A normal cycle occurs every 25-34 days. Most women have between 9-13 periods a year. With irregular cycles the time in between varies considerably. There are many reasons . The most commonly seen in my practice are listed below.
Certain methods of birth control such as an IUD or changing birth control tablets.
These can lead to irregular cycles or an absence in any bleeding. Cycles can take up to six months to return to your normal.
Too much exercise and/or low body weight.
The optimum body fat percentage is 17-22%. A hormone called leptin is produced in fatty tissue. A reduction in this through excessive exercising and weight loss causes this and other hormones to drop.This contributes to irregular cycles.
In cave man times a starving Mrs Flintstone would not be able to sustain a pregnancy. The body would shut down and prevent pregnancies until it was convinced that both the body and environment were able to sustain life.
Too much stress.
Too much stress can cause a chemical response in the body.
The hypothalamus in the brain sends signals to the pituitary gland. This in turn signals the ovary and uterus to have a menstrual cycle. The hypothalamus is situated beside parts of the brain that have influence over emotions. Chemicals from these areas can stop both signals to and from the hypothalamus leading to irregular cycles. In cave man times this made sense. If there was too much stress either from the environment or emotionally it was not seen as a safe time for pregnancy. Cue snarling sabre tooth tiger
Polycystic Ovarian Syndrome
Polycystic Ovarian Syndrome is a common endocrine condition.It leads to the presence of small cysts growing on an ovary.
These cysts cause a hormonal imbalance. This can lead to a myriad of symptoms including irregular cycles, problems with ovulation and a delay in conception.
Undiagnosed thyroid conditions can affect fertility. Both hypo and hyperthyroidism can prevent ovulation.Hypothyroidism can lead to increased levels of a hormone called prolactin. When this is elevated ovulation may not occur.
Women moving towards menopause and a natural cessation of periods enter peri-menopause. This occurs about four years before the actual menopause and can affect the regularity of periods.
Some peri-menopausal women may not have periods for months or may experience spotting between periods. Some may notice heavier or lighter periods. All may be caused by fluctuations in hormone levels.
Please visit your GP initially if you have any cycle concerns.
One of the commonest causes of irregularity is Polycystic Ovarian Syndrome and is discussed in my next entry.