Some quick statistics for you
A lot of the time when people complain about mpreg they complain about how prevalent it is. However I wanted to show ya’ll some quick numbers, since our perception of somethings prevalence is deeply subjective.Â
(All of these numbers were collected via the search bar on AO3 as of this morning (April 25, 2016). They do not take into account mistagged or untagged fics. The only exclusions made in any search are those that are mentioned with the numbers.)
On AO3 there are 2,247,808Â fics. Of those fics 19,591Â are tagged Mpreg. That means that 0.87% of fics on AO3 are tagged Mpreg.Â
However when we discuss mpreg we generally only mean in fics marked M/M since there are very few F/M and even fewer F/F (in fact I didn’t even check, are there mpreg fics marked F/F?). So if we cut down to only M/M fics then there are 1,589,144 fics (which is 71% of fics on AO3) and  only 18,548 of those fics are tagged mpreg. That means that 1.17% of M/M tagged fics are also tagged mpreg.Â
But that doesn’t give us a good basis of comparison so I did a few other unrelated tag percentages to give us a grounds for comparison. Coffee Shops AUs account for 0.14% (3223 fics) of all fics on AO3. Fake relationship AUs come in even smaller at 0.056% (1269 fics). These however have much more specific guidelines than Mpreg so lets widen our comparison again. There are 308,065 fics marked Fluff. That’s 14% of all the fics on AO3. A more direct comparison would be fics marked PWP. Here we have a tag that like mpregs has very loose guidelines, and a smaller audience than all of general fandom. there are 28,555 fics tagged for PWP making it 1.3% of fics.Â
So really when we say mpreg is too prevalent in fic we are talking about a trope that is between 0.87-1.17% of all fics.  There are 2,228,217 non-mpreg fics on AO3. So if you don’t like mpreg, you have PLENTY of other options of fics to read. Please stop complaining that there is too much mpreg.
Oh! and by the way only 62% of fics tagged for pregnancy are also tagged mpreg. While this might seem high, please take into consideration that 71% of all fanfics are marked M/M. So it seems to me at least that the high prevalence of mpreg fic compared to pregnancy fics is just a symptom of fandoms preference for M/M over F/M or F/F.
Mpreg only accounts for 0.87% of all fanfiction on AO3.  When we look at the numbers we see that mpreg is not that prevalent in fanfiction, it’s just more popular than highly structured AUs (Coffee Shop or Fake relationship ranking in at .014% and 0.056% prospectively). That leaves 2,228,217 fics on AO3 that are not mpreg. If you don’t like mpreg please read one of those fics instead.