Objective:

To investigate the impact of thyroid autoimmunity (TAI) on fertilization outcomes in euthyroid infertile women undergoing in vitro fertilization–embryo transfer (IVF-ET), and to identify key follicular fluid exosomal miRNAs associated with TAI.

Approach:

• Study Design: Retrospective analysis of 4,332 infertile women aged 20–40 years undergoing IVF-ET.
• TAI Definition: TAI defined as TPOAb >34 IU/mL and/or TgAb >115 IU/mL.
• Statistical Analysis: Fertilization rates compared using Wilcoxon rank-sum test; generalized linear models assessed TAI's association with outcomes.
• miRNA Sequencing: Follicular fluid samples from 10 TAI-positive and 10 TAI-negative women analyzed for exosomal miRNA sequencing.
• miRNA Identification: Differential expression analysis and machine learning techniques (LASSO, SVM) used to identify key miRNAs.

Key Findings:

• Among the 4,332 infertile women, 565 were TAI-positive and 3,767 were TAI-negative. TAI-positive women had significantly lower fertilization rates compared to TAI-negative women (p 0.7).

Interpretation:

The study found that TAI is associated with impaired fertilization outcomes in euthyroid infertile women undergoing IVF-ET, linked to altered exosomal miRNA profiles in follicular fluid.

Limitations:

• Retrospective design may introduce selection bias.
• Study conducted at a single center, limiting generalizability.

Conclusion:

The study indicates that TAI is associated with impaired fertilization outcomes and altered miRNA expression in follicular fluid.