Irregular Periods

Irregular Periods

Irregular periods are often one of the first signs that a woman is approaching menopause. Though the exact symptoms of irregular periods vary depending on a woman’s unique cycle, most women will experience irregular periods for three to ten years before periods stop completely. In fact, only 10% of women reach menopause without any irregular periods.

As menopause approaches, women’s hormones become imbalanced and, because the menstrual cycle is entirely dependent upon hormones, irregular periods often occur. Keep reading to learn more about irregular periods and their symptoms, common causes, and treatment options.

What are irregular periods?

In order to discuss irregular periods, it is helpful to first understand what a “normal” period is. While every woman is different, normal periods are typically described as having an interval of 25 to 31 days from period start to period start, with bleeding lasting approximately five days. The average amount of blood loss during a normal period is two to eight tablespoons.

While this is a “textbook” definition of normal periods, some women may experience menstruation differently. Thus, irregular periods might be characterized by symptoms that are unusual for them.
Irregular periods, then, are alterations in a woman’s typical menstrual cycle that persist for several months. Irregular periods are those characterized by abnormal bleeding and/or unusual cycle lengths.

As discussed, irregular periods are essentially characterized by what is irregular for each individual woman. However, there are specific symptoms that can help to determine if irregular periods are occurring.

Fertility and irregular periods

Many women wonder about their fertility when they begin to experience irregular periods. It is important to remember that pregnancy can occur anytime before menopause, even if a woman’s periods are irregular. It is not uncommon during perimenopause to go months without a period, only to have it return. During this time, it is still possible to become pregnant.

What causes irregular periods during menopause?

Several factors can cause irregular periods, but for women approaching menopause, the most likely cause is fluctuating hormonal levels experienced typically between the ages of 45 and 55. A woman’s menstrual cycle cannot be separated from her hormones, because her hormones, particularly oestrogen and progesterone, drive the process. When hormone production begins to taper off, periods often become irregular.

To better understand the hormonal cause of irregular periods, it’s helpful to learn what functions the hormones play during menstruation.

Role of hormones during the menstrual cycle

While menstruation is orchestrated by many hormones, progesterone and oestrogen are the primary hormones responsible for irregular periods.


Oestrogen is responsible for thickening the uterine lining before ovulation. As levels of oestrogen become erratic in menopause, this lining is often shed irregularly and can lead to heavy bleeding.


Progesterone is responsible for triggering the shed of the uterine contents after ovulation when fertilization hasn’t occurred. It is also responsible for controlling the intensity and duration of menstrual bleeding. When it declines in menopause, it can lead to irregular periods. During anovulation, which is common with irregular periods in menopause, progesterone is not produced. This can lead to oestrogen build-up.

As production of these two hormones so integral to the menstrual cycle begins to decrease prior to menopause, periods are usually affected. Before decreasing to a constant low level, oestrogen and progesterone levels will often fluctuate wildly and cause irregular periods.

Other causes of irregular periods

Although hormonal imbalance is the primary causes of irregular periods during menopause, there are some health conditions and lifestyle triggers that can causes irregular periods.

If you would like to know more about how Irregular Periods in Menopause can be resolved, please fill in our enquiry form.

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