Yahoo CEO Marissa Mayer is pregnant and expecting twins with her husband, Zachary Bogue Credit: Cindy Ord/Getty Images

It'll be a busy year! Marissa Mayer is pregnant and expecting identical twin girls with her husband, Zachary Bogue. The Yahoo CEO announced the news via Tumblr on Tuesday, Sept. 1.

"The twins part was quite a surprise, because I have no family history of twins or any other predisposing factors," Mayer, 40, explained on her Tumblr page. "However, as I’ve now learned, identical twins occur by random chance in roughly 1 out of approximately every 300 pregnancies. Zack and I have embraced the surprise and are very excited about these new additions to our family."

Mayer and the lawyer, 39, tied the knot in 2009 and reside in San Francisco with their 2-year-old son, Macallister. Like her first pregnancy, she doesn't plan on slowing down when it comes to her workload. (The former Google executive joined Yahoo in July 2012.)

"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," Mayer continued. "I’ve shared the news and my plans with Yahoo’s Board of Directors and my executive team, and they are incredibly supportive and happy for me. I want to thank them for all of their encouragement as well as their offers of help and continued support."

Mayer is over the moon about the next chapter - both personally and professionally. "Moving forward, there will be a lot to do for both my family and for Yahoo; both will require hard work and thoughtful prioritization," she wrote Tuesday. "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."

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