre-menopausal woman only need |
| term starvation, the hypothalamus part of the brain, | | | | progesterone from Day 10 or 12 to the next period. |
| which lies geographically above the pituitary, can | | | | But it is different in menopause. The whole hormone |
| communicate with the little gland almost | | | | orchestra changes because of the slow, or no, |
| instantaneously to affect its output. | | | | ovarian response to FSH. The pituitary continues to |
| Before menopause in a normal woman, the pituitary | | | | try to stimulate the sluggish ovaries, and puts out |
| puts out FSH or Follicle Stimulating Hormone to | | | | increasing amounts of FSH, which can go up to |
| stimulate the ovaries to develop and then release an | | | | 300-350 before the pituitary recognises that there is |
| ovum or egg for fertilisation. Since the reproduction | | | | never going to be any response from the ovaries, |
| of the species depends on this cycle of FSH and | | | | and it slowly reduces the amount of FSH. |
| ovarian response, it takes a major impact of some | | | | Slight or absent ovarian response also means there is |
| sort to disturb the pituitary so that it stops | | | | less oestrogen running around the blood stream. The |
| stimulating the ovaries. But under normal | | | | combination of high FSH + low oestrogen (not merely |
| circumstances the FSH during the fertile years runs at | | | | low oestrogen alone) is what causes the hot flushes. |
| anything from 3 to 30 or thereabouts. | | | | We know this because when the FSH reduces back |
| So, what about progesterone, the 'forgotten' | | | | down, even when there is less than 10 units of |
| hormone? | | | | oestrogen, there is no hot flushing! At that point the |
| Well progesterone is produced in the ovary after the | | | | woman has successfully traversed the menopause |
| egg has been released for fertilisation. The body | | | | and is now post-menopausal. |