Informing the gravid void: A population-based study of live birth rates after oncologic immunotherapy in reproductive age women.

Abstract

e14654 Background: Immunotherapy is a new standard oncologic treatment modality in nearly every organ system, however fertility sequalae are yet to be defined. Oncologic immunotherapy has been proposed by various theoretical mechanisms to decrease female fertility in animal models. Only case reports of pregnancies after immunotherapy exist in the literature. This study sought to describe real world population based-data on the live-birth rate after oncologic immunotherapy. Methods: This was a population-based retrospective cohort study of female patients between the age of 15 and 49 diagnosed with melanoma, non-small cell lung cancer, urothelial bladder and kidney cancer, or head and neck cancer, between 2012 and 2021 in Ontario, Canada. Primary exposure was oncologic immunotherapy with PD-L1 inhibitors, PD-1 inhibitors and CTLA inhibitors, and patients were followed from date of diagnosis for a minimum of 1 year up to age 50, hysterectomy, pelvic radiation, death or end of the follow up period (2022). Descriptive statistics were used to calculate the rate of live births per reproductive age woman years and rate of reproductive events per reproductive age woman years. Results: 5, 796 women met inclusion criteria of whom 333 (5.7%) received oncologic immunotherapy. The mean age of those who did and did not receive oncologic immunotherapy was not different (40.4 years (SD 6.7) vs 39.9 years (SD 7.7), p = 0.07). Approximately half of the women in both groups were diagnosed with melanoma (55.0% and 54.2%). Advanced stage at diagnosis was significantly more common in the group treated with oncologic immunotherapy (p < 0.0001). 297 (89.2%) women received PD-1 inhibitors, 118 (35.4%) CTLA inhibitors and 22 (6.6%) PD-L1 inhibitors. 13 (3.9%) patients who received oncologic immunotherapy had at least one live delivery, while 451 (8.3%) patients who did not receive oncologic immunotherapy had at least one live delivery. There was no statistical difference in the number of still births or abortions between the groups (p = 0.33 and p = 0.89). The rate of live-births after cancer diagnosis per 1000 reproductive age woman years was 18.5 (95%CI 11.2-30.7) in patients who received oncologic immunotherapy and 27.9 (95%CI 25.7-30.2) in patients who did not receive oncologic immunotherapy. The median time from first oncologic immunotherapy to first live birth was 2.02 years (range 1.78-2.26 years). The rate of reproductive events after cancer diagnosis per 1000 reproductive age woman years was 28.4 (95%CI 18.9-42.7) and 34.7 (95%CI 32.3-37.3) respectively. Conclusions: Women are having live births after oncologic immunotherapy, and preliminary real world population-based data suggests their rate of live births and reproductive events may be similar to that of women diagnosed with cancer who receive oncologic treatment not including oncologic immunotherapy.