Hayden PanettiereSplash News

Whoa, mama!

Hayden Panettiere flaunted her sizable baby bump in a bright ruffled bikini while vacationing in Hawaii over the weekend.

With her hair in a top knot, the 25-year-old had that mom-to-be glow.

Although she and fiancé Wladimir Klitschko have yet to announce her due date, which can’t be far off judging by this photo, the “Nashville” star said she’s gained 40 pounds during her pregnancy.

“And the worst part is that my feet are still size five and they’re going, ‘What’s going on with all this weight?’ They’re about to snap from underneath me with the strain,” said the 5-foot-2 actress, who earlier this month estimated her weight to be 145 pounds.

“I’m still quite muscular, so if you’re running around carrying 40 pounds of extra weight, you’re going to build extra muscle,” she said.