A BRIEF HISTORY OF MENSTRUATION IN CULTURE AND MEDICINE

Menstruation has historically been cloaked by religious, social, and cultural myths and meaning. Menstrual blood and menstruating women have been surrounded by fear, taboo,* restrictions, and worship since ancient times. Cultural views on menstruation are diverse. The Beng people of the Ivory Coast believed that “Menstrual blood is special because it carries in it a living being. It works like a tree. Before bearing fruit a tree must first bear flowers. Menstrual blood is like the flower.”² In stark contrast it has been referred to as “the curse” by Judeo-Christians and is considered a sign of uncleanliness, or even evil, in some cultures.³ Menstrual blood was used as a panacea, a medicinal ingredient, an ingredient in casting spells, and even as a pesticide capable of making caterpillars drop from plants and insects die in the fields.⁴ Menstruating women were variably considered to be possessed by evil spirits or magic. 5 6 7

Medical attitudes regarding menstruation have fluctuated over the centuries, from menstruation and menstrual blood being perceived as a natural process—a woman’s “flowers,” as menstruation was described not only by the Beng but in the Treatise on the Diseases of Women, and Conditions of Women, part of the medieval compendium known as The Trotula, which remained the definitive text on women’s medicine for several centuries—to something capable of poisoning men and deforming children, as described by Pliny and others.^2,7 Hildegarde of Bingen, the famed German nun and healer (1098–1179) used the term flowers; however, she also attributes menstruation to “Eve’s sin in Paradise,” reflecting both positive and negative attitudes toward menstruation. Hippocratic and Galenic medicine viewed menstruation as the basis of women’s unique physiology. It was considered a necessary and healthy purgation upon which the health of the entire female body was dependent. Menstruation was seen as women’s inherent constitutional “coldness.” The inabilities to “cook” their nutrients thoroughly led to an accumulation of waste in the body that could only be gotten rid of through menstruation. Lack of menses (e.g., amenorrhea) was believed to lead to a pathologic systemic state. Normal menstruation, that is, the proper amount at the proper time, was considered to reflect a state of health.²

In contrast, however, around the first century bce, Pliny, a physician and prolific medical writer, wrote that menstrual blood could drive men and dogs mad, make vines wither, sour wine, and discolor mirrors, among other powers.^5,7,8 Pliny’s views, as well as others’ of his time, represented menstruation as poisonous or noxious, views that would contribute to misogynist medical views of women that have persisted.^1,2,4 Democritus wrote that “usually the growth of greenstuff is checked by contact with a woman; indeed, if she is also in the period of menstruation, she will kill the young produce merely by looking at it.”⁶

Negative attitudes about menstruation have not only influenced the practice of women’s medicine, but also the medical education of women. Western medicine historically viewed menstruation as a disease and an opportunity to treat women as fragile and weak.⁷ Well into the nineteenth century in the United States, the fact that women menstruated was considered proof of the inferiority of the female intellect. Menstruation was used as a justification for keeping women out of medical schools, based on the grounds that menstruating women needed increased rest—mentally and bodily.⁵

Women’s health reform and self-help movements throughout the twentieth century have played a major role in transforming and reshaping women’s, society’s, and medicine’s attitudes toward menstruation. It has become a more acceptable topic for conversation, evidenced in many ways, not in the least, by the mention of menstruation on television sitcoms, the openness of menstrual products advertisements on television and in print media, and articles in popular magazines. This is a positive trend allowing women to more openly seek information and medical care about menstruation and menstrual concerns. However, advertising also directly contributes to the perpetuation of cultural menstrual taboos—that menstruation is “dirty,” and suggestions that it should remain hidden. Educational films and advertisements from menstrual product manufacturers stress products’ abilities to keep safe the secret that the girl is menstruating and to help her feel fresh and clean, perpetuating the message that menstruation is shameful and dirty.⁹

