A DIFFICULT TRANSFER FOLLOWED BY A CLINICAL PREGNANCY. NEW CONCLUSIONS RELATED TO A PREVIOUSLY REPORTED CLINICAL CASE

Abstract
Traumatic embryo transfers impact negatively on pregnancy rates. We have previously reported a clinical pregnancy and the birth of a healthy baby by transferring a blastocyst developed in a standard medium (P-1) from a 72 hours embryo which had been retained on the catheter during a traumatic transfer. Now we are reporting new results and conclusions obtained after the clinical case reported in that opportunity. A retrospective study of the development of embryos in a standard medium (P-1) from a heterogeneous group of patients was carried out at our IVF center. We found that the transfer of blastocysts cultured in a single medium (in this case, P-1) does not improve the overall implantation and pregnancy rates. These rates are higher with the transfer of blastocysts produced by the use of sequential media. In spite of this, our results show that in certain cases, those laboratories0 which do not always have sequential media because they do not transfer blastocysts as a routine, can obtain blastocysts using single media and achieve acceptable implantation and pregnancy rates.

Key words
IVF, blastocyst, single media

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