CBS head of drama Christina Davis is departing the company, Variety has learned.

Davis, who is currently on maternity leave, has elected to leave CBS following the arrival of twins last month.

Davis has held the position of head of drama for CBS Entertainment since 2007, and first joined the company is 1997 as an assistant.

“My two decades at CBS have been the most rewarding of my life, and I can’t thank Leslie Moonves enough for his leadership and vision,” said Davis. “From my first day as a temporary assistant under Nina Tassler, CBS has given me the tremendous opportunity to work with the most talented and dedicated executives, writers, producers and directors in the entertainment industry. I am also eternally grateful to the drama development team who has been such a critical part of bringing so many amazing series to the network. I’m proud of what we accomplished together and it has been a joy to work with you each and every day. And now, with gratitude for what has gone before, I look forward to new challenges ahead of me, including my expanding family.”

Leslie Moonves, chairman and CEO of CBS Corporation, commented: “Christina is a terrific CBS homegrown success story. She rose through the ranks quickly and enthusiastically, making valuable contributions to our programming every step of the way. We’re grateful for her many years of leadership in drama, proud of her many accomplishments at the network and wish her much success in her next chapter, especially with her growing family.”

Davis began at CBS as an assistant to former network boss Nina Tassler, who at the time was head of drama development. Davis rose through the ranks, ultimately becoming head of that department, and was named EVP of drama development in 2009. Davis has been responsible for helping develop such dramas as the “CSI” and “NCIS” franchises, “Bull,” “MacGyver,” “Blue Bloods,” “Hawaii Five-0,” “Madam Secretary,” “Scorpion,” “Criminal Minds,” “Elementary,” “Code Black” and “The Good Wife.”

Davis’ departure comes as CBS is settling into its new entertainment leadership with Kelly Kahl and Thom Sherman now up top at the network, following the exit of president Glenn Geller, who left the company after suffering a mild heart attack.

Davis’ replacement was not immediately named.