According to abortion rights advocate Reproaction, medication abortion pills, which are FDA-approved to terminate a pregnancy within the first ten weeks, are effective regardless of a person's weight.
Reproaction clarified that the efficacy of certain types of emergency contraception does decrease after weight thresholds are exceeded:
"Progestin-only pills containing levonorgestrel such as Plan B or My Way will be less effective for bodies over 155 lbs. Pills containing ulipristal acetate, such as ella, will be less effective for bodies over 195 lbs."
For those over the above weight limits, Reproaction noted that copper IUDs "have no weight restriction and are the most effective form of emergency contraception if inserted up to five days after unprotected intercourse."