Do you really need to have a period every month?

It's estimated that women living today have 450 periods in a lifetime, which is about three times as many as our early ancestors [source: Kalb]. Today, women begin menstruating much earlier but have children much later. They also have fewer children and breastfeed for shorter periods of time, comparatively. Today's women also liv­e much longer. When you add up how much time our hunter-gatherer ancestors spent pregnant and breastfeeding, then they likely had only about 160 periods in a lifetime [source: Clark-Flory].

Historically speaking, then, the amount of menstruating that a woman does today seems a bit excessive. Is there any benefit to these increased troubles? It turns out there are a few cardiovascular benefits to those having menstrual cycles not regulated by the pill. Though menstruation is necessary to rid the body of the uterine lining that has built up in preparation for pregnancy, it also eliminates excess iron, which can be a risk factor for cardiovascular disease. Additionally, the menstrual cycle includes two weeks where women demonstrate significantly reduced blood pressure. As a result, women have fewer heart attacks and strokes while they're in their fertile years [source: Kelley]. An evolutionary biologist also posited that monthly menstruation flushes bacteria out of the reproductive system, serving as a form of protection for STDs and infertility [source: George].

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Some doctors, however, point out that by monthly menstruating, a woman's body is regularly enduring something that it was never meant to endure. This has health impacts both large and small. PMS and its attendant symptoms represent the smaller side of the spectrum, though to some women, calling such a condition "small" is a joke. A majority of women have experienced one or more premenstrual symptoms, which include headache, cramps, fatigue, mood swings, depression and insomnia. Studies indicate that these symptoms are often enough for women to miss class or work, or if they do show up, to exhibit decreased productivity. Women may also suffer from dysmenorrhea, which includes severe cramping, nausea and diarrhea [source: Henig]. Menstruating women are also at risk for anemia, endometriosis and ovarian cysts [source: George].

On the larger side of the scale is cancer. As far as cells go, ovulation and menstruation is a fairly violent process. During the menstrual cycle, hormones cause immature eggs, or follicles, to develop. At the point of ovulation, one follicle produces an egg, which scars the ovary. If the egg remains unfertilized, then the built-up uterine lining, or endometrium, is shed as a menstrual period, which in turn creates more scars. These scars cause cells to divide and regenerate, and if something goes wrong with that process, then you're looking at ovarian and endometrial cancer. When a woman is pregnant, thus giving those symptoms a rest, her risk for ovarian cancer at some point in her lifetime drops by 10 percent [source: Gladwell].

By preventing ­ovulation, then, oral contraceptives also lower the risk for ovarian and endometrial cancer. In a 2000 article in the New Yorker, writer Malcolm Gladwell posited that the pill's inventor, John Rock, might have had an easier time getting the Catholic Church to approve his invention had he marketed it as an anti-cancer pill rather than as a family planning tool. On the next page, we'll consider how oral contraceptives affect the menstrual cycle.

When the pill was being developed in the late 1950s, the inventors knew that they could control the length of a woman's menstrual cycle. A woman could have a period every 25 days, 45 days or even 90 days. A dosage of 21 active pills followed by seven placebo pills was chosen because it would mimic a woman's natural cycle. The inventors figured that maintaining a traditional 28-day cycle would help women adjust to the idea of taking birth control pills, and that monthly bleeding would also provide reassurance that the method hadn't failed. That was particularly important in a time when home pregnancy tests weren't the convenient option they are today. Inventor John Rock, a devout Catholic, also thought he could win approval for birth control from the Catholic Church by mimicking a woman's cycle as closely as possible.

­Rock's gamble failed, but over time, women did pick up on what Rock and his fellow inventors knew: that by skipping the week of placebo pills in their birth control pack, they could skip a period. Some women may have done this occasionally, in anticipation of a vacation or a hot date, while some women may have adopted the practice to avoid particularly painful menstrual periods.

It's worth pointing out that if a woman is on traditional birth control, she's not even having real periods per se. In a normal period, the uterine lining sheds because the egg remains unfertilized, while a woman only bleeds while on birth control because the lack of hormones causes the uterine lining to weaken. Bleeding while on birth control, as opposed to bleeding without birth control, doesn't serve any purpose for health.

If a woman doesn't need to bleed every 21 days, then making the jump to every 84 days, as regulated by Seasonale, isn't so weird, right? While many doctors and the FDA support extended-cycle menstruation, not everyone is convinced that menstrual suppression is a good idea. Dr. Susan Rako, who wrote a book on the risks of menstrual suppression, called it "the largest uncontrolled experiment in the history of medical science" [sources: Kelley, George, Fried].

Rako and other doctors opposed to menstrual suppression worry about a woman's hormonal levels. Oral contraceptives cause a drop in testosterone, which can affect libido, bone strength and heart health. And while less-frequent menstruation may prevent ovarian cancer, long-term use of estrogen has been linked with breast cancer [source: Fried].

There are no studies of long-term use of menstrual suppressing oral contraceptives, so there may indeed be hormonal surprises in the wings. Additionally, we don't know how fertility is affected after long-term menstrual suppression. Another unknown is how menstrual suppression affects adolescents, because most testing is performed on subjects older than 18. Any form of oral contraceptive can prove dangerous to a woman over 35 who smokes. The possible side effects and risks, including blood clots, are the same for these extended cycle birth control pills as other oral contraceptives, but so far one major drawback has been identified: breakthrough bleeding, or spotting, between periods. The amount of breakthrough bleeding led many women to withdraw from trials of extended cycle oral contraceptives [source: Kalb].

So while research has shown that about two-thirds of women would get rid of their period if they could do so safely, tampon makers may not need to cower in fear yet [source: Saul]. There are some women who will always want the monthly assurance that they're not pregnant. And, as we mentioned in the introduction, there are people who think that playing God with a woman's natural hormonal balance is tinkering with the very meaning of what it is to be a woman.

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