Death in the production of ruminant embryo is still a major obstacle, especially inprograms of IATF and recipients of embryo. In the initial stage of pregnancy, called the criticalperiod, which occurs in more than 70% of losses, this time a series of reactions occur so that there isa physiological adjustment of pregnant to not pregnant, the maternal recognition of pregnancy inwhich the concept must signal its presence by inteferon release of tau to inhibit the programmeddischarge of prostaglandin 2 alpha. The progesterone produced by the corpus luteum is one of thefactors that go down to oxytocin binds to its receptors stimulated by the action of estrogen receptorsin stimulating the production of PGF2α to cause luteolysis. The IFN-τ produced by the concept bindsto endothelial cells in the endometrium prevents the production of PGF2α and luteolysis. To improvethe rates of embryo death is necessary to make development of anti-luteolíticas, to reduce the levelsof estrogen to minimize the stimulus in OTCR, controlling the release of PGF2α, slowing or blockingthe luteolysis aumentandar or the concentration of circulating progesterone this same period.Increasing the concentration of P4, use of hCG, GnRH and ECG, are strategies to stimulate the mechanism of anti-luteolysis, and strategies involving use of specific diets among others.