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.

Objective: This study investigated oxidative stress and its impact on sperm quality in men with infertility, focusing on lipid peroxidation and the activity of antioxidant enzymes—catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx)—in seminal fluid. Methods: This study was conducted from January 2021 to January 2023 and involved 163 male patients who had been experiencing infertility for over a year. The participants were categorized according to semen quality. Semen samples were analyzed for sperm concentration, motility, and morphology following the World Health Organization guidelines. Oxidative stress was evaluated by measuring levels of malondialdehyde (MDA), an indicator of lipid peroxidation, as well as the activity of CAT, SOD, and GPx. Ethical approval and informed consent were obtained from all participants.Results: Semen quality and oxidative stress were evaluated in cases of male infertility, with patients categorized into five groups: normozoospermia, oligozoospermia, asthenozoospermia, teratozoospermia, and oligo-astheno-teratozoospermia. The pathological groups exhibited significant reductions in sperm count, motility, and morphology. Additionally, lipid peroxidation, as shown by increased MDA levels, was significantly elevated in all pathological groups. The activities of CAT, SOD, and GPx were significantly diminished in these groups, with the most substantial declines noted in the oligo-astheno-teratozoospermia group. Conclusion: Oxidative stress, indicated by elevated MDA levels, was correlated with poor sperm quality. The decreased activity of antioxidant enzymes in pathological semen implies that a weakened antioxidant defense contributes to sperm dysfunction. These findings suggest that antioxidant interventions could improve sperm quality in men experiencing infertility, though additional research is required.

The different Assisted Reproductive Technology techniques are offering hope to millions of couples struggling with infertility. However, the success of IVF/ICSI is related at least partially to the optimization of embryo culture conditions, which are influenced by myriad of physiological and environmental factors. This review reports the latest advancements in embryo culture techniques, with a particular focus on the roles of oxygen tension, pH regulation, temperature stability, air quality in enhancing embryo viability, competency and implantation rates. In addition, we explored the critical importance of quality assurance (QA) factors and key performance indicators (KPIs) to keep laboratory efficiency. We highlighted also some emerging technologies, such as dynamic culture systems, metabolomics, proteomics biomarkers potential, and artificial intelligence (AI) in embryo selection and monitoring, which hold promise for further improving embryo culture techniques. By providing a comprehensive overview of the current state of embryo culture optimization, this review aims to guide future research and clinical practices in the field of assisted reproductive technology (ART).