Although we may not know why so many actresses go for overblown breast implants, one thing’s for sure: Pamela Anderson started it all. Back in the 1990s, the Baywatch actress set a record for bulging porn-star boobs, and celebrities have been copying her buxom look ever since. But as any gossip-column reader knows, big breasts on skinny women don’t always look genuine — or even like a good fake. Here, board-certified Beverly Hills plastic surgeon Dr. Renato Calabria (who has not treated any of these stars) weighs in on some of the worst boob jobs in the entertainment business.

VICTORIA BECKHAM
Grade: C

Let’s be honest: The former Posh Spice has breasts that look like her husband David’s soccer balls. We don’t know her motto, but we think a good one might be “If you haven't got it, fake it!” Says Dr. Calabria, “When you see a very thin person like Victoria Beckham with the round look, it’s a clear-cut sign that they’ve had implants. She is a C, but for her a B would be enough. She’s very thin and doesn’t have a lot of breast tissue."

TORI SPELLING
Grade: D

A boob job? Tori? Really? Tori Spelling’s never publicly admitted that she has bogus breasts, but there were jokes about the rumors in her 2006 TV show So NoTORIous. While her two recent pregnancies can explain why her breasts are bigger, the roundness of her D cups is indicative of implants, according to Dr. Calabria. “She’s too top heavy,” he says.

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TARA REID
Grade: B+

The party girl’s breast implant trauma became public knowledge when she accidentally slipped out of her dress at Sean "P Diddy" Comb’s birthday party, revealing her terrible surgery scars. Afterward, the American Pie veteran said that if she had a chance to do it over again, "I never would have done it in the first place.” Appearing on the TV show The View, she said, “I asked for big Bs, and he did not give me big Bs. He gave me Cs.” Tara has since had a second surgery to fix the first job. But she will always be known for her embarrassing nipple flash. Luckily, when clothed, “Her cleavage looks natural, but the issue is with the scarring,” says Dr. Calabria.

PAULA ABDUL
Grade: C

It’s a good thing that the ex-American Idol star Paula Abdul doesn’t have anyone judging her (alleged ) boob job, because as it wouldn’t get a good review! “There’s too much roundness on top. Natural breasts have more of a slope,” explains Dr. Calabria, who thinks that the 5’2” singer opted for implants that were too big for her tiny frame. “She should have gone a little smaller. She looks to be a C, which [is] too large for her figure.”