Pregnant Kate Hudson told David Letterman her doctor thought she was a boy at birth. 

Hudson, who announced her engagement to her unborn baby's father, Muse rocker Matthew Bellamy, on Wednesday 's Today Show, told a cute story about the doctor’s misconception on Wednesday night's Late Show.

“The doctor thought I was a boy,” Hudson said, noting her mother Goldie Hawn loves to tell the story whenever she’s introducing Hudson to someone. “I had a big head ... I was 10 pounds, and I guess when I came out ... I looked masculine ... then they saw the rest of me, and it was definitely not a boy.”