The 37-year-old Mayer will work from home and continues to lead the company and "is involved in all critical decisions making," a Yahoo spokeswoman said on Monday.

"She will be working remotely and is planning to return to the office as soon as possible (likely in 1-2 weeks)," Yahoo told Reuters in an emailed comment.

Mayer, who was an executive at Google before taking the helm at Yahoo, is the company's third permanent CEO in roughly a year. She is leading an effort to revive the company's flagging revenue growth amid competition from Google Inc, Facebook Inc and a new generation of Web start-ups.

Mayer has yet to brief investors on her plan for Yahoo, but she provided some general details to the company's staff in meetings with employees last week.

Women are significantly underrepresented in the ranks of corporate CEOs, and Mayer's announcement of her pregnancy on the same day that she was named Yahoo CEO garnered widespread attention. Her comments at the time in Fortune magazine that she did not plan to take an extended maternity stoked a debate about whether such an example would help or hurt the cause of other women in the workplace.

News of the birth of Mayer's first child was announced on Twitter by her husband, Zachary Bogue, who wrote: "baby boy Bogue born last night. Mom and baby are doing great-we couldn't be more excited!"

(Editing by Leslie Adler)

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