Fig. 1

The probabilities of usage after storage years among the different age groups at oocyte freezing. The probability of each group was presented as a cumulative incidence curve. The probabilities of thawing the oocytes were 10.6%, 26.6%, and 12.7% for women who cryopreserved their oocytes at age ≤ 35 years, 36–39 years, and ≥ 40 years, respectively. No significant difference exists (P = 0.3040)