Is maximalisation of the ovum pick-up procedure beneficial for the outcome of assisted reproductive technology cycles?

To examine if aspiration of more oocytes than the sonographic assessment of antral follicle count (AFC) is beneficial for the current (pregnancy/livebirth rates) and future products of an ART cycle. Data of the first oocyte aspiration for ICSI performed between 2018-2022 in attempt to conceive (ICSI, n = 399) or for planned oocyte vitrification (fertility preservation FP, n = 283) was retrieved. The AFC was determined by professional sonographers using a 9 MHz transvaginal ultrasound probe. The most adjacent measurement to the stimulation initiation was used. Each group was divided into two subgroups according to their ‘oocyte/AFC index’ (OAFCI): <1 and 1. The stimulation parameters, number of aspirated oocytes, their maturity rate, number of cryopreserved oocytes/embryos, clinical pregnancy (CPR) and livebirth rates (LBR) were compared between the subgroups. Oocyte maturity was unaffected by the OAFCI in the ICSI group, but was lower in FP group at OAFC≥1 (0.79 vs. 0.84 p = 0.005). OAFCI≥1 was associated with a higher number of cryopreserved embryos (ICSI, 3.9 vs. 2.3, p < 0.001) and a higher number of vitrified oocytes (FP, 13.4 vs. 6.4 p < 0.001). The OAFCI had no impact on CPR (20% vs. 25%, p = 0.27) and LBR (19.9% vs. 24.8%, p = 0.33). On multivariate analysis controlling for age, gonadotrophin dosage and duration of stimulation, OAFC≥1 was associated with a higher number of cryopreserved embryos (aOR 1.2, 95% CI 1.1-1.3, p < 0.001) in the ICSI group and higher vitrified oocytes (aOR 1.2, 95% CI 1.1-1.2, p < 0.001) and lower maturity index (aOR 0.1, 95% CI 0.03-0.51, p < 0.001) in the FP group. Aspirating more oocytes than the AFC does not influence the outcome of the fresh cycle but harbours the possibility to cryopreserve more oocytes and embryos. This might translate into higher cumulative pregnancy rates later on.