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Periods (also known as menstruation)

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Periods (also known as menstruation)


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Periods, menstruation

Women's health

A period, also called menstruation or menses, is bleeding from the vagina that occurs in adolescent girls and women. It normally happens once a month, every 28 days, although in some it can occur anytime between every 24 days and every 35 days.

Periods are a normal part of the menstrual cycle which helps the body prepare for the possibility of becoming pregnant. Periods will usually start in girls between the ages of 12-13 years, but can occur anytime between the ages of 9-16 years, and will continue unless pregnant until the menopause. The first menstrual period is known as the menarche and is one of the later stages of puberty.

Each menstrual cycle begins on the first day of bleeding and continues until the first day of the next period. Bleeding usually lasts for 4-5 days, being heaviest during the first two days, but it can last up to 10 days. The amount of blood loss can vary from period to period and woman to woman, but normally amounts to about 50ml.

When a girl reaches puberty her body begins to produce hormones that control the menstrual cycle and which bring about changes that are necessary for reproduction.

The menstrual cycle can be divided into a series of stages:

Under the influence of a variety of hormones, immature cells called follicles begin to grow and develop in the ovaries. At the same time, under the influence of the hormone oestrogen, the lining of the uterus (the endometrium) thickens. This stage is known as the follicular stage and normally occurs between day 5 and day 13 of the cycle.

Around day 14 of an average length cycle, the fully developed follicle bursts to release an egg or ovum. This process is known as ovulation. The released egg enters the fallopian tube and starts to travel towards the uterus.

The part of the follicle that remains after ovulation stays in the ovary and changes into a structure called the corpus luteum which secretes large amounts of the hormone progesterone. Under the influence of this hormone, the lining of the uterus continues to thicken and develop in preparation to accept the egg if it is fertilised. This stage is called the luteal stage and normally occurs between day 15 and day 28 of the cycle.

If the egg is fertilised it will fasten to or become implanted in the endometrium and the corpus luteum will continue to produce progesterone. Continued secretion of the hormone maintains the lining of the uterus and allows the fertilised egg, or embryo as it is now called, to develop into a baby.

If the egg is not fertilised and implantation does not occur within about 2 weeks, the corpus luteum will die. Levels of progesterone drop, the endometrium is no longer maintained and so it starts to break away from the rest of the uterus and menstruation begins.

Although, menstruation occurs at the end of these stages, menstrual cycles are counted from the first day of bleeding because this is the most recognisable time of the menstrual cycle and therefore the easiest point from which all other stages can be measured. For this reason, the menstrual stage is counted as day 1 to day 4 of the cycle.

Bleeding from the vagina is the most obvious and normal part of menstruation and many women regard their periods as a sign that their body is working normally.

Other changes that may occur around the time of a period include:

  • Breast tenderness
  • Headache
  • Backache
  • Feeling sick
  • Feeling bloated

These changes or feelings usually stop or ease a day or two after the period begins.

As the levels and type of hormone change during the menstrual cycle, feelings and emotions may also change.

Although menstruation is perfectly natural, there are a number of conditions associated with the menstrual cycle or which can affect menstruation which can be mentioned here:

Amenorrhoea - a prolonged absence of menstruation. The most likely time that amenorrhoea occurs is during pregnancy, but it can occur in women who are underweight due to excess dieting or anorexia, and in ballet dancers and athletes who over-train.

Irregular periods - the term used to describe when the length of the menstrual cycle varies by more than 8 days.

Heavy periods - also known as menorrhagia. Describes heavy blood loss in excess of 80ml.

Painful periods - also known as dysmenorrhoea. Pain in the abdomen and possibly extending to back and thighs experienced during the period.

Premenstrual syndrome - also known as PMS or premenstrual tension (PMT). Headache, bloating, irritability and tearfulness experienced a few days before the start of menstruation.

Menopause - the end of menstrual cycles and the end of the woman's reproductive life.

Medical treatment is not normally necessary as menstruation is a normal, healthy process, but treatments may be used if menstruation is causing problems.

For example, if dysmenorrhoea or period pain is causing a lot of discomfort, simple painkillers such as paracetamol or ibuprofen will help. (see separate article on period pain)

If premenstrual syndrome is interfering with the woman's life, there are a number of treatments that can help improve the symptoms, such as water tablets (diuretics) to relieve bloating, painkillers, antidepressants and hormonal drugs. (see separate article on premenstrual syndrome)

With heavy periods, drugs may be used to reduce blood loss. (see separate article on menorrhagia)

When to see your doctor
You should see your doctor if:
  • Menstruation has not started by the age of 16
  • Your period suddenly stops
  • A menstrual period lasts for more than seven days
  • You experience excessive bleeding
  • You experience excessive pain during your period
  • You suddenly feel ill while using tampons
  • You bleed more than a few drops between periods

Coping with periods
Although menstruation is a natural process, the experience can be alarming for a young girl who starts her periods well before her teens. If you are a parent or guardian of a young girl, it is important that you are aware of her development and explain to her that the changes happening in her body are normal and just part of ‘growing up’. Talk to her, tell her what to expect and share any feelings and worries that she may have.

Once periods begin you will need to help her choose a feminine product from the various ones available from pharmacies or supermarkets. Comfort and absorbency are the main features that need to be considered. As the amount of blood may vary, different types of products may want to be used at different times during the period.

Feminine products can be divided into two basic categories: sanitary pads and tampons.

Sanitary pads are worn inside underwear where they collect the menstrual flow. They come in different sizes, thicknesses, and styles.

Tampons are inserted into the vagina and also come in various sizes and absorbency categories and can be chosen according to the amount of menstrual flow.

The absorbency of a tampon can be determined by how often it needs to be changed. On average, tampons should be changed every four to six hours. The tampon with the least absorbency necessary should be used. Tampons can be comfortable to wear and may be a good choice for active girls.

Advise her to avoid using tampons overnight, always to check that the last tampon has been removed before inserting another one, and to remember to remove the tampon when the period has stopped. There is a rare condition known as toxic shock syndrome (TSS) connected to using tampons. The higher the absorbency of tampons used, the higher the risk for TSS so it is best to choose one with the lowest absorbency necessary.
Healthy Tips
  • Try to avoid drinks containing caffeine, such as coffee, tea or cola.
  • Exercise and staying fit can often help to ease pain. Walking, swimming or cycling can be very effective.
  • It is important to try and relax and avoid stress. Yoga, massage and generally avoiding stressful situations appear to help relieve period pain.
  • Some women find that heat can ease the discomfort. Try holding a hot water bottle or heat pack (warmed in the microwave) on to your stomach or back.
Reviewed on 20 April 2011