Objective: To demonstrate the changes of ovarian aging markers across the Stages of Reproductive Aging Workshop (STRAW) stages and modify it with subclassification of mid reproductive age stage (MR). Design: Healthy females were classified according to the STRAW system. Serum basal FSH, LH, E2, and anti-Mullerian hormone (AMH) were detected, FSH/LH ratio calculated, and antral follicle counts (AFCs) determined in follicular phase. Results: Progression through the whole STRAW stages under MR stage subdivided is associated with elevations in FSH, LH, FSH/LH ratio and decreases in E2, AMH and AFCs (p < 0.001). Both serum AMH and AFCs decreased early (after 25 years) and significantly (p < 0.01) with chronological age in MR stage. 0.982 ng/ml AMH and 3 antral follicles (low level of MR 25-30 years) were set as cutoffs to distinguish MR stage into early mid reproductive age (EMR) and late mid reproductive age (LMR) stages. The women in EMR stage compared with LMR could retrieve more oocytes in IVF treatment (p < 0.05) and has a higher pregnancy chance (57.9%) though not significant. Conclusion(s): The early and marked fall in serum AMH levels and AFCs suggest fine markers to further categorize and define the MR stage, demonstrating disparate reproductive aging period with reduced ovarian reserve in young age across the STRAW stages.