Cause of Gender Confusion is Unclear

WHEN Dr. Lori Kohler was a medical resident in the late 1980s, her instructors never broached the subject of treating transgender patients. She learned nothing about these patients' personal experiences, how to treat them medically or how to put them at ease.

At the start of her career, she was skeptical of people who claimed to be born the wrong sex. Kohler says: "(I thought) What are these people talking about? That's ridiculous."

Since her days as a resident, Kohler has worked with about 200 transgender patients. The experience transformed her attitude.

"There's every variety of person in terms of sexuality," says Kohler, who now trains medical residents at the University of California, San Francisco. "It's really our strict rules that keep people in the boxes we try to keep (them in)."

Kohler is the primary care physician of about 100 transgender patients through UCSF and works with 50 or 60 as a consultant to the California Department of Corrections, which often deals with transgender inmates, particularly male-to-female sex industry workers.

Although she has specialized in treating transgender patients since 1994, the expertise Kohler offers her students bumps up against certain limitations.

Despite a smattering of research conducted around the world, Kohler and other medical experts have not pinpointed what causes people born as one gender to identify more strongly with the opposite sex.

"Medically there is no explanation," Kohler says. "There are lots and lots of theories in the psychology and psychiatry worlds. It's probably much like being gay or lesbian. No one can explain it, it's just something that exists."

Proposed theories

Some theories propose that while in the womb the fetus encounters opposite sex hormones or perhaps a spontaneous genetic mutation occurs during development.

Studies of a part of the brain involved in sexual behavior, conducted at the Netherlands Institute for Brain Research, suggest that this area of the brain -- called the BSTc -- is smaller in women than in men and smaller in male-to-female transsexuals. Physicians working with transgender patients consider the research interesting but not conclusive.

Dr. Sheila Kirk, a member of the San Francisco-based Gay and Lesbian Medical Association, points out that the conclusions of the study were based on an examination of the post-mortem brains of about 10 people, a small sampling by clinical standards.

"This is very preliminary work," says Kirk, who founded the Transgender Surgical and Medical Center in Pittsburgh, Pa., with two fellow surgeons in 1997. In 2000, Kirk retired from the center, which has since closed.

Kirk, who herself underwent genital reassignment surgery -- sometimes called gender confirmation surgery -- to switch from male to female, now lectures and writes about transgender issues.

"We don't know whether (transsexualism) was there at birth," Kirk says. "(Some studies) point somewhat to an interuterine causation for the transgender person."

Aside from identifying as the opposite sex, transgender people don't suffer from a greater incidence of physical or mental health problems than the population at large, Kohler says.

Not explained by science

"There's an experience of themselves that's absolutely not explained by any science," she says. "There are greater struggles people have to deal with being transgender. I think of this more as a social disease."

Estimates suggest that transsexualism occurs in 1 in 11,900 men and in 1 in 30,400 women, according to the Harry Benjamin International Gender Dysphoria Association. The association provides a network for professionals from lawyers to psychologists who work with the transgender community.

Psychologist Bean Robinson, executive director of the Harry Benjamin association, suspects the actual number of transgender people in the population runs much higher. The difficulty of counting this population, short of including a gender question on a census survey, makes it nearly impossible to get an accurate tally, she says.

"It seems to occur in all countries in the world and all times as well," Robinson says. "There's something about it that has to do with our species' psyche."

Whether the cause proves to be biological, psychological or some combination of the two, as Robinson suspects is the case, it's important that transgender people receive compassionate and fair treatment.

"It's important that people don't treat these people as freaks," she says. "They deserve to live, make a living, not be fired from their jobs."