The FDA just approved a pill that will rival Plan B and its competitors, but with an edge. Unlike the current “morning after” pills, that begin losing efficacy within 24 hours and are ineffective after 72 hours, the new pill works just as well 5 days later.
The prescription-only drug, which has been available in Europe since May 2009, is a progesterone agonist/antagonist that is thought to work by inhibiting or delaying ovulation, according to a statement from the FDA.
But ella has its detractors, as well. Experts believe the drug works by delaying the ability of the ovaries to produce an egg. However, opponents note that progesterone is also required to help the womb prepare for an already fertilized egg -- raising the possibility that the drug works similarly to RU-486, which prevents a fertilized egg from implantation in the womb.