Perhaps not, but "they" might as well have been. She was absolutely no "dumb blonde". Although the number I heard was 150 — never have seen any authoritative documentation on this (and I ain't going to try looking for it!)
“Jayne also possessed an IQ of 163 and was known as one of the most friendliest, as well as publicity loving, stars of the era. She was one of the first sex symbols to ever own a sexual image as well as have a family.”
just googled and found this on Jayne Mansfield, but I have seen it as high as 165.