CHICAGO - Female urological patients -- who are growing in number -- prefer to see female urologists, but there aren’t enough of them to meet patient preferences, reports a new Northwestern Medicine study.

“The field has been lacking in gender equality,” said Dr. Sarah Flury, a Northwestern Medicine urologist and senior author of a study in the Journal of Urology. “There is an unmet need.”

Female certified urologists, who are a minority within the field, perform a significantly higher percentage of surgery on women relative to their male colleagues, according to the study.

In particular, female urologists perform a higher proportion of gender-neutral procedures, meaning surgeries which are not specific to men or women, on female patients than male urologists do. Fifty-four percent of patients were female for female urologists versus 32 percent of female patients for male urologists.

For the study, investigators looked at six-month case logs of more than 6,000 certifying urologists from 2003 to 2012, which included more than 1 million cases that were either gender-neutral cases (i.e., they could be performed on either male or female patients) or gender-specific procedure groups. These data represented more than two-thirds of all urologists in the U.S., based on current estimates.

While there have been anecdotal reports of women preferring female urologists, this is believed to be the first study analyzing the influence of surgeon or patient gender on surgical practice patterns.

“Every day in my practice I hear women say, ‘Oh, I’m so glad you’re here. It has taken me a long time to find a woman in this field,’” Flury said. “In some smaller cities, there isn’t a single female urologist.”

One reason more women are seeing urologists is because of incontinence as they age. The stigma has diminished around this condition, Flury said, making women more comfortable to seek help.

The number of female urologists is growing, but they still represent a small portion of the field. Out of about 9,600 urologists in the U.S., only about 8 to 12 percent are women, the study reports.

The number of female urologists has risen from 34 women in 1981 to 512 in 2009. The percentage of female urology residents has grown from 5 percent of the field in 1989 to 23 percent in 2011.

“In many medical specialties there is a discrepancy between men and women in the field, but urology has one of the largest gender disparities,” said lead author Dr. Daniel Oberlin, chief urology resident at Feinberg. “Our study shows a lot of female patients may favor female surgeons. We need to embrace these findings and encourage more women to pursue urology. The misconception is urology tends to deal with male issues, but we deal with the kidneys, bladder and entire urinary tract -- a lot of organs that affect women.”

“We often assume that a physician's training, experience and expertise may influence the type of patients they treat, yet this is the first time we have shown that a surgeon’s gender alone will shape the gender of patients they see in clinic,” Oberlin said.