Do we need to menstruate?

It has been thought by generations of mothers and daughters that regular menstrual cycles are a sign of good health. A regular menstrual period is usually a sign of prior ovulation and thus fertility. Certainly the absence of menstrual cycles in any woman for more than three months deserves evaluation for several reasons. The obvious, is she pregnant, and the not so obvious hormonal or physical problems that can contribute to the absence of menstrual periods. However, disorders of menstruation (such as heavy bleeding or severe cramping) affect up to 2.5 million American women. With the availability of safe and effective methods to eliminate monthly bleeding is it necessary to have a monthly period?

A woman will experience approximately 450 menstrual periods during her lifetime. Contrast this to our ancestors, who had later onset of puberty (and thus menses), more pregnancies, longer periods of breastfeeding (which suppresses menstrual periods) and an earlier menopause, who had only 160 menstrual periods during her lifetime. Although many women have no problems with their periods most of us have had a period at an inconvenient time and wondered "why do I have to deal with this every month?"

Oral contraceptives are effective in alleviating menstrual disorders along with providing contraception. Oral contraceptives have been designed to mimic a woman’s menstrual cycle, with three weeks of active pills then 7 days of sugar pills when a withdrawal bleed will occur. Note that I didn’t call this a menstrual period. The bleeding that occurs during the sugar pill week is a response to the withdrawal of the hormones that affect the uterine lining. It is not a sign that ovulation has occurred. The pills were originally made this way because it was thought women would "want" a menstrual period as a sign they were normal! However many women continue to experience menstrual symptoms (e.g. headaches, cramping, bloating or breast tenderness) during the week of sugar pills.

For years gynecologists have known that having women skip the placebo pills and start on a new packet of oral contraceptives is an easy way to take care of bothersome or inconvenient menstrual bleeding. For women who suffer from menstrual disorders this may significantly improve their quality of life. As long as the lining of the uterus is suppressed with hormones (estrogen plus a progestin or progestins alone) there is no need to have a menstrual period. Currently a new formulation of oral contraceptives called Seasonale is in clinical trials; if approved by the Food and Drug Administration this will be packaged such that only four menstrual periods will occur each year.

Other medications in addition to oral contraceptives are available that can safely suppress menstrual periods. Depo-Provera is an injectable contraceptive (consisting of the hormone medroxyprogesterone acetate) given every 3 months. About 50% of women who continue with the method will have no menstrual bleeding after one year. Some women do not tolerate side effects of the medication (such as irregular spotting and weight gain). Another option is the Mirena intrauterine device that is inserted into the uterus and releases a low dose of the hormone levonorgesterol. Along with providing reversible and long acting contraception it also reduces menstrual bleeding by 94%. Although only recently available for use in the USA it has been used in Europe for at least 10 years for both contraception and control of excessive bleeding.

Critics of suppressing menstruation with contraceptives state that it is not "natural" and we have no long-term data as to its safety. I would leave the decision as to whether this is natural or not to each individual woman. We have no reason to think that continuous use of oral contraceptives is harmful. For women who are miserable during their menstrual periods eliminating or reducing the number of bleeding episodes per year can significantly improve their quality of life.