If we take into account the percentage of female sci-fi writers compared to male sci-fi writers as taken from here (http://en.wikipedia.org/wiki/Women_in_speculative_fiction), we get that there are roughly 1.7 times as many male as female authors, so the total presented means that, on average, 1.3 times as many reviews are of male novels as female novels.

So female authors make up about a third of all science fiction writing and get about two fifths of all science fiction coverage which means that, on average, every female author individually gets more attention and mention than her male peer.