This is a post by guest blogger Jeff Bussgang.

I find the preponderance of males in VC an annoying and stubborn phenomenon. When I first entered the start-up game as an entrepreneur in the mid 1990s, I didn't think much of the "VC gender gap" as there were plenty of women executives around. In fact, between one third and one half of the executive teams at my two start-ups (Open Market and Upromise) were women.

As the father of a capable, ambitious daughter, perhaps I'm over-sensitive to the issue, but since becoming a VC seven years ago, I find it amazing that only 5-10% of the VC industry is made up of women. Only 25% of all VC partnerships have a single women partner and only 7-8% have more than one women partner. Anecdotally, even fewer women are "management company GPs" as opposed to "employee GPs" - in other words, true owners of VC funds as opposed to deal partners. What other major industry remains 90-95% male-dominated? What's the deal?

An outstanding Kauffman Foundation study, “Gateways of Venture Growth”, analyzes this issue and comes up with some thoughtful but unsurprising conclusions. They point out that the industry remains very clubby, and the lack of female role models creates a self-perpetuating cycle. Professor Myra Hart of Harvard Business School writes, “Women trying to launch or further careers as VCs have fewer first-degree connections with those (men) in positions to hire or promote them.”

Another issue that holds women VCs back is the fact that the academic backgrounds of VCs tend to be in technical areas, such as computer science, engineering and biotechnology where, again, females are in the minority.

In talking to my women VC friends, they reinforced these two major issues, but held out some cause for optimism going forward. Irena Goldenberg of Highland Capital in Europe (an formerly an associate with us at Flybridge Capital before she went to HBS and then Geneva), believes there are more female VCs in life sciences as the medical field has a higher ratio of women to men than, say, engineering. Our senior associate, Robin Lockwood, told me she thinks VC profiles simply lags entrepreneur's profiles. As more women entrepreneurs emerge, more women will become VCs.

Here's a thought-provoking observation that an anonymous woman pointed out to me (and please do not accuse me of channeling Larry Summers on this - I'm just passing along what I heard): she believes the VC industry is male-dominated because men are more wired to take risks than women. Gambling, she points out, is more popular amongst men than women. Thus, risk-taking with capital is more likely to be comfortable for men than women.

Some women have been able to break out as strong investors and industry leaders. In my informal survey, a few experienced women VCs stood out as strong role models: Venetia Kontogouris at Trident Capital, Annie Lamont at Oak, Patricia Nakache at Trinity and Nancy Schoendorf from Mohr Davidow.

I guess when you have a clubby, tightly-woven, self-perpetuating network, it's hard for women to break in. It's a stubborn phenomenon, but I hope we can figure out how to correct it. Otherwise, our industry is tragically losing out on 50% of the world's best talent!

Serial entrepreneur Jeff Bussgang is a partner at venture capital firm Flybridge Capital in Boston.