Prospective assessment of follicular growth and the oocyte cohort after ovarian stimulation for fertility preservation in 90 cancer patients versus 180 matched controls

A lower number of metaphase II oocytes eligible for vitrification after controlled stimulation in cancer patients has recently been reported, suggesting that cancer may impair the dynamics and quality of follicular growth. In this prospective, non-interventional study, the pattern of follicular growth and oocyte cohort after ovarian stimulation in cancer patients was analysed. Ninety cancer patients, recruited before starting chemotherapy, were compared with 180 time- and age-matched healthy controls undergoing intracytoplasmic sperm injection. Primary outcome was total number of metaphase II oocytes and metaphase II /total oocytes rate. Basal anti-Müllerian hormone levels (P < 0.05) and antral follicle count (P < 0.0001) were significantly lower in cancer patients. Recombinant FSH total dose was significantly higher in the cancer group (P < 0.0001). No differences were found in duration of stimulation, mean number of mature follicles on day of ovulation induction and total oocyte number after retrieval; the number of metaphase II oocytes retrieved (6.2 ± 4.7 versus 8.8 ± 4.2; P < 0.0001) and number of metaphase II oocytes–total oocytes ratio were significantly lower in cancer patients (56% versus 78%, P < 0.0001). Fewer metaphase II oocytes were eligible for vitrification and lower maturation rate in the cancer group.