Do Women Need to Have Periods?

This is actually not a silly question. Birth control pills on the market such as Seasonale allow women to postpone having their period for three months and to only have four periods total per year. The way these oral contraceptives (OCs) work is relatively simple. Monthly birth control includes a withdrawl phase where the progesterone is removed. Without the hormonal support the endometrium dies, and the woman menstruates. OCs that extend the cycle to 3 months simply exclude the withdrawl phase for two of those months.

However, this begs the question as to whether the withdrawl phase is necessary at all. Do women even need to have their period?

Good evolutionary arguments could be made that women in more primitive societies had far fewer total periods in their lifetime than women do today. Partly this was do to the fact that they were pregnant a lot of the time or were prevented from ovulating by lactational amenorrhea. Partly this is due to the fact that they often died in childbirth. Thomas and Ellertson, writing in the Lancet, have argued that the monthly periods women have in modern societies are not the norm:

Monthly menstruation for decades on end is not the historical norm. Women in prehistoric times, as estimated by research among contemporary hunter-gathered populations, probably had far fewer periods (about 160 ovulations over their lifetime) than modern women. Our foremothers most likely experienced later menarche (around 16 years of age), earlier first births (19.5 years), frequent pregnancies (on average six livebirths), and long periods of breastfeeding between pregnancies, with births at intervals of 3 years. By contrast, the modern woman living in an industrialised country begins menstruating earlier (on average 12.5 years of age for American girls), first gives birth later (24 years), has fewer pregnancies (two or three), scarcely breastfeeds (3 months per birth, with half of American infants never breastfed at all), and undergoes menopause later. She can expect about 450 periods in her life. Current menstrual patterns are in this sense new and unproven as to their health effects.

Furthermore, there is plenty of modern evidence that amenorrhoea is often healthier than the alternative. If a woman is not menstruating, she is probably also avoiding the sharp changes in hormone levels that regulate this bleeding. Measures to eliminate these fluctuations may help some women to avoid those mood and personality changes of premenstrual syndrome (PMS) that do not stem from problems with the receptors for these hormones. In addition, diseases directly caused by menstruation such as endometriosis would improve; and catamenial conditions (such as epilepsy and arthritis) would not worsen cyclically. Frequent ovulation and menses also contribute to anaemia, some reproductive cancers and heart disease, as well as other health threats. Anaemia in turn has been shown to hinder learning; similarly endometriosis causes great discomfort, contributing to painful intercourse and infertility among other conditions.

As they state, continuous menstruation can have health consequences that range from unpleasant to life-threatening. Aside from relatively common cycle-related complaints such as bloating, cramping, swelling, back pain, and headaches, there is anemia, uterine fibroids, endometriosis and ovarian cancer.

We have the technology (think the 6 Million Dollar Woman) to completely prevent ovulation and the menstrual cycle -- by using oral contraceptives continuously. However, up until recently it remained a question whether it was safe and effective to do so.

Writing in the journal Contraception, Archer et al. evaluated the health consequences of continuous use of oral contraception for one year without a withdrawl phase and compared it to the use of monthly contraceptives with the withdrawl phase included. The continuous regimen was 90 ug levonorgestrel/20 ug ethinyl estradiol (continuous LNG/EE) taken once per day -- which is relatively comparable to standard monthly birth control.

Their results are promising with some caveats.

  • First, they found that for the majority of women this regimen is effective at preventing bleeding and spotting when used over the year. At the beginning of the year, the percentage of women who actually have their menses prevented is less, but it does steadily increase. This result is summarized in the chart. (Incidentally a Pill Pack corresponds to one month supply of the contraceptive.)


  • Second, the safety profile for this regimen was comparable to monthly OCs:

    The safety profile of continuous LNG/EE was comparable to that of a 21-day cyclic regimen. The changes from baseline in mean laboratory values that are typically seen with a low-dose LNG/EE cyclic OC [monthly oral contraceptive] were also observed with this continuous OC in a comparative study with a 21-day regimen of LNG 100 μg/EE 20 μg cyclic OC. The overall incidence of AEs [adverse events] associated with this continuous OC, except for a higher rate of events related to uterine bleeding, was consistent with that commonly seen with a low-dose LNG/EE 21-day cyclic OC that includes a 7-day pill-free interval.

