Women are almost as likely as men to fill the seats of medical school and law school classrooms, but business schools have made less progress in boosting female enrolment, which is stuck at 32 per cent.
Enrolments at full-time MBA programmes have not risen above this in the past decade, figures compiled by AACSB International, which accredits B-schools worldwide, show.
"There's a frustration on the part of a lot of women, and probably men, too, that we haven't made more progress," says Dr Amy Hillman, dean at Arizona State University's W.P. Carey School of Business.
Last August in the United States, the White House convened 150 leaders from top business schools and had them sign a pledge to take steps to boost female enrolment by cultivating potential applicants early on in their education and by offering more financial aid.
"When business schools are missing out on a large share of female college graduates, they are missing out on an extremely large share of the top qualified college graduates," says Dr Betsey Stevenson, a University of Michigan economist who helped lead the August summit. "If they want to continue to be a relevant part of the training in the 21st century, they are going to have to make changes that will make them more attractive to women."
Deans say business schools suffer from a unique timing problem. Unlike law and medical schools, which tend to enrol students soon after they finish college, the full-time MBA programme is designed for people who have already proved themselves professionally.
Elite B-schools typically prefer that applicants have about five years of work experience, which means the average MBA student is 30 years old at graduation, Bloomberg data show. Women in their late 20s who think they will want to have children at some point may feel they'd do better racking up career experience than taking two years off for business school. Dr Hillman says: "You've got some prime childbearing years and prime career trajectory years, and I think we are seeing women who are not willing to come out of (the workforce)."
There is evidence lowering the work experience requirement for applicants makes classes more female. George Washington University School of Business mandates a minimum of two years and 41 per cent of its MBA students are women.
Also, the same share of women and men enrol in specialised business master's programmes, such as accounting and marketing, which often do not require any on-the-job experience, according to AACSB.
Dr Sarah Fisher Gardial, dean at the University of Iowa's Tippie College of Business, says: "If we decide to let women go straight through (to business school after college) and lower that bar, there's no question that we would get more women in." But at what cost? She and some other deans argue that awarding the degree to younger students would make it less valuable. Students, they say, learn more when everyone in the classroom brings his or her work history to bear.
Women may also have trouble seeing themselves at business school because the classes are overwhelmingly led by male professors.
The pledge signed by the 47 schools in August also committed them to try to boost the number of women instructors.
Finance professor Bhagwan Chowdhry from the University of California at Los Angeles's Anderson School of Business has argued that because of the limited number of women PhDs in economics fields, a mandate to hire more women professors could end up lowering the calibre of faculty.
Anderson's dean Judy Olian, who says she's made hiring women professors a priority, counters: "If anything, our standards have risen."
To tempt women to take time out from their careers to pursue an MBA, elite business schools have ratcheted up the amount of aid targeted to female applicants. Last year, 36 MBA programmes affiliated with the Forte Foundation, a consortium of B-schools and corporations that promotes the advancement of women in business, awarded US$18.5 million (S$25 million) in scholarships to women, up from US$5.6 million in 2010.
"There is no better time to apply to an MBA programme for a woman," says dean Idalene Kesner of Indiana University's Kelley School of Business. When her daughter, 26, mentioned she was thinking about business school, she advised her to pounce. "My advice is, 'Think now, think fast.'"