Suing to have patients pay for the services he had rendered? What an A-hole!
The NYT claims Sen. Marshall sued 700 former OB patients. SSuming the NYT is correct and gave complete info, let's do a little Math. Per DDG, the average doctor cost in the US for a baby delivery is $18,865. Rounding that down to $15K for Mathematic convenience, those 700 non-paying patients were $10,500,000 of Sen. Marshall's services - from which he would have paid his staff, office/clinic rent, any applicable hospital access fees, and gawdawfull malpractice insurance premiums.
As for the "pre-existing condition"

, if you for some reason start a new insurance plan mid pregnancy, that does apply. It would apply to any medical condition known before starting the new insurance plan. Doctors have zero to do with insurance companies' plan terms. Are DUmmies DUmb enough to think Sen. Marshall crafted pre-existing condition limitation terms?