P-114 Abdominal obesity in Polycystic ovary syndrome patients can increase endometrial stromal cells decidualization

Abstract

Abstract Study question Whether abdominal obesity can change the decidualization induction potential in PCOS patients? Summary answer We hypothesized that considering the inflammatory origin of abdominal obesity, it may affect decidualization potential of endometrial stromal cells (ESCs). What is known already Polycystic ovary syndrome (PCOS) as a chronic inflammatory disease is the most common hormonal disorder in women of reproductive age, which is often associated with subfertility or infertility due to ovulation disorders and subsequently low pregnancy rate, live birth rate and a high miscarriage rate. Inflammatory Abdominal obesity (AO) is the most common phenotype in PCOS patients, which has a high association with PCOS pathogenesis. Embryo-endometrium cross-talk has a key role in successful embryo implantation, which contains inflammatory phase (decidualization induction). Followed by inflammatory phase for pregnancy support. Study design, size, duration Our study population were consisting of 53 infertile women including PCOS diagnosed according to Rotterdam criteria (n = 25) and normal oogenesis women (male factor infertility) (n = 28) with in vitro fertilization (IVF) / intracytoplasmic sperm injection (ICSI) and frozen embryo transfer (FET) indication. All patients were aged 25-35 referred to Royan Institute between 1st May until 1st December in 2021 for infertility treatments. Participants/materials, setting, methods The embryos were subdivided into four groups: PCOS with AO, PCOS without AO, nonPCOS with AO, and nonPCOS without AO patients. The embryos from each group were single cultured up to the blastocyst stage. Their embryo condition media (ECM) were pooled and added to the culture media of healthy ESCs monolayer to investigate their effects on decidualization potential via gene and protein expression analysis and ESCs migration assay. Main results and the role of chance Results showed that ECM generally can improved decidualization capacity in ESCs. Morphological analysis, migration assay, protein and gene expressional analysis showed PCOS with AO had the highest decidualization potential and revealed by higher expression of decidualization markers (P ≤ 0.05). NonPCOS individuals without AO had the lowest level of both gene and protein decidualization markers (P ≤ 0.05). Limitations, reasons for caution Due to small sample population and the ECM volume limitation, the present study remained focused on the some main decidualization markers rather than extended study. Wider implications of the findings Inflammation may increase endometrial receptivity, allowing more suboptimal embryos to implant; this could explain the high rate of abortion in these cases. Controlling the inflammation in PCOS patients with AO may correct the decidualization profile of these patients. Trial registration number Not applicable