Mapping the cycle

Throughout a woman’s reproductive life, the ovaries control her menstrual cycles. They produce varying levels of oestrogen and progesterone throughout the month, (most women have a 28-day cycle), that prime the woman’s uterus for implantation of a fertilised egg – pregnancy.

Here is a brief description of what occurs through her cycle:

Day one of her menstrual bleed is day one of her cycle. On this first day of her cycle, her oestrogen and progesterone levels are at their lowest. They remain low for the first half of the cycle. Around the middle of the cycle, around day 12 to 14, the ovaries produce an oestrogen surge that is dramatic but is short lived. This is for ovulation to occur. Once ovulation has occurred, the oestrogen returns to the low level and then progressively increases over the next two weeks right up until just before her next period. The rising oestrogen stimulates the endometrial lining of the uterus, priming it for implantation of a fertilised egg. If implantation does not occur, the endometrium breaks down (a menstrual bleed) and the oestrogen drops again to its lowest level. Throughout the cycle, the ovaries will be producing enough progesterone to balance this oestrogen.

Progesterone and oestrogen balance with each other. This prevents either hormone dominating over the other. If one hormone does dominate, the patient starts to experience symptoms of this dominance.

As a woman enters early menopause, these levels of oestrogen and progesterone both drop, but at different rates, so that an imbalance of oestrogen relative to progesterone results. Both hormones are still changing through the cycle but at lower levels and at different rates of change. Symptoms start to appear that reflect both the lower hormones and the imbalance of the two hormones. Eventually she stops menstruating and there is confusion as to where she is in her cycle.

Many of the early symptoms of menopause reflect these changes: overheating, irritability, weight gain, breast tenderness, headaches. The symptoms come and go through the month and, in fact, reflect the cyclical changes that are still occurring, even in the absence of a period. And the higher oestrogen level relative to progesterone at different points in the cycle is what brings about the changing symptoms, both in their character and their severity.

At the Australian Menopause Centre we have developed a method of determining these changes in hormones and we are able to map out your cycle when things have become too confusing. This allows us to target your symptoms more accurately with the correct treatment and its dosage. The process involves having four weekly blood tests which we compare with a calendar of symptoms that you will provide during the month of blood testing. By combining the symptom calendar with the weekly blood test, we can map out your ongoing cycle, enabling us to better customise your treatment for your needs. By having a treatment that is more specific to you, you can avoid the potential for fluid retention, weight gain, breast tenderness and even break through bleeding.

Written by Dr Gary Aaron