Multifactorial analysis of pregnancy rates in embryos transfer programs in Colombia

Objective. To analyze several characteristics of transferable embryo, as well as some of receptors on the pregnancy rates. Materials and methods. Hundred seventy four transfers were evaluated in two farms in Colombia. The analyzed variables in the receptors were serum progesterone levels, corpus luteum size and genetic group. The analyzed variables in embryos were stage of development, quality and transfer in fresh or frozen. Results. None of the variables individually predicts the rate of pregnancy, however, the probability of a better result exists when a frozen excellent embryo is used (OD=5.100), good fresh (OD = 4.180) and if the receptor is 3/4 Angus (OD = 2.945). Conclusions. The pregnancy rate continues being a regulated event in multifactorial way and none of the evaluated parameters individually is responsible for the reproductive success.