Menopause is a normal biological process that typically affects women around the age of 50. During menopause, a woman stops ovulating and menstrual periods gradually come to an end, which means she can no longer get pregnant. The process is due to hormonal changes in the body, namely variations in estrogen, progesterone, and follicle stimulating hormone (FSH) production. During and after menopause, FSH levels in the body are very high and estrogen levels are low. The connection between menopause and FSH is well-established, and doctors often test FSH levels in order to determine when a patient enters and completes the menopause cycle.
FSH is produced by the pituitary gland and transported to the ovaries. When hormones reach the reproductive tract, they stimulate the growth of new ovarian follicles to begin the ovulation process. Mature follicles secrete estrogen which regulates the rest of the menstrual cycle. In women of reproductive age, FSH levels rise until ovulation begins, then drop sharply after an egg is released.
In the case of impending menopause, FSH levels remain high throughout a woman's menstrual cycle. The reason is that follicles stop producing adequate amounts of estrogen. The pituitary gland senses low estrogen levels and reacts as if ovulation has not yet begun by releasing more FSH. The ovaries stop producing enough estrogen for ovulation after menopause and FSH levels remain elevated. The pituitary gland continues to release more and more FSH to jump start estrogen secretion, but to no avail.
Many physicians rely on the connection between menopause and FSH to trace the different stages of the process. Urine samples are collected and analyzed in a specialized laboratory to detect a patient's FSH levels on certain days. When a woman is still having periods, FSH is tested on the third day of menstruation when levels are expected to peak. If readings are higher than suspected, it may be a sign that menopause is near. After periods start becoming less frequent or irregular, FSH readings tend to be consistently high.
For various reasons, some younger women experience early menopause and FSH increases. FSH tests are vital in determining if infertility, irregular periods, and other symptoms are related to early menopause or another health problem such as ovarian cancer. As the connection between menopause and FSH becomes better understood by doctors and researchers, new medications and hormone replacement therapy techniques may be able to help younger women once again establish normal reproductive characteristics.