Technically... one could ask from a more broader perspective then pru urevu, for any positive Mitzvah which the man is commanded, is the woman's role in aiding the husband of a secondary nature?
A man is commanded to procreate Mishna Yevamos 61b.
But that does not mean a woman doesn't get equal schar
Firstly, a man and his wife are on the same side as Rav Yosef Chaim sonnenfeld said in the artscroll biography about him : In spite of my infererior merit at least my wife can bring me through her account to Olam haba. (Translation from Yiddish). The source of this seems to be the plain interpretation of being one flesh as stated in Bereishis 2 and quoted many times in the Talmud as Ishto kegufo.
Secondly Our Rabbis taught in Brachos 17a:
Greater is the assurance made by the Holy One, blessed be He, to women, than to men; for it says,(Yishaya 32,9) “Rise up, you women of leisure; listen to My voice....” How do women earn [equivalent] merit? By bringing their children to the Beit HaMidrash and to the synagogue, and by waiting for their husbands to return from the Bais hamedrash.
From here we see that even though women don't learn Torah they get just as much schar by making it possible for their husbands to learn, how much more so when they are going through pain to help their husbands procreate.(even though child birth pain is a punishment to Chava and future generations for eating from the fruit of knoledge (Bereishis 2) she is still helping her husband have children and should get equivalent schar).
So yes thank your wife for her input in giving birth which by no doubt is a tremendous zechus for both of you. Even if a woman is separated from her husband she gets equivalent schar for herself.