A further step in this direction has been effected by the introduction of reversibility into a non-reversible case by means of a catalytic agent.
This is the cycle employed by Carnot for the establishment of his fundamental principle of reversibility as the criterion of perfect efficiency in a heat engine.
As soon as this reversibility is introduced, general laws related to thermodynamics are applicable (see Chemical Action; Energetics).
Some of the benefits involve usability among breastfeeding women and smokers over thirty-five, less blood loss, fewer or less intense cramps, and the reversibility typically found with all birth control pills.
Such an introduction of reversibility is also possible by allowing sufficient time to permit the transformation to be produced by itself.