The impact of thyroid function, autoimmunity, and subsets of Th cells in follicular fluid on ovarian reserve and embryo quality in assisted reproductive technology (ART)

Abstract

Both thyroid function and autoimmunity have the potential to influence fertility and pregnancy outcomes; however, the underlying mechanisms remain inadequately understood. The purpose of this study is to explore the effects of thyroid function, autoimmunity, and subsets of Th cells in follicular fluid on ovarian reserve and embryo quality. In this prospective cohort study, 104 patients were enrolled and divided into an observation group (TSH >2.5 μIU/mL or diagnosed hypothyroidism) and a control group, each with 52 patients. Follicular fluid samples from infertility treatments were analyzed for subsets of Th cells using flow cytometry, and thyroid function and autoimmunity in the fluid were measured. The ovarian reserve and embryo quality were evaluated. In the correlation analysis, it was observed that FT4, TSH, and TPOAb were significantly correlated in serum and follicular fluid (P < 0.05). However, no correlation was identified between subsets of Th cells and TPOAb in either serum or follicular fluid. In the multiple linear regression analysis, Th17/CD4⁺T lymphocytes demonstrated a statistically significant negative effect on the number of antral follicles (P = 0.021). Conversely, no significant effects were observed for thyroid function, TPOAb, or subsets of Th cells on the number of oocytes retrieved, fertilization rate, or the number of good-quality embryos.Our study indicates that Th17 cells present in follicular fluid may adversely affect ovarian reserve. Conversely, no significant effects were observed regarding thyroid function, TPOAb, or subsets of Th cells in follicular fluid on the quantity of oocytes retrieved, fertilization rates, or embryo quality.