Menstruation represents a part of woman's menstrual cycle which includes discharging of blood secretion and tissue debris from the uterus at about monthly intervals. It is common for women of child-bearing age to experience a variety of different symptoms before, during or after their menstruation.

Common complaints include pain in the back or the inner thighs, nausea, diarrhea, constipation, headaches, changes in sex drive, irritability and other mood changes. Conversely, women can sometimes experience positive sensations such as relief, euphoria, invigoration, creative energy, excitement, increased sex drive and more intense orgasms.

One of the frequent uncomfortable sensations that women experience during menstruation are uterine cramps. They can be divided into two distinct types – spasmodic and congestive cramps. Spasmodic cramping is caused by prostaglandins, chemicals that affect muscle tension. Congestive cramping causes the body to retain fluids and salt.

Premenstrual syndrome

Premenstrual syndrome (PMS) is a common term for a myriad of symptoms some women experience prior to each menstruation. Some of the more frequent physical signs of PMS include acne, lumpy or tender breasts, bloating, sleep problems, food craving and migraines. Psychological signs might encompass mood swings, fatigue, sadness, anger, anxiety (when estrogen predominates) or depression (when there is more progesterone).

The average duration of symptoms per month is six days, with peak severity two days before the first day of the menstrual flow. Possible etiologies of the condition are fluctuating hormone levels, increased sensitivity to normal levels of estrogen and progesterone, increased aldosterone and plasma renin activity, as well as neurotransmitter abnormalities (namely serotonin).

A more severe and disabling end of the spectrum of premenstrual syndrome is known as premenstrual dysphoric disorder (PMDD), which occurs in an estimated 2-9% of menstruating women. Although the symptoms of the condition can vary from woman to woman, they are relatively consistent from cycle to cycle, and tend to remit during pregnancy.

PMDD is characterized by mood symptoms that result in a significant disruption of a woman's baseline level of functioning across family, social, and occupational domains. The degree of disability and disruption of quality of life reported by women with PMDD is comparable to other depressive or anxiety disorders.

Dysmenorrhea

Dysmenorrhea is usually divided into two categories, based on its pathophysiology. Primary dysmenorrhea, defined as a painful menstruation in women with normal pelvic anatomy, usually starts during adolescence. It is defined as cramping pain in the lower abdomen that occurs just before or during menstrual bleeding, in the absence of other diseases.

Secondary dysmenorrhoea is menstrual pain associated with a specific disease such as endometriosis, myomas, endometrial polyps, pelvic inflammatory disease, and the use of an intrauterine contraceptive device. Pain from secondary dysmenorrhea usually occurs earlier in the menstrual cycle and its duration is longer when compared to common menstrual cramps.

The condition is caused by the release of prostaglandins and leukotriens in the menstrual fluid, resulting in increased uterine tone and stronger, more frequent uterine contractions. Elevated vasopressin levels have been reported in women with primary dysmenorrhea, and prostaglandins are also implicated in secondary dysmenorrhoea, albeit the accompanying pelvic disease has a dominant role in the pathophysiology of the condition.

The severity of dysmenorrhoea is highly associated with the duration of menstruation, younger average menarche, obesity, smoking and alcohol consumption. Anxiety, clinically manifest depression and disruption of social support networks have been associated with menstrual pain. Dysmenorrhoea, especially in its severe form, is associated with a significant restriction of activity and absenteeism from school or work.