Yahoo CEO Marissa Mayer reveals she's expecting twin girls

/ Source: TODAY

Congratulations are in order for Yahoo's CEO Marissa Mayer and husband Zachary Bogue — times two!

"With great happiness, Zack and I have some exciting news to share — I’m pregnant!" she wrote in a post on Tumblr. "In fact, I’m expecting identical twin girls, likely arriving in December."

This is Mayer's second pregnancy since taking the lead with Yahoo. She gave birth to son Macallister in 2012, just months after being named CEO.

MORE: Marissa Mayer says being mom and CEO 'takes a lot of focus'

NEW YORK, NY - APRIL 27: Yahoo CEO Marissa Mayer attends the 2015 Yahoo Digital Content NewFronts at Avery Fisher Hall on April 27, 2015 in New York City. (Photo by Cindy Ord/Getty Images for Yahoo)Cindy Ord

"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 went on to explain. "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."

That same decision to devote herself to her work while also devoting herself to motherhood sparked a national conversation during Mayer's first pregnancy.

In 2012, she worked throughout her two-week maternity leave, leading many to question the demands put upon on working mothers.

In April of the following year, Mayer overhauled Yahoo's parental leave policies, granting mothers up to 16 weeks of paid leave with benefits and fathers up to eight weeks.

Now she's looking forward to the future, both personally, as the soon-to-be mom of two daughters, and professionally.

"I’m blessed to have experienced some of my most extraordinary and proudest personal moments while being Yahoo’s CEO," Mayer added. "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."

We wish her and her growing family the best!

Follow Ree Hines on Twitter and Google+.