Mechanically Engineered Umbilical Cord Mesenchymal Stem Cell-Derived Exosomes(Tang-Du Hospital)

The goal of this clinical trial is to evaluate if engineered mechanically umbilical cord-derived stem cell exosomes, or conventional umbilical cord -derived stem cell exosomes, can improve endometrial thickness in women with thin endometrium.
The main questions it aims to answer are:
Can exosomes delivered via subendometrial injection improve endometrial thickness or clinical pregnancy rates compared to PRP (platelet-rich plasma)? Are there significant differences in endometrial thickness between the two treatment groups? Researchers will compare the intervention groups, which one group receives mechanical exosomes and the other receives conventional esosomes via subendometrial injection, to the control group, which receives PRP via the same methods, to see if exosomes provide superior therapeutic effects.
Participants will:
Receive either mechanical exosomesor or conventional esosomes or PRP through subendometrial injection.
Be monitored for changes in endometrial parameters.