Endometrium Immunomodulation to Prevent Recurrent Implantation Failure in Assisted Reproductive Technology.

After more than four decades of assisted reproductive technology (ART) practice worldwide, today more than 60% of women undergoing in vitro fertilization (IVF) treatments fail to become pregnant after the first embryo transfer and nearly 20% of patients are suffering from unexplained recurrent implantation failures (RIFs) and repeated pregnancy loss (RPL). The literature reported different causes of RIF-RPL, mainly multifactorial, endometrial and idiopathic. RIF remains a black box because of the complicated categorization and causes of this physio-pathological dysregulation of implantation and pregnancy process after ovarian stimulation. Many options were suggested as solutions to treat RIF-RPL with controversial results on their usefulness. In this article, we reviewed different possible therapeutic options to improve implantation rates and clinical outcomes. Based on our experience we believe that endometrium immunomodulation after intrauterine insemination of activated autologous peripheral blood mononuclear cells (PBMCs) or platelet-rich plasma (PRP) can be a promising therapeutic solution. On the other hand, peripheral lymphocyte balance typing, specific cytokines and interleukins profiling can be proposed as predictive biomarkers of implantation before embryo transfer.

[Impact of SARS-CoV-2 on fertility, gametes' quality and Assisted Reproduction Technology]. / Impact du SARS-CoV-2 sur la fertilité, les gamètes et l'Assistance médicale à la procréation.

The current pandemic context raises questions about COVID-19 consequences on Assisted Reproduction Technology (ART). Indeed, according to the first Biomedicine Agency recommendations, ART centers suspended their activities in March 2020 during the first wave of Covid-19. However, SARS-CoV-2 direct and indirect effects on gametes, fertility, pregnancy and neonatal health are still debated. The aim of this review is to assess the available data on this subject, to inform patients in care and adapt daily practice. Most recent studies are based on the effects of the infectious syndrome, on hormonal factors as well as on the expression of viral entry proteins (ACE2 and TMPRSS2) in cells involved in gametogenesis, to assess the impact of COVID-19. So far, no effect on female gametes was highlighted. More studies are needed to confirm this hypothesis. Mother to children transmission couldn't be proven, yet neonatal infection remains possible. However, men are more susceptible to be infected by SARS-CoV-2, to be symptomatic, and spermatogenesis is likely to be affected. Presence of the virus in semen is infrequently reported, but all of these parameters should be taken into account in ART.