You hurt; he doesn't. Is there a gender when it comes to pain?

Researchers have sought the answer to that question for years, with some speculating that women just verbalize their feelings more, including their perceptions of pain, and others maintaining that women feel pain more intensely for some some reason. Recent studies have produced some interesting results.

A plastic surgeon from Illinois and his colleagues have uncovered a physical difference that might help explain the difference. Women have more nerve fibers, at least in their faces, found Bradon J. Wilhelmi, MD, in a study he published in the journal Plastic and Reconstructive Surgery in October 2005.

"Our study indicates that the density of nerve fibers of the skin in the cheek is higher in women than men," says Dr. Wilhelmi, a plastic surgeon at Southern Illinois University School of Medicine in Springfield. "So you can deduce that women have more sensation than men."

In the study, Dr. Wilhelmi's team cut small samples of skin from the upper cheeks of the cadavers of 10 women and 10 men. Then they used a microscope to count the nerve fibers in a one-square-centimeter area of skin. Women's skin samples contained an average of 34 nerve fibers, and men's had just half that amount: 17. Within the sexes, there was variation too. Women's skin samples contained up to 19 more or 19 fewer than the average, and men's samples contained in the range of eight more to eight fewer than the average.

The clinical relevance? "Maybe we need to be more careful in prescribing medicine for pain and take gender differences into account," says Dr. Wilhelmi. His study results suggest that when a woman has a face-lift or other cosmetic surgery on the face, undergoes dental surgery or maybe even receives Botox injections for wrinkles, she might need more pain medicine than a man.

The study, he says, "lends credibility to patients who have pain that's not as well controlled [as others']." They may have more nerve fibers and thus more sensation.