Blame every person who thought it was a good idea to sue the hospital because of a complication caused by their poor lifestyle choices.
You probably hit two or three criteria on a risk assessment matrix so you get bumped.
My wife went through through a similar issue. Not due to BMI etc but as she was deemed high-risk first time (due to an undiagnosed blood disorder that is now completely under control and was under control the duration of the pregnancy) we had to go through the Joy of paying a private OBGYN to deliver in a public hospital.
Welcome to the stage in life where you've worked hard enough that you get to pay for everything and get nothing in return.