Many women who are deciding on fertility preservation (FP) are doing so at an advanced reproductive age, probably because this option has become available relatively recently, or due to the lack of awareness in young women about the depletion of the ovarian reserve and its effects on fertility. Recent studies show that age is the most powerful variable related to success after FP, which directly affects the number of oocytes vitrified, oocyte survival and cumulative live birth rate, with highest outcomes achieved by women aged ≤35y. Nonetheless, women in the ‘over 40’s’ can also succeed with their vitrified oocytes, although their probability of success is extremely low. An individualised treatment in older women, together with a comprehensive explanation of their situation to avoid creating false expectations, would be more advisable in order to set an age limit at 40 and deny the opportunity to these women. Likewise, women should be encouraged to decide on FP at young ages, when the chances are significantly higher.