“Women, how do they become worthy? … by watching over the men” (Berachot 17a).
“Women” is the will to receive, which is regarded as Lo Lishma [not for Her sake]. What merit does one have if he is working Lo Lishma? The thing is, as our sages said, “A thousand walk into a room and one comes out to teach.” In order for the one to come out to teach, meaning Lishma, a thousand Lo Lishma must assist.
It follows that women, those who are Lo Lishma, because they watch over the men, and a man means bestowing, it follows that they have a part in what they bestowed, in that through him, Lishma came forth.