Arquette and her husband, actor David Arquette, have spoken publicly about their struggles to have children. The two recently said they were trying to conceive via in-vitro fertilization.
"Yes, we are confirming they are expecting," said the actress's publicist, Nanci Ryder, who declined to provide any other details.
The 39-year-old actress and her husband, 32, were married in June 1999.
This is the second co-production for the couple. The two are also producing a new 30-minute show called "Mix It Up," which follows a housing makeover for roommates who are stylistically at odds.
Arquette got her first big break as a teenage dancer in a Bruce Springsteen video and later honed her sitcom skills as Michael J. Fox's girlfriend on "Family Ties." She is now in her 10th and last season as the obsessive cook Monica Geller on "Friends," with this year's episodes following her and TV husband Chandler Bing's efforts to adopt a child.