Another case of the media misreporting science!
What the researchers actually said was not that MS is made up, but that the perception of it's severity is often exagerated. I can fully believe many women dash to doctor because they are concerned that even their mild retching will harm the baby. What the journalist put down as a headline was (effectively) "MS is made up". What journalist should have put down was "MS may not be as bad as you think it is" but that's too many long words for your average hack to spell properly.
Those of us who have truly severe MS are too ill to even drag ourselves to the GP, of course, which probably distorts the statistics.