September 2026 newsletter

Hematological diseases have several distinctive characteristics. They can affect very young children as well as adults. Their treatments involve varying degrees of gonadotoxicity, ranging from chemotherapy regimens with low gonadotoxic potential (e.g., ABVD: doxorubicin, bleomycin, vinblastine, and dacarbazine) to conditioning regimens administered before hematopoietic stem cell transplantation (HSCT), which are highly gonadotoxic. These diseases can also cause thrombocytopenia, leukopenia, anemia, and a very rapid deterioration in the patient’s overall health. Consequently, certain treatments may need to be initiated urgently due to a very poor short-term prognosis. Although fertility preservation (FP) is an integral part of patient care, its implementation can be particularly challenging in this clinical context. Despite the recommendation to perform FP before treatment (Su HI et al., 2025), this is not always feasible in clinical practice.

Nevertheless, it is now clear that ovarian tissue cryopreservation is possible after the initiation of chemotherapy (Dolmans MM et al., 2021). In the context of hematological diseases, it has also been shown that ovarian tissue cryopreservation can be performed either long after chemotherapy and before a planned highly gonadotoxic treatment for a relapse, or during chemotherapy, without altering the cumulative rates of ovarian function recovery and pregnancy in these two groups of patients (Poirot C et al., 2019).

In contrast, oocyte cryopreservation is recommended before the initiation of chemotherapy due to the potential risk of treatment induced genetic damage. However, oocyte cryopreservation remains the method of choice for preserving fertility after treatment, which should also be considered as an important therapeutic goal (Rives N et al., 2021). This approach may be relevant for patients who have been cured or are in remission but did not undergo FP before treatment, due to disease related factors (e.g., severe thrombocytopenia or neutropenia, the need for urgent treatment…), patient-related factors (e.g., poor clinical conditions or cultural barriers) or a lack of awareness of available FP techniques, particularly in the early 2000s. It may also be considered as a complementary strategy in patients who underwent FP prior treatment but whose stored material is deemed insufficient to provide a realistic chance of achieving pregnancy.

Despite this important issue in patient care, few teams have reported on their experience with post-treatment fertility preservation (Lehmann V et al., 2020; Miquel L et al., 2023; Shapira M et al., 2025). The aim of our study was to evaluate, in a retrospective study, the acceptability and feasibility of fertility preservation based on prior treatments received for a hematological disease (Chalas C et al., 2026).

This study included 58 consecutive patients, referred by their hematologist, to the FP consultation, irrespective of any desire for childbearing. None of the patients had been seen for FP consultation at the time of their disease. Patients were categorized into three groups based on their prior treatment. Patients in the first group (G1, n=19) had undergone HSCT; those in the second group (G2, n=32) had undergone chemotherapy containing alkylating agents; and those in the third group (G3, n=7) had undergone chemotherapy without alkylating agents. Post-treatment ovarian function assessment was available for 48 patients.

As expected, women who had undergone HSCT had significantly impaired ovarian reserve compared with groups G2 and G3 (p ≤ 0.001). Patients in G2 and G3 did not differ significantly in terms of ovarian function, although G2 had a higher percentage of patients with diminished ovarian reserve. Ten women became pregnant naturally, mainly in G2 (9 out of 10) and 1 in G3.

Thirty women had ovarian reserve levels deemed suitable for controlled ovulation stimulation, and 11 women underwent the procedure: 2 in G1, 6 in G2, and 3 in G3. The other 19 patients declined the offer. The median number of vitrified oocytes was 6, ranging from [0–20]. The number of oocytes was lowest in G1 (n=2). Furthermore, the number of oocytes retrieved was similar in G2 and G3, even though the patients in G2 had been treated with alkylating agents.

Conclusions

This study, which categorized patients according to the treatment they had previously received, helps identify those who are most likely to benefit from post-treatment fertility preservation. Women who have undergone with HSCT are poor candidates for post-treatment FP. In contrast, women who have been treated with alkylating agents at doses that are not considered fully gonadotoxic, have a substantial likelihood of achieving a natural pregnancy and may therefore be good candidates for post-treatment FP, even when their ovarian reserve appears to be impaired. It is also important to mention the low acceptability rate of this technique. Accordingly, patients considering post-treatment fertility preservation should receive individualized counseling based on their previous treatment and its potential impact on ovarian function.

References

Su HI, Lacchetti C, Letourneau J, et al. Fertility Preservation in People With Cancer: ASCO Guideline Update. J Clin Oncol. 2025 Apr 20;43(12):1488-1515.

Dolmans MM, von Wolff M, Poirot C, et al. Transplantation of cryopreserved ovarian tissue in a series of 285 women: a review of five leading European centers. Fertil Steril. 2021 May;115(5):1102-1115.

Poirot C, Fortin A, Dhédin N, et al. Post-transplant outcome of ovarian tissue cryopreserved after chemotherapy in hematologic malignancies. Haematologica. 2019 Aug;104(8):e360-e363.

Rives N, Courbière B, Almont T, et al. What should be done in terms of fertility preservation for patients with cancer? The French 2021 guidelines. Eur J Cancer. 2022 Sep;173:146-166.

Lehmann V, Kutteh WH, Sparrow CK, Bjornard KL, Klosky JL. Fertility-related services in pediatric oncology across the cancer continuum: a clinic overview. Support Care Cancer Off J Multinatl Assoc Support Care Cancer. 2020;28(8):3955-3964.

Miquel L, Liotta J, Hours A, et al. Feasibility and efficiency of delayed ovarian stimulation and metaphase II oocyte banking for fertility preservation and childbearing desire after fertility-impairing treatment. Sci Rep. 2023;13(1):15661.

Shapira M, Meirow D, Raved D, et al. Controlled ovarian stimulation for oocyte preservation in childhood cancer survivors who have undergone chemotherapy. Hum Reprod Open. 2025;2025(2):hoaf023.

Chalas C, Chevillon F, De Fontbrune FS, et al. Acceptability and feasibility of post-treatment fertility preservation in women previously treated for hematological diseases. Haematologica. 2026 Apr 2.

Authors: Céline Chalas^1*, Catherine Poirot²*

• Department of Reproductive Biology, Cochin Hospital, Paris, France
• Department of Hematology, AYA Unit, Fertility Preservation,

Saint-Louis Hospital, Paris, France

*Please note: The newsletter reflects the opinion of the author and not of the ISFP.