Technically, it's possible to use these terms for any gender. The definition in the dictionary will generally support that, as Max cited. However, there are strong cultural dimensions to these terms.
It has been observed for a while that insults are divided by gender. In a 2011 article entitled "The Name Game: Using Insults to Illustrate the Social Construction of Gender", a researcher talked about a game he had often used in his classrooms. The method was to ask students to come up with all the names they could think of for men and women. The female and male students were also divided during this exercise and wrote their responses on opposite sides of the board.
Some of the findings they came up with: both men and women came up with more insulting names for women than men; men tended to insult women based on sexuality more than they did themselves; and the same sexual behaviour that was an insult when applied to women turned out to be a compliment when applied to men (e.g. slut vs. player). There were various similar findings.
As Catija and P.E.Dant note in comments on another answer, there are other terms that mean something quite different depending on whom they're applied to. "Bitch" as applied to a woman (one of the most common insults) conjures up mean-spiritedness, pettiness, ambition, but applied to a man it implies weakness and subordination. Why does it mean that for men? Because it's associated with women, and terms that seem to diminish masculinity are apparently some of the hardest-hitting. In that article above, most of the male students ranked "homo" (=gay) as the most offensive thing they could be called.
Meanwhile, some terms only seem to be applied to men or women; here is a page from a book that lists some of the differences. You'll notice that on that page, all of the insults for women fall under an analysis of their sexual behaviour. Even terms that semantically appear to be neutral tend to be used for one gender primarily (e.g. high-maintenance for women). Similar lists can be constructed for men, such as this one. Chris H's answer also shows how you can use Ngrams to find "He is a ----" vs. "She is a ----" collocations.
One of the interesting things we find is that terms indicating unapologetic, inconsiderate behaviour seem to cleave most closely to men. Among these are jerk, asshole, dick, douchebag, bastard, prick and, yes, fucker and motherfucker.
From what I recall of my linguistics education, many of these patterns hold true when examined across languages. One of the most reliable phenomena is that terms that simply mean "woman" are pejorative. There are obvious and disheartening societal reasons for this.
Despite these trends, however, the way we use these terms may change someday. Many things are in flux, including gender roles. Perhaps in the same way that terms like "actor" have come to be unisex (instead of "actor/actress"), our insults will become more "egalitarian" too.