From the same article:
Data for the years 2007 to 2010 show the average weight of American women 20 years and older is 166.2 pounds—greater than the weight at which emergency contraceptive pills that use levonorgestrel begin to lose their effectiveness.
Data for the years 2007 to 2010 show the average weight of American women 20 years and older is 166.2 pounds—greater than the weight at which emergency contraceptive pills that use levonorgestrel begin to lose their effectiveness.