This is one of the many, many Bergman films she appeared in.
As noted in the comments, her breasts were bigger in this film than in any other topless appearance. It seems that she was either pregnant or had recently given birth.
Quick nudography:
My Sister, My Love (1966)
The Girls (1968)
The Touch (1971)
En Dares Forsvarstal (1976, TV)
Goodness! Haven’t seen this film and didn’t know she ever had those. It looks like her only child was born around ’71, so I’m guessing she was lactating during filming. I definitely don’t recall her bust being that impressive in her earlier Bergman films.