Yahoo chief executive Marissa Mayer has announced that she is due to give birth to twins – but plans to take little time off and "work throughout".
Ms Mayer, who has led the internet search giant for three years, previously took just a couple of weeks off after giving birth to her first child in 2012.
She announced her latest pregnancy in a blog post saying she and husband Zachary Bogue had some "exciting news" to share.
Ms Mayer wrote: "I'm expecting identical twin girls, likely arriving in December. The twins part was quite a surprise, because I have no family history of twins or any other predisposing factors.
"Zack and I have embraced the surprise and are very excited about these new additions to our family.
"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.
"I'm blessed to have experienced some of my most extraordinary and proudest personal moments while being Yahoo's CEO.
"Moving forward, there will be a lot to do for both my family and for Yahoo; both will require hard work and thoughtful prioritisation.
"However, I'm extremely energised 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."
Yahoo said: "At the company, we are extremely happy for her and supportive of her plans and approach."
In July, the firm swung to a second quarter net loss of 22 million US dollars (£14 million) compared to earnings of 270 million US dollars (£176 million) in the same period a year before.
But Ms Mayer hailed strong revenue growth and said the transformation of Yahoo "continues to make great progress" after boosting the proportion of its income that comes from mobile devices and adding new features to Yahoo Mail.
She is the latest high-flying female executive to make a public announcement about her maternity plans.
Laura Wade-Gery, the Marks & Spencer executive in charge of the retailer's 870 stores and website, said she was going on leave from this month to have a baby.
The 50-year-old, seen as a possible successor to M&S boss Marc Bolland, said in a stock market announcement that she would return to work in January.
Ms Mayer is 40.