Massacre in Dinosaur Valley (1985)
https://www.imdb.com/title/tt0089562
Daughter of famed paleontologist (Suzane Carvalho) and a model on a fashion shoot (Susan Hahn) get captured by primative natives in the Amazon. They are drugged and stripped nude by the natives in preparation of a sacrificial ritual.
Lots of 1980's neatly trimmed pubic hair on display as panties are pulled down.
I edited down the scene to just the good parts.