Can a mentor help you balance work and family?

October 4, 2012, 5:34 PM UTC

FORTUNE — Dear Annie: Your article about the importance of mentors and sponsors made me wonder about something that’s happening in my own career, and probably lots of other women’s, too. After three years at a large Wall Street firm, I got laid off in 2008 and decided to take the opportunity to get an MBA. Toward the end of my studies, I also had a child, and am now expecting a second one. For the past six months, I’ve been working in a great job at a global financial services company, where I have two mentors (both female) who have given me some invaluable advice and guidance.

But here’s the thing. Either mentor would make a great sponsor, but I have gotten the impression that, because they both got where they are by putting in nonstop hours (including a lot of travel), they’re skeptical about anyone’s chances who can’t or won’t do the same. Since I’ll soon have two very young children, I’m worried about ending up on the “mommy track” here. I intend to keep being a top performer, but will the need for a bit of flexibility in my schedule — starting with a short maternity leave — put me on the sidelines? Any thoughts? — Just Lisa

Dear JL: Complicated question! It sounds as if both your current mentors belong to the 27% of executive women who, according to a new poll by Citi and LinkedIn, don’t include kids in their definition of success — and hence may indeed see combining a high-powered career with having a family as impractical.

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Carolyn Hughes, whose title is vice president of people at Sunnyvale, Calif., job site Simply Hired, puts it bluntly: “The No. 1 thing holding most women back in the workforce is the need for flexibility. Like it or not, ‘face time’ is still one of the main criteria for advancement in many companies. Women managers rarely challenge that, because talking about it just highlights their need to be out of the office more.”

Hughes, who has two small children herself, points out that technology now makes it possible for many people to work effectively from anywhere. “Thought leadership and creativity can happen no matter where you’re located at any given moment,” she notes. Still, to executives like your two mentors, proving that may take some doing. Here are three suggestions for keeping your career moving forward:

1. Deliver great results. Hughes says you can turn a (possibly skeptical) mentor into a sponsor by doing outstanding work. “I refer to sponsors as champions, and one of the things they do is champion you by defending your ability to handle multiple responsibilities,” she says. “You earn that by showing you can produce terrific results. Once you’ve done that, proving that flexibility can work, resistance to it usually dies down.”

2. Reach out to more mentors. It might help if you could find another female mentor at your company who has succeeded at both raising children and rising through the ranks. But whether or not there is such a person, don’t overlook men. “Most senior decision-makers in big companies are still men, so asking for their point of view and advice is smart,” says Elena Bajic, CEO of Ivy Exec, a Manhattan-based career site and job board for high achievers.

You might even think about finding a mentor outside your own company. Ivy Exec recently launched a mentor network that matches senior executives across a range of industries with high-potential mentees working elsewhere. “Sometimes people need advice on topics they’re just not comfortable discussing with higher-ups at their own companies,” Bajic notes. “Job search strategies, or possible career changes, fall into this category. The best way to make your case for flexibility — and especially how to argue for it in a way that male executives will relate to — might be one of those sensitive subjects, too.”

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3. Have a reliable support system in place at home. And make sure your bosses, mentors, and potential sponsors know you have it. Carolyn Hughes observes that senior executive women like Yahoo (YHOO) chief (and new mom) Marissa Mayer have “round-the-clock backup at home — nannies, housekeepers, a whole lot of help they can rely on when they just can’t be there. It’s expensive and complicated, but you need to build that support on the domestic front while you’re getting ready to move up in your career.”

One further thought: Claire Farley, who was promoted to president of North American oil and gas exploration at Texaco (since merged with Chevron (CVX)) in her late 30s, and who is now a managing director at KKR (KKR), says that turning a mentor into a sponsor may just take time.

“In your first 10 years or so, in any career, being really good at your job is paramount,” she says. “Sponsorship generally happens after you’ve put in 10 or 15 years as a proven contributor, once you’ve started paying attention to different leadership styles and figured out where you want to go.” Coincidentally, 10 or 15 years is just about the length of time it takes for tiny kids to grow into bigger, somewhat more self-sufficient ones. Good luck.

Talkback: If you’ve kept your career moving forward despite working flexible hours to accommodate a family, how have you done it? Were mentors or sponsors helpful? Leave a comment below.