As shown in Fig. 2a,b, there was no difference in the expression of CD25 on CD4+ or CD8+ T cells between the PCOS and NOW (P > 0.05); however, the expressions of CD69 in the PCOS group with infertility were significantly decreased both on CD4+ T cells (P < 0.05) and CD8+ T cells (P < 0.01) compared to the infertile patients with normal ovulation. Here, CD69 is linked to polycystic ovary syndrome.