Family doctor

Important facts:

• Dysmenorrhoea is very common in young women.
• It is defined as a cramping pain in the lower abdomen occurring just before or during menstruation.
• Over 90% of cases can be classed as primary dysmenorrhoea. This means that there is no medical disease causing the pain and extensive diagnostic tests are not usually required.
• Treatment is effective in over 90% of cases and includes nonsteroidal anti-inflammatory medications (NSAIDS) and the oral contraceptive pill.
• Stopping smoking and leading a healthy lifestyle may also help diminish menstrual pain.

What are the causes?

Primary dysmenorrhoea:

This is by far the most common form. There is no underlying medical illness that causes primary dysmenorrhoea. The pain is caused by prostaglandins which are hormones that are normally produced by cells in the lining of the uterus (womb). When the period begins, these cells release prostaglandins as they are shed. Levels of prostaglandins are highest during the first two days of the period and this is when the symptoms are at their worst. Women with severe primary dysmenorrhoea produce more uterine prostaglandins.

Secondary dysmenorrhoea:

The pain of secondary dysmenorrhoea is due to a problem with the reproductive organs. These conditions are less common and will need more extensive medical testing to make a diagnosis. The conditions include:

• Endometriosis - This is the most common cause of secondary dysmenorrhoea. The inner lining of the uterus (endometrium) can sometimes develop on organs outside the uterus such as the ovaries, tubes and bowel. (See article on endometriosis)
• Pelvic inflammatory disease - This is an infection in the uterus or the fallopian tubes. (See article on this).
• Adenomyosis - In this condition the endometrium grows abnormally into the muscular wall of the uterus.
• Fibroids - These are benign (non cancerous) growths in the uterine wall.
• IUCD/IUD use - This is a form of contraception in which a small copper device is inserted into the womb to prevent pregnancy. As a result, periods can become more painful. Recently a new type of IUCD (Mirena) has been developed. It slowly releases a hormone into the womb which reduces the amount of bleeding and thus the severity of period pain. (see article on IUCD and Mirena).
• Cervical stenosis - The cervix (entrance to the uterus) can be abnormally narrow. Some people are born with this problem but it can also be a result of surgery to the cervix as well as other more rare causes.
• Cysts or tumors - On the ovaries, cervix, bowel, bladder or other pelvic organs.

What are the symptoms?

Typical symptoms include cramping, lower abdominal pain, and may also include backache, diarrhoea, nausea, vomiting, headache and lightheadedness.

The abdominal pain usually develops within hours of the onset of menstruation and peaks as the flow becomes heaviest during the first day or two.

Primary dysmenorrhoea usually presents during teenage years and often within 3 years of the first period. It is unusual for symptoms to start in the first 6 months after the first period, and if this is the case, it may alert your doctor to consider a problem with the shape of your uterus or cervix.

Dysmenorrhoea is sometimes confused with premenstrual syndrome (PMS). The two can be easily differentiated as PMS symptoms begin before the period (often up to a week or two) and resolve shortly after the period begins. There is usually abdominal bloating and discomfort with PMS (rather than the cramping pain of dysmenorrhoea), and PMS is often associated with breast tenderness, headache and irritability, or low mood.

Diagnosis:

Your doctor will make a diagnosis after listening to your description of the symptoms and sometimes by performing a physical examination. The examination should reveal no abnormalities in patients suffering with primary dysmenorrhoea. If you have typical symptoms of primary dysmenorrhoea as a teenager then you may not need an internal examination.

The possibility of secondary dysmenorrhoea may be raised if the following features are present:

• The period pain lasts longer than a day or two.
• You have previously had a sexually transmitted infection or have suffered with pelvic inflammatory disease.
• You have recently started a new sexual relationship and may be at risk of infection.
• Endometriosis may be considered if you have pain during sex, infertility problems or a family history of endometriosis.
• The physical examination reveals an abnormality such as an enlarged uterus or ovary.

If there is a suspicion of secondary dysmenorrhoea then further tests will need to be considered by your doctor. These will usually include a cervical smear test and swabs for infection. An ultrasound scan and a laparoscopy will need to be considered in some cases.

A laparoscopy is a brief surgical procedure performed under general anaesthetic by a gynaecologist. A small telescope is inserted into the abdomen just below the navel and this allows the pelvic organs to be viewed via a television screen.

The advantage of this procedure is that it allows accurate visualisation of the pelvic organs, and conditions like endometriosis can be accurately diagnosed.

What is the treatment?

NSAIDs (see article on NSAIDs)

Over 90% of patients suffering with primary dysmenorrhoea find effective relief with nonsteroidal anti-inflammatories (NSAIDs). These medications work by limiting the production and release of prostaglandins. There are many types of NSAIDs available but no single agent has been reliably shown to be more effective than the rest. There is a large individual variation in response to NSAIDs so it is wise to try a different type if there is a limited initial response.

It is important to take the treatment at the first sign of menstrual pain and to continue for as long as needed.

Oral Contraceptive (OC)

Some women may consider taking the OC to manage their period pain. When taken correctly this also provides the benefit of birth control but does not protect against sexually transmitted infections. The OC controls period pain by reducing the amount of blood loss. The hormones in the OC also stop ovulation (the monthly release of an egg). It may take up to three menstrual cycles (i.e. three months) before any benefit is perceived.

NSAIDs can be used in addition to the OC.

The injectable form of contraception known as Depo Provera is also effective in relieving period pain. (Please refer to the articles on oral contraceptives, NSAIDS, and Depo Provera).

If period pain is not relieved by the treatment outlined above then secondary dysmenorrhoea should be considered and the appropriate investigations performed.

Questions to consider:

1) What are the symptoms that will alert me to the possibility that there might be a medical problem causing period pain (secondary dysmenorrhoea)?

Answer: Painful periods that occur in the first six months following your first period, painful periods that occur later in life (i.e. older than 25 years), exposure to a sexually transmitted infection, period pain that lasts longer than a few days, pain during sex, and a family history of endometriosis.

2) When should I be referred to a gynaecologist?

Answer: If your doctor considers that secondary dysmenorrhoea may be the cause for your period pain then it would be usual for you to be referred to a gynaecologist.