Of course you feel guilty about working long hours while your little darlings are waiting for you at home. But what about your Big Darling, and how your job affects that relationship? Let's get to the point: We're talking about sex.

Organizational behavior expert Herminia Ibarra tackles this subject in Harvard Business Review's blog. She writes that women often feel compelled to put the brakes on their high-flying careers for the sake of their marriage. She cites an episode in which a senior woman was asked to join a high-level diversity group that focused on women's advancement. When asked about whether she would take a new position that required frequent business travel, this woman made it clear that long absences from home would not work for her. She told the group:

Let me tell you what diversity means to me. My husband told me, "There will be sex in this house at least once a week, whether you are here or not."

I can't imagine most women would be that blunt about why they're turning down a demanding job. (And I hope most men are not quite as crass as that woman's hubby.) But that honesty about sex, Ibarra argues, is what we need to inject into the discussion about work/life balance.

"Relationships with partners are rarely mentioned, except with regard to their role in household and child-rearing duties," Ibarra writes. "A less discussable set of issues—sex, intimacy, the role that partners play in helping each other grow and develop, personally and professionally—is somehow off the table."

Ibarra suggests that women tend to be too tired for sex because they have to juggle so much on the homefront. Ibarra sums up the routine of executive moms :

Get up early, get the kids off to school, go to work, come back for dinner with the family, get the kids to bed, get back online for a few hours, fall into bed exhausted. Repeat again the next day unless traveling. What could get squeezed out of that routine?

Several lawyers I talked to agreed with Ibarra. "It’s the fact that we are raised to put our needs aside and give everything to everyone and never get what we need back—in work and in our personal life," says a senior female lawyer at a Fortune 500 company. And missing out on a fulfilling sex life, she suggests, is one explanation why so many professional women seem to be attracted to a book like Fifty Shades of Grey. "Ask yourself why the entire population of educated women in NYC thinks bad porn is interesting," she says about the best-seller. "The story could not be more trite. Virgin meets handsome businessman with Porsche and S&M room."

Having a decent sex life takes effort, adds a female partner at an Am Law 100 firm. "Before kids, it was manageable for me. With babies and toddlers, it's so much harder if you want to do your work well, and have quality time with your kids and with your husband—including sex." What's required to make it all work, she adds, is "a lot of organization, and even then a lot of flexibility." 

What I find interesting about this whole discussion is that there's a presumption that intimacy suffers when women take on high-pressure careers (the title of the HBR post is "Sex and the Working Mom"). I get that women do more juggling, but wouldn't a couple's sex life suffer too if the man was the one working like a maniac?

Or are men never too tired for sex—or just won't admit it?

Do you have topics you'd like to discuss or tips to share? Email The Careerist's chief blogger, Vivia Chen, at [email protected]