Near the beginning of the movie, Gerda says she has her period and on the same evening, she lifts her night gown and is naked underneath!
I bet at that Time they didn't have tampons so shouldn't she be wearing panties and protection underneath?
Women have been using various materials as "tampions" for thousands of years: paper, leaves, even - eek! - wood! I don't think the modern type had been invented at this time, but given some of the sleek and slinky dress styles of the time, I imagine many of the more sophisticated and stylish women such as she had their methods.
Just watched the film, I don't think it was the same day but they did not make that clear.
Either way, tampons were available from the 1920s.
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