Women’s own personal and cultural views on menstruation also vary substantially. Menstruation may be considered a happy event, or a sign of uncleanliness—both attitudes persisting even in a single culture.¹⁰ A correlation has been asserted in feminist literature that a woman’s attitudes toward menstruation and can influence her physical experience of menstrual symptoms.⁷ In one study analyzing menstrual attitudes, women were asked to describe their menstrual periods. Terms were rated as positive (such as “red friend,” “my buddy”), negative (such as “the curse,” “pain in the ass”), or neutral (such as “period,” “surfin’ the crimson wave”). In the groups combined, most terms were either neutral (46%) or negative (37%). There was a tendency for women in the negative group to employ negative terms (52% of negative group women used solely negative terms versus 18% in the positive group), whereas 55% of women in the positive group employed neutral, not negative terms.⁹ Women in the negative group used negative terms significantly more than did women in the positive group. Many women consider menstruation somewhat of an inconvenience, but nonetheless, a natural event. Increasingly, American women are reframing menstruation as a celebration of women’s femininity and women’s connection to the rhythms of the earth and the moon.

WHAT IS NORMAL MENSTRUATION?

Menstruation is a cyclic process occurring in most women between 12 and 50 years of age. It generally occurs without difficulty, although there may be some normal sense of inconvenience accompanying the period. The variation in the interval between menstrual periods, the duration of each menstrual period, the amount of blood loss, the associated discomforts or lack thereof, and the subjective psychoemotional experience of menstruation among women is so great as to make it difficult to define “normal menstruation.” There is a wide range of normal variation.

It is necessary to determine whether a pattern, symptom, or concern is normal for the individual woman in the context of her own gynecologic and menstrual history, as well as against objective measures. Certain characteristics of menstruation can be a reflection of an underlying pathologic process or may predispose a woman to the development of chronic disease.¹¹ For example, metrorrhagia predisposes to anemia, and the irregular menstrual cycles associated with PCOS (see PCOS) can predispose a woman to diabetes and consequently, heart disease. Women with long or highly irregular menstrual cycles have a significantly increased risk for developing type 2 DM that is not completely explained by obesity.¹² Persistent deviations from the woman’s own norms, as well as major deviations from accepted standards, require further evaluation.

ONSET, FREQUENCY, AND DURATION OF MENSTRUATION

The onset of the first menses (menarche) typically occurs between the ages of 10 and 16 years old (see Puberty, Menarche, and Adolescence). The menstrual cycle is generally irregular and anovulatory for the first several years after menarche, reaching a regular length and duration by 5 to 7 years after menarche. Variations outside of this range are generally normal, but could be signs of precocious puberty or amenorrhea; sometimes symptoms of underlying medical disorders (see Puberty, Menarche, and Adolescence, as well as Amenorrhea).

A woman will experience from 300 to 400 menstrual cycles in her lifetime. Cycle length is controlled by the rate and quality of follicular growth and development, which varies in individual women.¹ Based on several observational longitudinal studies of thousands of women around the world, it was determined that at age 25, 40% of women had 25- and 28-day cycles, and from ages 25 to 35 60% had 25- to 28-day cycles. The average cycle length is 26 to 34 days.¹³ Only 0.5% of women experience cycles shorter than 21 days and 0.9% cycles longer than 35 days. At least 20% of women experience irregular cycles.¹ The length of the follicular phase is the primary determining factor in cycle length.

