The actor starred as The Bride in Quentin Tarantino’s film in 2003, not long after welcoming son Levon in 2002.
And she revealed that slipping into the form-fitting costume was a little daunting after giving birth.
Speaking on The Graham Norton Show, the 51-year-old said: “I really didn’t want to wear the yellow tracksuit.
“I had just had my son and anyone that has just had a baby is not going to want to wear a skin-tight onesie, they would have a lot of anxiety.”
Thurman — who also has two daughters — said that plenty went into her look for the martial arts film.
“There was a lot of training, a lot of work, and a lot of brilliant costume work (to) recreate the look of Bruce Lee while covering my belly!” she said.
Thurman’s performance in the movie earned her best actress nominations at both the Baftas and the Golden Globes.
She reprised the role of The Bride the following year in Tarantino’s second Kill Bill instalment, Kill Bill: Volume 2.
Thurman had Levon with her former husband Ethan Hawke, and the pair also share daughter Maya, who has followed them into acting.
The star also has a daughter with her former fiancé Arpad Busson.
The Graham Norton Show is on Friday, 4 February on BBC One at 10.35pm and is available on BBC iPlayer.
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