Association between oocyte retrieval technique and number of oocytes retrieved

To assess if there is an optimal oocyte retrieval (OR) technique to retrieve a maximum number of oocytes and mature oocytes (MII).

Retrospective cohort study in which nine physicians completed a survey on OR techniques. Number of oocytes/follicle cohort, MIIs/follicle cohort, and MIIs/oocytes retrieved (%MII) were assessed for each technique for patients undergoing OR from 3/2013 to 7/2019. Data were stratified by number of follicles on ultrasound on day of trigger (< 6, 6-10, > 10).

Patient demographics were equivalent between techniques. For < 6 follicles, three techniques resulted in significantly fewer oocyte/follicle (0.97 ± 0.48, 0.95 ± 0.66, and 0.90 ± 0.41) compared to the top-performing technique (TPT) (1.11 ± 0.55). For 6-10 follicles, two techniques resulted in significantly fewer oocyte/follicle (0.95 ± 0.39 and 0.93 ± 0.35) compared to the TPT (1.06 ± 0.42). A different technique had higher %MII (0.77 ± 0.19) compared to two techniques (0.74 ± 0.21 and 0.72 ± 0.22). For > 10 follicles, two techniques resulted in significantly fewer oocyte/follicle (1.01 ± 0.42 and 1.07 ± 0.40) compared to the TPT (1.15 ± 0.41). These two techniques also resulted in fewer MII/follicle (0.75 ± 0.33 and 0.81 ± 0.34 vs. 0.87 ± 0.34). There was no consistent TPT across follicle number groups or for all outcome variables.

There does not appear to be a clear TPT, even for patients with few follicles. Providers who perform OR in a similar fashion to physicians at our institution should feel confident that those techniques obtain equivalent oocyte yields.