Dysmenorrhoea means painful periods. It is the most common symptom of endometriosis. In a recent survey of women with endometriosis by the Endometriosis Association, 81% of the women had experienced dysmenorrhoea.
According to medical textbooks there are two types of dysmenorrhoea: primary and secondary.
Primary dysmenorrhoea is said to be the ‘cramping’ type of dysmenorrhoea that typically affects teenagers. It usually begins a year or two after the onset of menstruation and tends to lessen by the age of 2 5, or after childbirth. The pain usually begins with the menstrual flow and lasts for only one or two days. It is often accompanied by nausea, vomiting, diarrhoea, dizziness and fainting. This type of dysmenorrhoea is generally believed by the medical profession to have no relationship to endometriosis.
Secondary dysmenorrhoea is the ‘grinding’ or ‘boring’ type of menstrual pain which is usually due to an underlying condition of the reproductive organs. According to the medical profession it typically appears in women who are in their 20s and 30s. This is the type of dysmenorrhoea that is generally believed to be associated with conditions such as pelvic inflammatory disease (PID), fibroids and endometriosis.
The pain of dysmenorrhoea due to endometriosis may be mild, moderate or severe and may be described as constant, deep inside, sharp, stabbing, knife-like, nagging, aching, burning, throbbing, dull, boring or cramping. It may be located in the centre or on one or both sides of the abdomen. The pain may radiate into the vulva, pubic bone, lower back, rectum, buttocks, groin or thighs. It may be more severe when using the bowels or passing urine, and may be accompanied by nausea, vomiting, and diarrhoea and/or constipation.
The pain may begin one to several days before the start of the period, gradually becoming more severe, particularly once the menstrual flow begins. The pain may last for the first one to two days or continue throughout the entire period. Usually the pain is most severe on the first or second day. It has been reported that the pain worsens and peaks at the end of the period although this pattern is not common.
It is not known precisely what causes the dysmenorrhoea associated with endometriosis but it is probably due to several reasons. One is that the bleeding from the endometrial implants causes irritation to the surrounding tissues. Another possibility is that the pressure resulting from the swelling of the implants and cysts causes pain in the immediate area in much the same way that a boil causes pain. It is also possible that the release by the endometrial implants of chemicals known as prostaglandins causes pain. Irritation to neighbouring organs, such as the bowel or bladder, by the implants of endometriosis can also lead to pain in those organs.