When Google gathered five woman technologists for a session on female-centric design at Google's IO developer conference, it must have known the panelists would eventually critique Google itself. But the company was probably hoping the designers would stay away from Google's soft underbelly, social networking.

No such luck.

The session, "Designing for the Other Half: Sexy Isn't Always Pink," was a wide-ranging discussion about how largely female communities are kept engaged at sites like pretty-picture hub Pinterest, fashion community Polyvore, and labor marketplace TaskRabbit. But the capacity crowd, composed largely of male programmers, looked up from their laptops when the discussion turned to Google's runner-up social network, Google+.

Why, a male questioner asked the panel, is Google+ such a sausage fest? Recent surveys indicate Google+ is roughly 70 percent male, as compared to a 51/49 split on rival social network Facebook.

The women on the panel honed in on two key problems: the way Google+ works and the people who are on it.

"It probably just needs a [user interface] overhaul," says videogame entrepreneur Margaret Wallace. "It's a UI thing." Wallace says she's a fan of Google+ and uses its video "hangouts" feature extensively, but that the social network's interface reflects the techie roots of the Googlers who built it.

Google, which declined to comment on the gender breakdown of its social network, has a long tradition of using its own products internally before releasing them to the public. Products like Gmail and Google Buzz had lengthy incubation periods inside the company before they were released to the public.

But that internal testing process can lead to products too tailored to the distorted bubble in which Googlers operate, where the food and transportation tends to be free, where the internet is incredibly fast and reliable, and where coworkers tend to be brilliant male computer scientists. Facebook, in contrast, was built by college students, for college students. And Google+ can't yet compete.

Jess Lee, founder of the fashion-photo community Polyvore, also thought Googlers might be to blame for skewing Google+ so male.

"I have one theory, just a theory" Lee says. "I think the seed of that community is very very important. Polyvore was seeded on fashion forums. Google+ was actually seeded with Google employees, so it was tech, and honestly mostly male. That's part of how it grew – those people invited their friends. Facebook started at colleges... Myspace probably started with music. It's all about the seed, and the seed for Google+ was different."

The good news for Google+ is that a social network can overcome its initial seed, at least according to Tracy Chou, an engineer at the product-photo-site Pinterest.

"You have to start somewhere," Chou says, "and if you do well with it you can start figuring out adjacent areas to move into and grow from there. I'm sure when Wikipedia started it was not a comprehensive collection of articles about all topics."

Pinterest is already seeing a shift away from its own seed users, Chou added. The site's audience is largely female in the United States, but as Pinterest expands internationally, starting with Spanish-speaking countries, "the gender split is much more even." If Pinterest can pull off that sort of gender reversal, maybe Google should consider acquiring the blooming social network – and keeping it far, far away from the nerdy male Googleplex.