Famed P.R. guru Peggy Siegal began a toast yesterday at what she jokingly proclaimed was her “102nd Birthday Bash” — in fact her 66th — at La Grenouille by introducing her plastic surgeon, Dr. Gerald Imber. The top doc — plus 21 others from fields spanning surgical dermatology, gastroenterology, radiology, gynecology, otorhinolaryngology and more obscure fields — were listed under the heading “Medical Secrets” in a program called, “How To Look Like Me at 102.” The pamphlet with a picture of perfectly preserved Siegal explained further: “Originally Published Six Years Ago, Titled ‘How To Look Like Me at 60.’ ” Imber’s entry in the slim tome said, “His nickname is Ponce de León.” Exercise, beauty and fashion regimens were also included. There was even a hair-transplant specialist “for the boys.” “I’m serious about taking care of yourself,” the hostess explained. “No bread, no alcohol, no desserts.” “No life!” guest Vera Wang called out. Siegal then gave a touching toast to 55 close friends and power players, including Christie Brinkley, Tory Burch, Samantha Boardman, Bob Balaban, Jane Rosenthal, Boaty Boatwright, Stefano Tonchi, Joanna Coles, Danny Strong, Linda Wells, Adam Lindemann and Amalia Dayan. Many of the guests seemed to be between exotic summer vacations in Ibiza and beyond. Art dealer Lindemann said he’s contemplating writing a screenplay in France. Siegal ended by inviting the entire room to a premiere of Woody Allen’s “Blue Jasmine” at MoMA, on Monday. “The movie’s about a Park Avenue wife, played by Cate Blanchett, who gets divorced, loses everything and descends into madness,” she said. “In other words, it’s everybody in this room’s worst nightmare.”