Fertility preservation after gonadotoxic treatments for cancer and autoimmune diseases

The indications for fertility preservation (FP) have expanded. A few patients who underwent gonadotoxic treatment did not have the opportunity to receive FP, leading to concerns that these patients may develop premature ovarian insufficiency. However, the usefulness of FP in women with reduced ovarian reserve has also been questioned. Progestin-primed ovarian stimulation can improve the controlled ovarian stimulation (COS) protocol, but there is limited data on the efficacy of FP with progestin-primed ovarian stimulation. We conducted a prospective study of 43 women with cancer or autoimmune diseases before and after gonadotoxic treatment at the reproductive unit of Keio University Hospital, counselled between 1 January 2018 and 31 December 2021. After counselling, informed consent was obtained for FP from 43 patients, with those who underwent gonadotoxic treatment of the primary disease being prioritised. Gonadotropin-releasing hormone analogue or progestin was used to suppress luteinising hormone in COS before or after gonadotoxic treatment. The number of cryopreserved mature oocytes was the primary outcome. Forty-three patients and 67 assisted reproductive technology cycles were included in the analysis. The median age at entry was 32 [inter quartile range (IQR), 29-37] years. All patients in the post-gonadotoxic treatment group had their oocytes frozen. Gonadotoxic treatment resulted in fewer oocytes [median 3 (IQR 1-4); pre-gonadotoxic treatment group: five patients, 13 cycles] vs. median 9 (IQR 5-14; pre-gonadotoxic treatment group: 38 patients, 54 cycles; P