    We can reasonable attribute the higher rate of unexpected uterine bleeding to the fact that this regimen attempts to prevent menstruation entirely and sometimes it is not 100% effective.

  • Finally, this regimen is just as effective at actually preventing pregnancy. That is sort of an important part too.
  • Which brings us to the caveats.

  • When breakthrough bleeding occurs in this regimen, it is unpredictable. The higher rate of uterine bleeding did result in a higher discontinuation rate (people not wanting to finish the study) than with normal monthly OCs:

    Discontinuation due to uterine-bleeding-related conditions was the reason for the overall discontinuation rate of 57%, which was higher than that expected with cyclic OCs. The overall discontinuation rate was higher than those of other studies partly because 8.4% of discontinuations were due to sponsor withdrawal from the study even before all subjects could complete the study. The discontinuations for uterine-bleeding-related events with this continuous OC points out the need for studies to investigate the most effective methods to manage irregular bleeding and to reduce discontinuations due to uterine bleeding with this product.

    Although the overall incidence of uterine bleeding, which includes spotting, was higher during the first six pill packs than observed with cyclic OC regimens, it was not a safety concern, as evidenced by the absence of a clinically important change in the hemoglobin and hematocrit levels. AEs attributed to uterine bleeding in this study were not unexpected for this type of regimen. AEs related to uterine bleeding occur more often with extended-cycle regimens than with cyclic regimens, even when subjects with a history of breakthrough bleeding/spotting are excluded in some studies.

    As you can see, although the researchers took about 10% of women out of the study because of bleeds, on the whole they are not concerned because the bleeding that did occur did not cause large reductions in the amount of blood in the women involved. Basically bleeding does happen, but it isn't hemorrhaging.

  • Also, it appears that there is a subset of women for which this regimen is going to be ineffective at preventing bleeding entirely. However, most of these women still report being happier with this regimen than the alternative.

    During the study, the women who experienced uterine bleeding while on a pill pack had minimal changes in the median number of days of bleeding and spotting per pill pack. This was especially apparent after the first few pill packs in those women who initially had bleeding and/or spotting. While the incidence of uterine bleeding decreased with longer use, there remained 21% of subjects with uterine bleeding in Pill Pack 13, with a median of 4 days of bleeding and 3 days of spotting per 28-day pill pack. However, for those women who experienced bleeding on Pill Pack 13, they reported their level of satisfaction with continuous LNG/EE OC on Pill Pack 13 as: satisfied, 77%; neutral, 7%; dissatisfied, 16% (data not shown). This suggests that there is a subset of women who may not achieve amenorrhea with prolonged use of continuous OC. The lack of amenorrheic outcome may lead to the discontinuation of OCs in these women.

    Basically, that is saying that some women are going to try this, and it is not going to work. Some of them are going to be happy because it makes their periods easier. Others are not and are going to stop using it.

What to think about all of this? I think it is an important first step -- both in a scientific and a women's health sense. It would be very interesting to know whether women will be healthier if they have fewer periods in their lifetime. My suspicion is that a great many would certainly be happier if they had fewer.

Would I recommend you go out and try this immediately? Absolutely not. I am not a women's health expert. The decision about what birth control to take is one that you need to make with your doctor. However, it would appear that your options are increasing.

Hat-tip: Eurekalert.

More like this

DAMN! I was born 40 years too late. I'd have jumped at something like this if it had been available. OTOH, at 50+, it's rapidly becoming a moot point. But still.....

By anomalous4 (not verified) on 13 Dec 2006 #permalink

There are several different questions here. Maybe women don't "need" to have as many menstrual periods as most of us have today, but there could be big, big safety differences among the actual means and mechanisms of menstrual regulation. For example, we can also have fewer periods by becoming anorexic and severely underweight, or, paradoxically, by becoming extremely obese. (That's assuming, of course, that the causation goes in the expected direction.)

