Marissa Mayer — the first woman to give birth while running of a Fortune 500 company — is about to make history once again. The Yahoo president and CEO announced on Tumblr last night that she's expecting twin girls some time in December. Juggling a billion-dollar business with three kids under the age of three — that has to be a first, too, right? Along with the happy announcement, Mayer also made it clear that she's planning to take a short maternity leave after her girls are born. "Since my pregnancy has been healthy and uncomplicated and since this is a unique time in Yahoo’s transformation, I plan to approach the pregnancy and delivery as I did with my son three years ago, taking limited time away and working throughout," she writes. While mothers at Yahoo are entitled to 16 weeks of paid maternity leave (a number that Mayer doubled in 2013, also adding eight weeks of paid paternity leave to the company's policy), Mayer opted to only take two weeks after the birth of her son. Some people found this move inspiring. Others felt like it set an unfair standard for women who might not have the same kind of support system in place that a successful CEO has — or the authority to install a nursery next to their office. Regardless of how you feel about her personal choices, we can all agree that Mayer is in the lucky position to decide how much time is right for her and her family, as well as her other "baby," Yahoo. Mayer concluded in her post: Moving forward, there will be a lot to do for both my family and for Yahoo; both will require hard work and thoughtful prioritization. However, I’m extremely energized by and dedicated to both my family and Yahoo and will do all that is necessary and more to help both thrive. The future looks extremely bright on both fronts.