It’s Not Just PMS: Pain and the Menstrual Cycle

Because hormones play such a key role in pain reception and perception, women’s pain—chronic or otherwise—is inextricably tied to the menstrual cycle. And where gender bias is present, this provides another excuse to minimize women’s pain.
Most sex-differentiated pain conditions appear during or after puberty. As a girl’s body matures, levels of estrogen and other sex hormones soar, and the menstrual cycle begins. These hormones act on a number of sites in both the central and peripheral nervous systems and in both reproductive and nonreproductive tissues. It is around this time that things like ischemic migraine headaches, irritable bowel syndrome, chronic constipation, chronic tension headache, and other issues come to light in their uniquely female expressions.8
Also, as we know, women have a greater Also, as we know, women have a greater prevalence of chronic pain disorders, migraine, and autoimmune diseases. Falling estrogen levels in the premenstrual period are associated with “flares” of these disorders. Areas of the brain that control perception of pain have receptors for estrogens, as well as for androgens like testosterone, dihydrotestosterone (DHT), and dihydroepiandosterone (DHEA). Estradiol, a form of estrogen, is particularly involved in signal transmission in the central nervous system. When its levels fluctuate, as they do naturally during a woman’s menstrual cycle, susceptibility to and perception of pain can change as well. Therefore, when women at a certain point in their menstrual cycle have a “flare” of their pain disorder, their pain—the way their central nervous system perceives sensation—is actually increased. It’s not a matter of perception. It’s a matter of neural reception.9
The interactions of hormones with the CNS and neuroendocrine systems are well documented, as are the places in a woman’s cycle where breakthrough episodes are common. However, when these women go to the ED or to their doctors, they’re not likely to be asked questions like, “Where are you in your menstrual cycle?” Or “Have you noticed that you tend to get these migraines a week or so before your period?” Instead, they may be given medications or treatments that they may not need for the other three weeks out of the month. However, a provider who is aware of the link between menstrual cycles and pain may be less likely to offer treatment that will help during the few days of this flare; instead, women might receive that age-old brush-off: “It’s just PMS. Wait a few days and you’ll be fine.”
To most people (including many women), PMS is just a part of life, something women have to live with. It’s almost regarded as the price we pay for being women, a normal rite of passage that just happens to be worse for some women than for others.
It’s true, PMS is a part of life as a biological female—but for some women, especially those with chronic pain disorders, it’s an uncomfortable, even excruciating part. So why aren’t we talking about it as a genuine, valid health complaint and seeking out ways to make it tolerable?
Not to sound glib, but if men had to undergo a cycle of testicular pain every month, you bet there would be validation, research, and new meds produced for them. Just like erectile dysfunction became “ED” and got its own sleek blue pill, men’s monthly testicular pain would get an acronym (MTP!) and a designer pharmaceutical solution, along with support groups, television ads—the works. (Okay, maybe that’s a bit over the top. But you can bet that monthly pain cycles wouldn’t be something men “just had to live with.”)
And yet pain flares associated with women’s menstrual cycles are invalidated on a daily basis. Even if tests are performed to look for other potential causes for the pain, providers aren’t always able to help women understand what’s going on (likely because they aren’t aware of the estradiol/pain link themselves), and so women’s concerns are sidelined. Not only does this fail to help women in the moment, but if they feel like their doctors think they’re exaggerating when they say, “It hurts,” the likelihood that they will seek appropriate care in the future is significantly decreased.
While the link between estradiol and pain levels is understood, there are still many questions about how hormonal levels and fluctuations actually impact women’s experience of pain. We know that it happens, but we aren’t entirely certain why.
Two brain-imaging studies looked at whether differences in pain sensitivity in healthy women could be visually measured.10 In one, painful heat was applied to the skin over the left masseter muscle (the muscle that connects the lower jaw to the cheekbone and facilitates the action of chewing). The pain response was measured at two points in women’s cycles: once during a period of high estrogen and again during a period of low estrogen. While there was no significant difference in pain ratings between the two points, different activation patterns were observed in the brain. In another study, a finger was immersed in painfully hot water during low- and high-estrogen points in the subject’s cycles. Here, as well, differences in brain activation were observed, but this time there were also differences in pain and “pain unpleasantness” ratings. This revealed that while hormone levels may or may not alter the neurotransmission aspect of certain kinds of pain, they do affect the person’s perception and experience of pain—and that alteration is statistically measurable via brain scan.
What does this mean for women in pain? To me, it’s evidence that we need to be looking at all this information a lot more closely. Whether it’s a matter of reception, perception, or both, women’s hormonal cycles can and do affect their experience of both acute and chronic pain. And as we learned in Chapter 4, hormone levels also affect the efficacy of pharmaceuticals, including pain relievers. Therefore, women’s unique and fluctuating hormonal states should be taken into account whenever pain diagnoses and treatments are relevant.
Of course, this discussion of hormone levels must also affect peri- and postmenopausal women. As we know, falling estrogen levels create elevated pain states and pain perceptions; therefore, we can assume that permanent changes in hormone levels and cycles will also create changes in pain states and pain perception. (We’ll explore this further in Chapter 7.) More study is needed to understand how menopause affects women’s pain and pain sensitivity, but given what we now know, we should take this into account when treating older women.
Once we understand more completely how the menstrual cycle affects the central nervous system and pain perception in a holistic way, we will be able to more effectively treat pain based on where a woman is in her cycle and stage of life. Until then, we need to keep learning—but also keep listening, regardless of whether a woman’s experience of pain agrees with our preconceptions.

References:

  • Table 2 in Greenspan et al., “Studying Sex and Gender Differences in Pain and Analgesia.”
  • JoAnn V. Pinkerton, MD, Christine J. Guico-Pabia, MD, MBA, and Hugh S. Taylor, MD, “Menstrual Cycle–Related Exacerbation of Disease,” American Journal of Obstetrics and Gynecology 202, no. 3 (2010): 221–231. doi: 10.1016/j.ajog.2009.07.061.
  • Katy Vincent and Irene Tracey, “Hormones and Their Interaction with the Pain Experience,” Pain Reviews 2, no. 2 (2008): 20–24. doi: 10.1177/204946370800200206.

Related Articles

LEAVE A REPLY

Please enter your comment!
Please enter your name here

Stay Connected

21,993FansLike
0FollowersFollow
0SubscribersSubscribe
- Advertisement -

Latest Articles