The anecdotal part: When I was in my early 20s, I experienced 18 consecutive days of moderate to heavy bleeding accompanied by constant, sharp, utterly miserable cramps because of a mis-adjusted BCP dosage. This is all moot for me now as well, but I'd take even the most uncomfortable of natural periods over that experience any time.

I don't know any woman who loves to have periods. Still, to take oral contraceptives all the time...I'm not sure a one year safety study is enough to convince me. What about long term risks? We already know oral contraceptives increase the risk of stroke, particularly as a woman gets older. Women who smoke should not use oral contraceptives. It's a very different thing to have no period because you're pregnant or lactating than to have no period because you're taking oral contraceptives. I wouldn't advise my niece to do it.

This is a really interesting study. I myself have skipped the sugar pills of my OCs (I take Levlen - 150 ug levonorgestrel/30 ug ethinylestradiol) to avoid my period a few times, mainly for convenience (e.g a beach holiday). I've never done it more than once in a row so I don't know the effects that would have, but I know of a friend who used OC pill packs back to back for 6 months without any (observed) ill effects.
I think for some women, especially those trying to avoid pregnancy - having a period is very reassuring as it confirms that you're not pregnant, sort of like a monthly natural pregnancy test.
I'd be interested to know if the long-term effects of this sort of OC usage would be different to normal usage - especially in terms of trying to become pregnant at a later date.

The fact that through most of human evolution women ovulated much less (due to pregancies, breast feeding and shorter lifespans) makes me VERY comfortable taking the pill continually and not having periods (after the first 3 weeks of active pills I start a new pack and toss the fake ones). I have endometriosis and despite 3 surgeries still had to take narcotic painkillers. My ob/gyn and I decided it was not good for me to take them every month. The biggest risk in pill use is blog clots, but I'm willing to take that risk because my aunt died of ovarian cancer and by reducing ovulation I am reducing my risk of that cancer. I also get an ovarian ultrasound once a year at athe ob/gyn visit.

By Texas reader (not verified) on 13 Dec 2006 #permalink

This is interesting...I have turned my periods off not through oral contraceptives but by having a hormonally-based IUD 'installed' a couple of years ago. I've never looked back in regret and have had no complications whatsoever. I thoroughly recommend it to any woman who suffers from horrible periods like I did -- I'm very glad to be rid of my semi-regular hormonal hell.

I am kind of thinking along the same lines as Zuska. I have yet to see what the long term affects will be from taking these pills all the time. We do not really know what long-term elivated estrogen levels in women will do to them as they get older. Periods only three times a year, that sounds great, but I'd be a bit weary to jump on the band wagon before some studies are published showing the effects on women after several years not just one.

I am really pleased to see that people are studying and writing about this. I had been on Depo Provera for about 5 years, and being worried about bone density loss, I was in search of an alternative method that would still stop my periods. I have been taking Ortho Cyclen for a couple months now and skipping the no-pill weeks so I'm continuously on active pills. I had breast tenderness in the beginning, and my cup size became fuller (not necessarily a bad thing!), but otherwise I haven't noticed any ill effects and my period hasn't come back--not even spotting. I too was worried about the health implications, but I have to say that I am very happy not having my period and feel more comfortable with my decision after seeing results from studies like this one.

i want to know if it is ok for me to use contrtaceptive for one month only or should i continue it from the time i begin and do i have to see a doctor to begin using it the one i intend to use is nordet so can u plz help me out in this

By kerlina john (not verified) on 20 Oct 2007 #permalink

I have been taking birth control continuously for about 5 years now and I've had no problems whatsoever. My doctor has told me multiple times that this is okay bc women are fine without periods. Its great not having periods since I've always been in sports and Ialways got very sick for days during that time of the month.

By Stephanie (not verified) on 04 Jan 2012 #permalink