Huh? Women used to split wood, walk behind plows, wash clothing in a vat of water boiling over an open fire, hunt big game, etc., etc. - and then go make dinner, change diapers, and all of that stuff as well on top of day of doing that. Sometimes frontier men went through 2 and 3 wives because they essentially got worked to death.

When Federal law required mines to no longer discriminate against women, 30,000 women went into coal mining in the first 10 years. Today, about 40% of entry level jobs in all sorts of mines around the world are held by women. Women were doing construction work in the middle ages - although they were socially considered only slightly better than prostitutes for doing so. Where women have not be very present in those sorts of jobs it's because men have actively prohibited them from having the opportunity. Some of the earliest factory workers were woman, and when men vacated the jobs that required greater strength because they went off to WWII, women built airplanes, and bombs, and everything else. They farmed the land and milked the cows because there was nobody else to do it. And they were quite capable of doing it too.

Acting like women aren't very strong is just absurd cultural myth designed to disempower and hold women back. Hell, giving birth is about the most difficult physical thing a human being can do. Some women did that in rice paddies or fields and then continued working.

I will agree with you that the advent of the hormonal birth control pill did give women the ability to have greater choice about when and how many children they wished to have - something that has been widely recognized as having a tremendous impact on women's economic prospects and status.