In a 1999 essay on reasons for the male predominance in computer science, applied mathematician Dianne P. O’Leary wrote: .

Suggestive pictures used in lectures on image processing … convey the message that the lecturer caters to the males only. For example, it is amazing that the “Lena” pin-up image is still used as an example in courses and published as a test image in journals today.

https://en.wikipedia.org/wiki/Lenna#Criticism

That’s 25 years ago…