Editors at America's Star magazine claim the Raising Hope actress and her boyfriend Edward Owens are starting a family together, even quoting an insider as saying Plimpton "has wanted this for a long time".
But the 41 year old's publicist has dismissed the gossip, telling WENN, "This is completely false. Zero truth to this."
Plimpton has previously described her frustration at being asked about whether she plans to have kids, admitting she's sick of the constant line of questioning.
Last year (11), she told New York magazine, "Oh, God, this subject! You're 40, you're getting old, your ovaries are drying up. The gynaecologist is like, 'So, are you thinking about it?' It's just the question everybody - no offence - feels like they can ask. Like, 'So, what are you going to do with your reproductive organs?'"