Objective:To explore the different metabolites in the follicular fluids (FFs) of polycystic ovary syndrome (PCOS) patients and non-PCOS patients and their effects on the maturation of mouse oocytes and the developmental potential of in vitro fertilization (IVF) embryos. Methods:The clinical data were collected for the retrospective cohort study. Animal experiments were conducted in a randomized controlled trial. This study included PCOS ( n=71) and non-PCOS ( n=70) patients who underwent the first IVF or intracytoplasmic sperm injection (ICSI) cycle in Shanghai JIAI Genetics & IVF institute from June 2019 to June 2020. The patients' FFs were collected and the clinical data from these patients were analyzed. Raman spectroscopy analysis technology was used to detect differences in the metabolic spectra of FFs between the two groups. Mouse GV phase oocytes were placed in FFs from PCOS patients and non-PCOS patients for in vitro maturation (IVM) culture respectively, then the matured mouse oocytes were collected for IVF. The effects of differential metabolites in FFs on mouse oocyte maturation and embryonic development were further explored. The Raman spectrum was also applied to identify the differences of the IVM spent culture media. Results:The MⅡ rate [82.19% (886/1 078)] and day 3 available embryo rate [51.30% (553/1 078)] from PCOS group were significantly lower than those of the non-PCOS group [85.85% (625/728), P=0.038; 53.30% (388/728), P=0.042]. However, there were no significant differences between the two groups in the cumulative clinical pregnancy rate and the cumulative live birth rate (all P>0.05). Raman was capable of distinguishing PCOS from non-PCOS FFs. The characteristic Raman displacement difference between the two groups is mainly concentrated in the 600-1 000 cm -1, as well as 1 168 cm -1, 1 344 cm -1, 1 440 cm -1, 1 504 cm -1, 1 632 cm -1 and 1 664 cm -1. The Raman characteristic shift database showed that the different metabolites of the two sets of FFs samples were mainly concentrated in protein, lipids, free nucleic acis, glucose, cholesterol, carotenoids, and amino acids. Mouse oocyte IVM results showed that the PCOS-FF group had a lower MⅡ rate [49.04% (77/157)] than that of non-PCOS group [65.07% (95/146), P=0.005). IVF results showed the PCOS-FF group had a significantly lower cleavage rate [46.75% (36/77)] than that of non-PCOS group [63.16% (60/95), P=0.031], but there was no significant difference in the blastocyst rate between the two groups ( P>0.05). Conclusion:Differential metabolites detected by Raman spectrum in the PCOS FFs may cause defected maturation of the oocytes, leading to infertility, and Raman spectroscopy is an effective approach towards PCOS diagnosis and the identification of metabolomics differences.

Objective:To explore the different metabolites in the follicular fluids (FFs) of polycystic ovary syndrome (PCOS) patients and non-PCOS patients and their effects on the maturation of mouse oocytes and the developmental potential of in vitro fertilization (IVF) embryos. Methods:The clinical data were collected for the retrospective cohort study. Animal experiments were conducted in a randomized controlled trial. This study included PCOS ( n=71) and non-PCOS ( n=70) patients who underwent the first IVF or intracytoplasmic sperm injection (ICSI) cycle in Shanghai JIAI Genetics & IVF institute from June 2019 to June 2020. The patients' FFs were collected and the clinical data from these patients were analyzed. Raman spectroscopy analysis technology was used to detect differences in the metabolic spectra of FFs between the two groups. Mouse GV phase oocytes were placed in FFs from PCOS patients and non-PCOS patients for in vitro maturation (IVM) culture respectively, then the matured mouse oocytes were collected for IVF. The effects of differential metabolites in FFs on mouse oocyte maturation and embryonic development were further explored. The Raman spectrum was also applied to identify the differences of the IVM spent culture media. Results:The MⅡ rate [82.19% (886/1 078)] and day 3 available embryo rate [51.30% (553/1 078)] from PCOS group were significantly lower than those of the non-PCOS group [85.85% (625/728), P=0.038; 53.30% (388/728), P=0.042]. However, there were no significant differences between the two groups in the cumulative clinical pregnancy rate and the cumulative live birth rate (all P>0.05). Raman was capable of distinguishing PCOS from non-PCOS FFs. The characteristic Raman displacement difference between the two groups is mainly concentrated in the 600-1 000 cm -1, as well as 1 168 cm -1, 1 344 cm -1, 1 440 cm -1, 1 504 cm -1, 1 632 cm -1 and 1 664 cm -1. The Raman characteristic shift database showed that the different metabolites of the two sets of FFs samples were mainly concentrated in protein, lipids, free nucleic acis, glucose, cholesterol, carotenoids, and amino acids. Mouse oocyte IVM results showed that the PCOS-FF group had a lower MⅡ rate [49.04% (77/157)] than that of non-PCOS group [65.07% (95/146), P=0.005). IVF results showed the PCOS-FF group had a significantly lower cleavage rate [46.75% (36/77)] than that of non-PCOS group [63.16% (60/95), P=0.031], but there was no significant difference in the blastocyst rate between the two groups ( P>0.05). Conclusion:Differential metabolites detected by Raman spectrum in the PCOS FFs may cause defected maturation of the oocytes, leading to infertility, and Raman spectroscopy is an effective approach towards PCOS diagnosis and the identification of metabolomics differences.