The lines of research that these scientific papers follow are based on improving the success rates, most specifically in older patients with low ovarian response, or with implantation failure or repeat miscarriages. Likewise, and as characterized by the excellence of Instituto Bernabeu, these projects are focused on the latest advances that we have carried out in embryo genetics.

"Comprehensive chromosome screening (CCS) improves IVF outcome in recipients suffering recurrent implantation failure (RIF) and pregnancy loss (RPL)"

This advance reveals that patients with repeat miscarriages or implantation failure have a higher percentage of chromosomal abnormalities in their embryos.

The use of Comprehensive Chromosome Screening (CCS) techniques allow us to select and transfer embryos without these abnormalities, improving the success rates of assisted reproduction treatments for patients who until now haven’t had pregnancies leading to a healthy baby.

"Comprehensive chromosome screening (CCS) increases the implantation rate in advanced maternal age."

After analysing the Array-CGH result of 195 blastocysts from 62 cycles of IVF, we got a revealing conclusion: the selection of euploid embryos equals the implantation rate in women of advanced age and in young women.

This study therefore proves that the comprehensive chromosome screening is a promising option for improving the results of IVF cycles mainly in female patients of advanced age.

"Incidence of aneuploidy in oocytes from egg donation cycles"

In this research, accepted as a speech in the British Fertility Society Conference, we have analysed the female contribution to embryo chromosome abnormalities. For this reason, we have studied the gametes of a group of young fertile patients, as are egg donors, comparing them with eggs of patients of more advanced age.

CCS or Comprehensive Chromosome Screening reduces spontaneous miscarriages and increases the chances of successful pregnancy in this group of patients by allowing the transfer of only chromosomally normal embryos.

In addition, the following researches were also presented at the annual British Fertility Society Conference:

· Embryo vitrification on day 4 increases the survival rate in oocyte recipients. Poster.

· Embryos with delayed development at day 5 must be frozen. Implantation rates of grade 1 "blastocysts" better in frozen embryo transfers. Oral presentation.

· Does donor body mass index affect the final outcome in egg donation? Poster.