Decreased ovarian reserve: any new hope?

While diminished ovarian reserve (DOR) predicts decreased ovarian response to stimulation, it does not necessarily foretell about the fecundity cycle. According to Bologna's criteria laid down by the European Society of Human Reproduction and Embryology, old age, abnormal ovarian reserve tests such as antral follicle count (AFC) and anti-mullerian hormone (AMH) as well as prior suboptimal response to stimulation are the main factors representing DOR. Unfavorable response to maximal stimulation on two previous occasions may also represent DOR. Among the ovarian reserve tests, AMH and AFC are the most predictive values for DOR. Factors which may give rise to DOR include environmental factors, autoimmune or metabolic disorders, infections, genetic abnormalities, and iatrogenic causes (such as smoking, chemotherapy, radiation and gynecologic surgeries). Besides, studies have proposed endometriosis as a key contributor to DOR and hence emphasized on its proper management to prevent additional damages leading to compromised fertility. In summary, DOR is found to be a clinical challenge in the practice of fertility care with controversial countermeasures to prevent or treat the condition. Nevertheless, some promising measure such as: oocyte, embryo and tissue cryopreservation, ovarian transplantation, dietary supplementation and the transfer of mitochondria have offered hopes towards ameliorating the burden of DOR. This review attempts to discuss DOR from different perspectives and summarize some existing hopes in clinical practice.