Feminism in general (with birth control and abortion) changed things quite a bit if we consider it including the rise of women in the workforce. Look at the chart of labor participation. I believe its changes at the time mostly reflect women starting to get jobs.

Although, people could maybe speculate that dual income families also became a necessity as a result of worsening economic conditions. I don't know.

(And for the record, I'm not using feminism as a negative word here.)