Don’t you hate it when everyone and their grandma piles onto a media story and dissects it to death? Yeah, me too, but in this case I really couldn’t help myself.The media is all abuzz about Marissa Mayer’s appointment as the new CEO of Yahoo!, and even more so with the news that she’s also pregnant with her first child. And it was a particular quote from Mayer in a Fortune blog post that needled me: “My maternity leave will be a few weeks long and I’ll work throughout it.”As a working mother of a 1-year-old, I have plenty of thoughts about attempting to work while riding the wave of postpartum hormones, but I’ll leave that to the mommy bloggers. As a communicator and employee advocate, I immediately thought of Yahoo! employees. What message does it send to your people, both male and female, when you indicate that you value work so much that you can’t take a little time to take care of your health and celebrate one of the most momentous occasions in life?On the one hand, it says you’re committed to your job 100 percent. For that, I say “right on.” We all want to follow a leader who’s dedicated and driven. On the other hand, you may have also planted the seed that “real” maternity leave is for wimps; or that to get ahead and be successful in your company, you need to be willing to sacrifice everything; or that you already have doubts that your team will be able to manage without you.The point I’m trying to make is this: Culture starts at the top. What leaders say and the behaviors they demonstrate filter down to the rest of the organization. A culture built around the presumption that work trumps all simply isn’t healthy.Lesson number two: She may think she’s only speaking for herself, but as one of the most visible women in the tech industry, she’s a role model to many. Leaders and communicators should think in advance about how their words will be received by different audiences.Final word: Marissa, if you figure out how to make sound executive decisions while extremely sleep-deprived and hormone-addled, please share your secrets with the rest of us!