Investigation of an efficient method of oocyte retrieval by dual stimulation for patients with cancer

Purpose To examine the optimal timing of second ovarian stimulation using the dual stimulation method for good ovarian responders with cancer undergoing oocyte retrieval for fertility preservation. Methods A retrospective analysis was conducted using data from 69 patients with cancer who underwent oocyte retrieval for fertility preservation at four Japanese institutions during 2010–2021. Twenty‐two patients underwent two oocyte retrievals for fertility preservation. We studied the relationship between the initial number of oocytes retrieved via dual stimulation and risk of ovarian enlargement as well as the appropriate waiting interval between the end of the first ovarian stimulation and beginning of the second ovarian stimulation. Results The risk of ovarian enlargement was high when the initial number of oocytes retrieved via dual stimulation was ≥5. An 8‐day waiting interval may be more effective for performing a second ovarian stimulation oocyte retrieval in these cases, although the difference was not significant. Conclusions This study provides one policy for effectively managing ovarian enlargement and timing of second ovarian stimulation during oocyte retrieval via the dual stimulation method for patients with cancer undergoing fertility preservation. If more facilities implement this procedure, more oocytes may be obtained in a short period for fertility preservation purposes. An 8‐day waiting interval after the first ovarian stimulation and at least five oocyte retrieval led to good results of dual stimulation for cancer patients with good ovarian response.