By Rachel Edlin, MD
Faculty peer reviewed
A 29-year-old female patient with a history of iron deficiency anemia and heavy menstrual periods comes into the clinic for a regular visit. She is tired of iron supplementation and its associated constipation. As she is currently on oral contraceptive pills, you recommend using these to reduce her menstrual period to four times a year. She asks, “Is that really safe?”
Is menstruation necessary?
Monthly menstruation is not the historical norm. Compared with modern women, women in prehistoric times experienced later menarche, earlier first birth, longer duration of breastfeeding, higher parity, and earlier menopause.1, 2 As a result, these women probably had far fewer periods, about 160 ovulations over their lifetime, versus modern women who experience an estimated 450 lifetime episodes of menses.3 There is evidence to suggest that this pattern of frequent, repetitive menstrual cycles may actually increase health risks.
Fewer ovulatory cycles have been found to be protective against breast and gynecologic cancers.2 Moreover, by not menstruating, a woman is avoiding the sharp changes in hormone levels that regulate this bleeding. Eliminating these fluctuations may help some women avoid the mood and personality changes of premenstrual syndrome. In addition, diseases directly caused by menstruation such as endometriosis would improve. Endometriosis causes great discomfort, contributing to painful intercourse and infertility. And, catamenial conditions, such as epilepsy and arthritis, would not worsen cyclically. Finally, frequent ovulation and menses also contribute to anemia and heart disease. Anemia, in turn, has been shown to cause a host of symptoms including fatigue and shortness of breath as well as hindering learning.4
Is monthly menstruation natural?
The first oral contraception, studied in the 1950’s, consisted of 21 days of active drug followed by 7 drug-free days. It is critical to understand that the bleeding following the 21 days of active oral contraceptive pills bears little biological resemblance to a menstrual period. Oral contraceptives act by inhibiting the release of follicle-stimulating hormone and luteinizing hormone, thereby preventing growth of the endometrial lining and ovulation. Instead, the oral contraceptive provides hormones that maintain a thin endometrium. During the interval after the 21st day, when a woman stops taking active tablets and switches to placebo, those hormone levels drop and bleeding results. This bleeding is not related to endometrial build-up.5
There is no evidence of any health benefit from taking the placebo tablets for 1 week each cycle.4 Instead, the 21/7 pattern was generated to make the idea of an oral contraceptive more acceptable to women, clinicians, and the church.3 So, the monthly bleeding that oral contraceptive users experience is not biological. Moreover, a recent study showed that nearly all hormonal symptoms (pelvic pain, headaches, bloating, and breast tenderness) were reported more frequently during the 7-day hormone-free interval than during the 21 days of active hormones.6 Thus, this monthly menstruation is neither “necessary” nor “natural”; instead, it is the source of hormonal symptoms.
Experience with reducing menstrual frequency3
Reducing menstrual frequency by utilizing continuous administration of an oral contraceptive regimen was first studied in 1977 by Loudon et al.7 In this study, 196 women took a combination oral contraceptive (50 μg ethinyl estradiol and 2.5 mg lynestrenol) for 84 days followed by 6 pill-free days. Women reported breakthrough bleeding, particularly in the first three months, as well as side effects similar to those in women on a conventional oral contraceptive regimen. Interestingly, 91% of the study participants who completed the trial refused to revert to a monthly oral contraceptive regimen when given the option, preferring to continue a trimonthly regimen.
With modern oral contraceptive regimens, side effects have been further reduced. As hormone-related symptoms in oral contraceptive users were found to be focused during the 7-day hormone-free interval, Sulak et al studied whether these symptoms would be further reduced by extending the active pill duration to three months.8 In fact, all women who extended the use of active oral contraceptives noted both a delay in onset and a decrease in severity of menstrual-related complaints.
Medical therapy does not irreversibly impair fertility. Options for hormonal contraceptives that reduce or eliminate monthly uterine bleeding include oral estrogen-progestin contraceptive pills, intrauterine contraception, depot medroxyprogesterone acetate injections (eg, Depo-Provera), transdermal contraceptive patch (eg, Ortho Evra), and contraceptive vaginal ring (eg, NuvaRing). Of these options, oral contraceptive pills have now been specifically designed, marketed, and approved to decrease menstrual bleeding.
Seasonale was designed to decrease menstrual bleeding to four times per year. Each pack contains 84 active tablets (ethinyl estradiol 30 mg and levonorgestrel 150 mg) followed by 7 placebo pills. This formulation (now available as a generic) provides both high contraceptive efficacy and is also safe and well tolerated.9 More recently, Seasonique was approved. This formulation has seven days of 10 mg ethinyl estradiol instead of placebo pills and may decrease breakthrough bleeding compared to Seasonale.10
Finally, Lybrel (ethinyl estradiol 20 mg and levonorgestrel 90 mg) is the first low-dose combination oral contraception designed to be taken 365 days a year, without a placebo phase or pill-free interval. In clinical trials, after one year of use, 59% of women achieved amenorrhea, 20% experienced spotting that did not require any sanitary protection, and 21% percent required sanitary protection due to breakthrough bleeding. Contraceptive efficacy and safety is similar to that of other oral contraceptives, except for higher rates of breakthrough bleeding.11
As the above formulations are not yet available as generic medications, it is important to note that another common practice for those interested in menstrual suppression is to take any monophasic oral contraceptive pill (such as Loestrin or Ortho-Cyclen) and simply start a new pack instead of taking the 7 days of placebo pills. By further manipulating the ratio of active to placebo days, it may also be possible to decrease breakthrough bleeding. For example, a 24/4 regimen rather than the traditional 21/7 regimen may be a favorable balance between suppressing menstruation and limiting breakthrough bleeding.
Interestingly, there are several non-pill options for menstrual suppression.12 The contraceptive vaginal ring (NuvaRing) can be inserted continuously rather than including a ring-free week. Alternately, a subcutaneous injection (Depo-Provera) can eventually lead to menstrual suppression. Lastly, intrauterine contraceptive devices such as Mirena (levonorgestrel) lead to a lighter menses in all patients, with many becoming amenorrheic. These devices have additional benefits including not requiring a daily pill or injections, reversibility, and reduced side effects due to a very low level of systemic hormones.
Women and health professionals are conditioned to think of monthly menstruation as “natural.” In fact, this frequent cycling may be detrimental to women’s health. While birth control pills have been accepted for many years, their design to mimic the monthly bleed has perpetuated the myth of a required monthly menstrual bleed. Since the 1970’s, women have been safely extending their oral contraception to exclude hormone withdrawal and its resultant bleed. As women become more knowledgeable about the safety, efficacy, and potential desirability of menstrual suppression, more patients will be able to tailor oral contraceptive choices to their own needs.
Commentary by Dr. Veronica Lerner
The many medical benefits of menstrual suppression include prevention of endometriosis, pre-menstrual syndrome, menorrhagia, chronic pelvic pain, hirsutism, polycystic ovarian syndrome, and migraine from estrogen withdrawal. There are social benefits as well: convenience (beach vacation), less money spent on hygiene products (yes, tampons are expensive), fewer missed school or work days (I’ve written plenty of “excuse” letters for work on this matter), and improved quality of life. That being said, some women want to get a period every month to assure themselves that they are
“healthy” and not pregnant. But surveys indicate that 2/3 of women would prefer to menstruate less frequently than once a month even if that involved hormonal manipulation.
Dr. Edlin, is a recent graduate of the Class of 2010, NYU School of Medicine
Peer reviewed by Veronica Lerner, MD Assistant Professor, Department of Obstetrics and Gynecology
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