Celebrity pregnancy stories are nothing new, often cropping up in various star-struck publications soon after famous folks marry or merely go public with a relationship.

But lately, there seems to be a rash of “baby bump” tales out there, and I’ve learned several are not true — at least not yet!

† One of the most frequently reported stories is the one proclaiming Jennifer Aniston and her big love, Justin Theroux, are happily awaiting the birth of their first child. While sources close to the “Friends” star tell me Aniston is serious about becoming a mother — and sooner, rather than later — she’s not dating the stork at this point.

† There’s also truth to the rumor that Jennifer Lopez would like to have another child — and likely with her current love, dancer and choreographer Casper Smart, “but that would only be after Jennifer is 100 percent sure their relationship is on solid ground and is going to last,” said a longtime J. Lo insider.

† Finally, while Miley Cyrus is engaged to Liam Hemsworth, a very good Cyrus source tells me the online rumor — spreading like wildfire — that the former “Hannah Montana” star is already expecting “just isn’t true.”

BOOK BEAT: Joan Cusack, her husband Dick Burke, Rev. Jack Wall and Sheila and Chris Kennedy are among the hosts for a book party Wednesday at LuxBar for Burke’s college roommate and Kennedy’s cousin Mark Shriver. The former Maryland state legislator has penned a poignant personal memoir, A Good Man: Rediscovering My Father, Sargent Shriver, about the Peace Corps founding director and former vice presidential candidate who lost his tough battle with Alzheimer’s last year.

ROLE MODELS: Given the Hollywood speculation about how Rob Lowe has maintained his youthful looks, it is interesting that the actor is close to inking a deal to portray Liberace’s plastic surgeon in “Behind the Candelabra,” starring Michael Douglas as the flamboyant entertainer and Matt Damon as his longtime lover, Scott Thorsen.

† Northwestern grad Dermot Mulroney is joining “Jobs,” the independent film starring Ashton Kutcher as the late Apple founder Steve Jobs.

CHANGING HIS MIND: After pilot Doug Gotterba kept his mouth shut for decades — never once blabbing about the rumor he and John Travolta had a six-year affair, when Gotterba was the actor’s private pilot — it seems he’s had a change of heart.

In the wake of so many former Travolta associates going public and chatting about the actor’s sex life — allegedly for pay — Gotterba is doing the same. A tell-all supposedly penned by Gotterba is making the rounds of several publishing houses.

SEEN ON THE SCENE: Yes, that was Conan O’Brien and his loyal sidekick Andy Richter spied leisurely lunching Wednesday at South Branch, before heading to the “Conan” taping at the Chicago Theatre. … Huge animal lover Betty White got all misty-eyed when Todd Temperly, manager of the Palmer House, gifted the actress with one of the hotel’s bone-shaped collar tags for her beloved pooch Pontiac — boldly proclaiming, “I woofed it up at the Palmer House.”

STAGE SET: Woody Harrelson and longtime buddy Frankie Hyman tapped into their experiences working construction in Houston back in 1983 to pen “Bullet for Adolf.” The play goes into previews Off-Broadway in New York next month.