What is menstruation?

The menstrual cycle occurs due to the rise and fall of hormones.  This results in the thickening of the endometrium (lining of the uterus) and the growth of an egg (which is required for pregnancy).  The egg is released from an ovary around the mid-cycle (day fourteen), the thickened lining of the uterus provides nutrients to an embryo after implantation.  If pregnancy does not occur, the lining is released in what is known as menstruation.

What is irregular menstruation?

Irregular menstruation, also known as menstrual disorders, is a common gynaecological issue that afflicts many women. A normal menstrual cycle lasts 28 – 35 days, and bleeding usually lasts between 3 – 7 days, but this varies between individuals.  Menstrual bleeding is considered irregular if it occurs more frequently than every 21 days or continue longer than 8 days.  Early, late or missed periods are also considered signs of an irregular cycle.


You may have irregular periods if:

  • Duration between each cycle starts to change (longer or shorter cycles)
  • More or less blood loss during a period than usual
  • Number of days that period last varies a lot
What causes irregular menstruation?

What causes irregular menstruation?

  • Emotional Stress
  • Eating Disorders such as anorexia or bulimia
  • Excessive weight loss or weight gain
  • Excessive exercising can often cause periods to be delayed or not come at all
  • Polycystic Ovarian Syndrome (PCOS)
  • Hormone Imbalances – Thyroid Disorders (Overactive – hyperthyroidism) or Underactive (hypothyroidism)
  • Pregnancy or breastfeeding
  • Age (when teens first start to have periods, their menstrual cycles may not always have the same schedule every month till several years later. In addition, missed periods, lighter or heavier periods are common as women near menopause)
  • A less common cause is severe scarring (adhesions) of the lining of the uterus


Maintaining a healthy lifestyle can help can help reduce the risk of some of the causes of irregular periods.  This includes exercising regularly to maintain a healthy weight, reduce stress and following a balance and healthy diet.

Menstruation Disorders

A regular menstrual cycle occurs every 21 – 35 days and bleeding may last from 2 – 7 days. At the start of your period, you may experience some cramping. Regularity of a period depends on age, body weight, stress or other underlying health conditions. Pre-menstrual syndrome (PMS) may include tiredness or bloatedness and are commonly experienced around a week before a period. Adolescents may also face abnormal menstruation, which are listed below.


Dysmenorrhoea (Painful Periods)

More commonly experienced in adolescents and young women, dysmenorrhoea refers to severe and frequent cramps experienced during menstruation. The release of a substance known as prostaglandin during menstruation causes the uterus muscles to contract as the lining is shed. Severe cramps can also be caused by conditions such as endometriosis, fibroids or cysts. Though the pain can be managed by painkillers, you may wish to consult an O&G specialist to find out the cause if it gets progressively worse.


Irregular Menses (Infrequent Menses / Overly Frequent Menses)

A common occurrence in adolescent girls, an irregular menstrual cycle is one that occurs less than 21 days (polymenorrhoea) or more than 35 days apart (oligomenorrhoea). Girls may not develop a regular cycle for several years after puberty and the menstrual cycle could either gradually regulate or stay irregular even in adulthood. Lifestyle changes including diet and adequate rest can help address the issue. However, if these self-care practices are not working well for you, request for further examination.


Menorrhagia (Excessive Bleeding)

Indications of menorrhagia include having to change a pad or tampon every 1 – 2 hours, having huge blood clots, having flooding episodes, having to use double pads to prevent overflow, or having heavy periods lasting for 8 – 10 days or more. Causes of menorrhagia include hormonal imbalances, which are common during the initial occurrences of menstruation. However, it could also be an indication of uterine fibroids, uterine polyps, endometriosis, or a bleeding disorder. Many women with menorrhagia suffer from anemia – tell-tale signs include the tiredness experienced by an individual or the pallor of their skin – due to excessive bleeding.


Amenorrhoea (Absence of Periods)

An adolescent may not experience any menstrual period by the age of 16 or may experience the absence of a period for 6 consecutive months without pregnancy. A delay in puberty, hormonal imbalances, or polycystic ovary syndrome (PCOS) could also result in amenorrhoea. The absence may also be caused by weight fluctuations, stress or excessive exercising.

When to talk to your doctor?

Irregular periods are common. But you might just want to check in with our gynaecologist and tell them you’re having irregular periods. We can do a quick safety check to make sure the cause for your irregular periods is nothing to be worried about.

If you find that irregular periods are taking over or making your day-to-day life difficult, then visit our specialist for a health check. Many find that their periods are more irregular during puberty or menopause. A missed period can also be an indication of pregnancy, so if you are unsure, consult our specialist.

If your periods suddenly change, you should also go see us. Maybe it’s because of stress, but better to rule out any other causes for sure.

Planning Ahead
You may wish to prepare a list of questions to ask before seeing us so that you will not miss out anything important. Ask for the appointment on a day when you know you will not be having your period. Be sure to bring a list of all medications and supplements that you are taking.
Can I walk in for an appointment or service?
We want to make sure we cater enough time for your visit with our doctor. As such, we strongly advise that you make a prior appointment with our staff. Our specialist will then meet you on the allocated time for a detailed discussion. Please call or email us for an appointment.
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Vaginal Bleeding during Non-Menstrual Period

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