For one weighing over 180 lbs, is plan B effective?

Good morning, Madam, Sorry for the delay in responding. It seems that your account was never activated when you asked your question, which explains this delay. You have a very good question! According to the data available at the moment, it seems that the morning-after pill (or emergency contraception) is less effective in women weighing more than 75 or 80 kg (about 170 lbs). Studies on the subject show a reduction in effectiveness by a factor of 2 to 4 (i.e. 2 to 4 times less effective). In obese women, some studies even show an almost complete loss of effectiveness. It is recommended that these women use emergency contraception by inserting an IUD, which is more difficult to do in practice because a doctor must be consulted relatively quickly after unprotected sex. I hope this answers your question. Have a nice day, Alexandre