I wonder also. I almost died from it almost 30 years ago. My liver shut down, etc. I remember being so scared of having a child at that time and wonder if it was TMS. I am a barfy sort of gal anyway, with a stressy stomach, so it would fit. I remember the doctors in the hospital telling me they didn't know what caused HG, just that some women don't react well to the hormonal changes. This seems like a TMS red flag, though my understanding of the disorder is 30 years out of date now.
I am not looking for blame, just trying to understand my history better. It was very traumatic and very mysterious.