Like many other things in life, pain discriminates by gender. Women, studies show, feel pain more intensely than men, suffer disproportionately from conditions like chronic pain and migraines, and are more likely to be undertreated for pain than men.
More pain, no gain
More than 70 percent of people who report suffering chronic pain are women, according to a 2003 report in the journal Obstetrics and Gynecology Clinics of North America. Compared with men, women are more prone to a wide range of painful conditions, including migraines, irritable bowel syndrome, temporomandibular joint disorder, and fibromyalgia.
Women also appear to feel pain more intensely than men. Lab studies show that if you expose women and men to the same painful situation, such as being exposed to gradually increasing heat, women are usually the first to say ouch. On the plus side, other studies show that women handle pain better than men do. This might be because women have more experience coping with the predictable pains of menstruation and childbirth, and know how to prepare for painful episodes.
Ironically, the half of the population that feels the most pain is also the half that is least likely to get the treatment they need. The National Women's Health Resource Center reports that women with chronic pain often have trouble convincing doctors of the severity of their pain. As a result, they're also more likely than men to have their pain undertreated.
Some may be tempted to write off these differences as attributable to cultural influences. After all, there's no doubt that boys and girls grow up with different outlooks on pain. Girls often feel free to cry over small injuries, while boys feel extra pressure to hold in tears. But the gender gap in pain goes far deeper than culture or upbringing. As recently reported by the American Pain Society, researchers are finding fundamental biological differences in the ways male and female bodies sense and respond to pain. Learning more about these differences can help shed light on the basic nature of pain and may lead to improved treatments for all patients.
Not surprisingly, hormones explain many gender differences in pain. The monthly ebb and flow of female hormones such as estrogen can clearly help fuel migraine headaches, a potentially disabling condition that is three times as common in women as in men. Women are especially vulnerable to migraines during their menstrual periods, when estrogen levels are low. Studies suggest that drops in estrogen can also interfere with the body's ability to control pain. During menstruation, women produce only meager amounts of endorphins, the body's natural pain relievers. When estrogen levels are high -- near the time of ovulation -- women can produce about as many endorphins as men, as reported at the annual meeting of the American Association for the Advancement of Science.
The brain also plays a role in the gender gap. In a small study of patients with irritable bowel syndrome, researchers at the University of California in Los Angeles have found that men and women use different parts of their brain to respond to pain. Scan results showed that women tend to turn on their limbic system, the emotional center of the brain. Men, in contrast, respond to pain with the cognitive or analytical part of their brain. Researchers speculate that these brain differences may reflect ancient gender roles. In the old days, women in pain often needed to protect and comfort their young, a highly emotional job. Meanwhile, injured men were more likely to attack the source of the trouble -- with a spear, if necessary.
Unfortunately for women, an emotional response can make an already painful situation even worse. As reported by the American Pain Society, women are more likely than men to develop anxiety or depression along with their pain. Both anxiety and depression can sharpen feelings of pain while raising the risk of disability.
Men avoid pain treatment
Of course, the cool, calm approach often taken by men has its drawbacks, too. Men are less likely than women to take their pain seriously, according to the National Institutes of Health. Instead of getting treatment, men often just hope their pain will go away -- at least for a while.
A study conducted over 36 months analyzing emergency room visits by more than 32,000 Baltimore men found that there was an increase in male visits immediately following televised sports events. The study, presented in October 2006 at the American College of Emergency Physicians conference, suggests that many men who visited the Baltimore VA Medical Center's emergency room for various illnesses, including chest pain, abdominal pain, shortness of breath, and headaches chose to ignore their pain until they'd finished watching their football, baseball or basketball game.
As doctors learn more about gender differences in pain, both men and women should get more of the relief they need. There's certainly room for improvement. Until attitudes change, women may have to be especially aggressive in getting the right treatment for their pain. Men and women may be wired differently, but in the end, relief should be gender-blind.
National Women's Resource Center. Pain and women's health. June 2005. http://www.healthywomen.org
University of Michigan. Pain and the brain. February 2003. http://www.med.umich.edu/opm/newspage/2003/painbrain.htm
American Pain Society. Sex-related differences in the experiences of pain. January 2000. http://www.ampainsoc.org/pub/bulletin/jan00/upda1.htm
Naliboff, B.D. et al. Sex-related differences in IBS patients: central processing of visceral stimuli. Gastroenterology. 2003 Jun;124(7):1738-47.`
National Institutes of Health. Gender and pain. April 1998. http://painconsortium.nih.gov/genderandpain/summary.htm
Smith, Y.T. et al. Pronociceptive and anitnociceptive effects of estradiol through endogenous opioid neurotransmission in women. J Neurosci. 2006 May 24; 26(21):57777-85.
University of California at Los Angeles. UCLA study reports gender differences in the brains response to pain. November 2003. http://newsroom.ucla.edu/page.asp?id=4685
Campbell, P.F. Relieving endometriosis pain: Why is it so tough? Obstetrics and Gynecology Clinics of North America. March 2003. 30(1): 209-220.
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