Stress
There's a good reason they're called "post-production houses." You'll be living in your editing room until the job is done. You'll live on caffeine, vending machine food, and take-out.
Women have been professional editors for a long time and are represented well in the industry. Working in two homes is a strain that continues to fall on women, though, so this career could be extremely stressful if you've got a family. Better put that babysitter on speed dial.
And don't forget, you aren't just toting hay bales, you have to be creative on a deadline. That means coming up with alternatives on the fly. You might work on something for a week and have a network executive demand a different ending…and you'll have to do it and smile.