Sure, they're both the means of your mean-spirited pranks and targets of your amusement, but midget, amputee, and pregnancy porn are all fairly nichey industries; They're basically the final frontier of pornographic intergalactic conquest.
I mean, let's analyze the pros:
1) Lots of job security
I'll give you that, save for the pregnancy one. Job security? Come on, man... They only have 9 months of job security. Actually less than that if you really think about it. Presumably one would have to be showing to be of interest to the people who are into that kind of porn. That takes 3-4 months to get a noticable baby-bump going. So you really only have 5-6 months of pregnancy porn viability.
Not a solid long-term career move.
“Everybody has a secret world inside of them. All of the people of the world, I mean everybody. No matter how dull and boring they are on the outside, inside
them they've all got unimaginable, magnificent, wonderful, stupid, amazing worlds. Not just one world. Hundreds of them. Thousands maybe.” -Neil Gaiman