Menstrual bleeding lasts 3 to 6 days in most women, although there is variation in cycle length from 2 to 12 days after the start of ovulatory cycles. Longer periods (>8 days) are associated with anoluvation.¹³ The heaviest flow is consistently on day 2 of the cycle. Normal blood loss is considered 30 to 80 mL. Small clots are considered normal; large clots may suggest the need for further evaluation.⁷

The duration and amount of bleeding declines slightly (by about a half a day per cycle) in women over age 35. However, women approaching menopause often experience significantly heavier bleeding than younger women.¹³

Although some women describe their periods coming “like clockwork,” most describe some amount of irregularity over the course of menstrual life cycle, even if it is only occasional. The endocrine system is easily affected by numerous factors: stress, changes in amount of daily and nightly light exposure, sleep patterns, diet, travel, amount of exercise, illness, and so forth. It is normal for women to occasionally experience an irregular period, a lighter or heavier period, a “crampy” period, or even to miss a period in the absence of pregnancy or lactation. It is when irregularity recurs repeatedly, presents with an acute problem (e.g., sudden, heavy, or unremitting vaginal bleeding), or occurs in the absence of other explainable factors that one might suspect a disorder.

Women in their late thirties and forties often begin to experience some degree of irregularity of menstrual frequency, duration, and amount of blood loss because of a decline in ovarian function as they approach menopause. In their late thirties, women experience a shortening of their cycle because of increased production of FSH, a result of follicle numbers beginning to decline. However, between 2 and 8 years prior to menopause, the cycles again lengthen.¹ Approximately 50% of women experience a cycle of 120 days or longer in the year prior to menopause, and 20% experience a cycle of this length or longer within 2 to 4 years of their final period.¹³ The average age of menopause in the United States is 51 years old.¹⁴

FREQUENCY AND TYPES OF MENSTRUAL DISORDERS

Menstrual dysfunction is defined in terms of bleeding patterns, for example, amenorrhea (lack of menstruations), menorrhagia (excessive bleeding during menstruation), or polymenorrhea (frequent menstruation); ovarian dysfunction for example, anovulation and luteal deficiency; pain (dysmenorrhea); and premenstrual syndrome. Irregular menstruation is estimated to range from 2% to 5% of the general population, and up to 66% among athletes.¹⁵ In the United States, approximately 2.9 million office visits are made annually by women age 18 to 54 for menstrual problems.^7,16 Two-thirds of these women contact a doctor regarding menstrual problems each year, and 31% report spending a mean of 9.6 days in bed annually. Among young women, dysmenorrhea is the most common cause of time lost from work or school. The costs of menstrual disorders to US industry have been estimated to be 8% of the total wage bill, and the impact is particularly acute in industries that employ women predominantly.¹⁶ Interestingly, it is estimated that primitive, hunter gatherer women, over the course of an average lifetime, experienced only one-third as many menstrual periods as do modern women because of later age at menarche, earlier and more frequent pregnancies, and breastfeeding, suggesting that modern women experience a significantly greater lifetime exposure to estrogen, which may be partially responsible for increased health risks. Traditionally, factors such as later menarche, earlier first pregnancy, breastfeeding, and earlier menopause may have played a protective effect against, for example, breast and gynecologic cancers.¹⁶ Menstrual disorders also predispose women to other risks, for example, anemia, osteoporosis, cancer risks, diabetes, and cardiovascular disease.

In spite of the significance of menstruation in women’s lives and the high incidence of menstrually related health problems in society, there is surprisingly little epidemiologic evidence on menstrual disorders and associated risk factors, and no prioritization of research in this area.^11,16

Subsequent sections of this chapter address these dysfunctions either individually or as part of a larger syndrome in which they occur.

FACTORS AFFECTING THE MENSTRUAL CYCLE

Numerous factors influence the menstrual cycle, including a woman’s nutritional status, stress levels, body weight, exercise patterns, attitudes and beliefs about menstruation, and environmental and workplace exposures. Investigation into these can sometimes explain dysfunction; corrections can often restore physiologic and emotional balance. A holistic approach to preventing and treating menstrual dysfunction should always include consideration of possible social and lifestyle issues.

PROMOTING HEALTHY MENSTRUATION

The health care profession has an obligation to promote menstrual education. We must have an understanding of reproductive physiology in order to impart it to our patients, and we must be sensitive to the need to present a positive attitude regarding sexual and reproductive functions.