This is a form of Escapist Fantasy, and is actually quite popular with both men and women. "Conception" (or "impregnation") fantasies are one of the most popular in all corners of the world, so it's no surprise that this pops up in fiction often.
The main difference between the way it's marketed toward gender is that for male audiences, the beauty or sexual desirability of the woman is played up (and domestic compatibility, if any, is just a bonus), while for women, domestic compatibility is emphasized and his handsomeness/hunkiness is the bonus. That binary is part of the reason why, in mainstream media, the person chosen is Always Male and the chooser is Always Female. There's a persistent Stereotype that men simply desire sex while women desire children and domestic stability; thus, in fiction, while male characters tend to be quite fond of the baby-making, only women are as keen on the baby-raising. There's also the fact that this was pretty much standard operation for women throughout most of human history (including present day); a woman being used as nothing more than a tool to have a child is mundanely commonplace.
Further, men have less Body Horror to deal with. The realities of the fantasy involve far less risk for men than for women, what with the whole nine months of inconvenient pregnancy, changes to their body and hormones, then the many hours of painful labor. Stories that focus on titillating female audience typically do something to alleviate or circumvent this dilemma to avoid Fetish Retardant. Another possibility is that idea of taking control of the situation appeals to women. In cultures where arranged marriages are the norm (even in societies where this isn't the case, the cultural shift wasn't that long ago) this idea could be very alluring. Even in a more equal society, there is sometimes an attitude that getting someone pregnant is something a man does to a woman, and thus she is the passive recipient with little choice in the matter.
Although rare, if any coitus happens in the story, it's usually with a conscious effort to breed or make a child. (And we'll leave it at that.) The Grand Finale almost always establishes Babies Ever After. Lastly, a character may have many chosen partners for this (if male, that is—this is highly unlikely if female).
