Menstrual cycle

Control of a woman’s menstrual cycle originates in a part of the brain known as the pituitary gland. This produces two hormones which act on the female reproductive organs to perform two main tasks:

• They cause the ovaries to produce and secrete an egg each month.
• They thicken the lining of the uterus, preparing it to feed the fertilized egg.

At a certain time of the month, an egg is released from the ovaries—this is known as ovulation. The egg then travels into the uterus where it looks for a handsome sperm hoping to be fertilized. When this happens, the fertilized egg embeds itself into the prepared uterine lining, to be nurtured by the womb. This will be the start of a new life.

However, if the egg is not fertilized after a few days, it dies. The thickened lining of the uterus is then unnecessary, so it starts to disintegrate and is shed from the uterus approximately 14 days after ovulation. This is what a woman will experience as her period, or menstruation.

The lining of the uterus then goes through the cycle again, producing a fresh layer of cells in the hope of receiving a fertilized egg the following month.

As a woman approaches menopause , it is not uncommon for the menstrual cycle to become irregular or for menstrual bleeding to be heavier. These symptoms can be experienced up to a few years before periods finally stop and is known as perimenopause .

As a woman ages, childbearing becomes more risky for both mother and child, and nature has a way of telling the body that it is not as fit as it once was, especially for the important task of carrying a child.

Production of the pituitary hormones declines and becomes erratic, leading to irregular periods. The ovaries become less responsive and they eventually stop releasing eggs. The regular thickening of the uterine lining becomes redundant and, with a reduction of both estrogen and progesterone, periods stop.

In this way, menopause signals the end of a woman’s reproductive career!

The decline in hormone levels during menopause and the perimenopausal period can give rise to a variety of symptoms, including hot flashes and night sweats.