Case report: Immature oocyte retrieval in the luteal phase to preserve fertility in cancer patients

As cancer treatment outcomes improve, the number of women with cancer seeking fertility preservation increases. Currently, embryo/oocyte cryopreservation appears to provide the best fertility preservation option. However, patients may not have sufficient time to undergo ovarian stimulation prior to chemotherapy and/or the hormones used in ovarian stimulation are contraindicated for certain tumours. In-vitro maturation has been suggested as an effective treatment for these patients. This report presents three women aged 21, 30 and 40 years, without male partners, seeking fertility preservation prior to chemotherapy. They were first seen during the luteal phase of their menstrual cycle and were to undergo gonadotoxic treatment imminently. They underwent immature oocyte retrieval in the luteal phase and seven, five and seven immature oocytes were recovered, respectively. After in-vitro maturation, five, three and five metaphase II (MII) oocytes were vitrified. Two patients later underwent one and two more retrievals, respectively, in the follicular phase of the next cycle(s) and additional oocytes were cryopreserved. These results suggest that immature oocytes recovered in the luteal phase can successfully be matured in vitro; therefore, if there is not sufficient time for conventional follicular-phase oocyte retrieval in a stimulated/ unstimulated cycle prior to chemotherapy, a retrieval in the luteal phase could be considered.