The nanny in the Mayer household is about to get a lot busier. Yahoo CEO Marissa Mayer announced on her blog Tuesday that she is five months pregnant with twin girls. She also noted she plans to keep on working through her pregnancy and will take only a short time off.

Yahoo CEO Marissa Mayer Expecting Twins

Marissa Mayer also added that the doctors tell her that the twins are due close to the end of the year.

Mayer wrote: “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 say: “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.”

Of note, Mayer had her first child (a son) just three months after she took over as CEO at Yahoo in 2012. She was criticized for for her relatively short maternity leave at the time and led to a public discussion about the impact of her decision on working mothers.

Marissa Mayer and other recent controversies have led to expansion of parental leave policies

Given the controversy over her short parental leave, it’s not too surprising that CEO Marissa Mayer expanded Yahoo’s parental leave policy to 16 weeks of paid leave for mothers and eight weeks for fathers. Yahoo now also throws in an extra $500 to spend on child-related expenses including laundry, housecleaning, food or child care.

A number of companies have recently introduced new maternity and paternity leave policies, with Netflix now shockingly offering up to a year of paid leave to parents, a move analysts say may lead to a “baby benefits arms race” with other tech firms as they rush to improve their parental leave benefits to attract and keep top talent.

Others have pointed out that the new Netflix policy could lead to the loss of 10-40% of the time (based on one to four children) of an employee over a decade, which could have significant long-term consequences on labor costs.