Research question
How do platelet-rich plasma products like human platelet lysate (HPL) and umbilical cord plasma (UCP) affect the growth and survival of isolated human pre-antral follicles in vitro?

Design
Human pre-antral follicles (n = 724; mean diameter: 75 µm; range: 46–237 µm) were isolated from ovarian medulla donated by 14 patients undergoing unilateral oophorectomy for ovarian tissue cryopreservation. Follicles were encapsulated in 0.5% alginate and cultured for 8 days in media supplemented with 5% fetal bovine serum (FBS) (n = 171), 2.5% human serum albumin (HSA) (n = 159), 5% HPL (n = 223) or 5% UCP (n = 171).

Results
The survival probability was significantly higher in the group supplemented with HPL (80%) compared with the other three groups: FBS (54%, P < 0.001); HSA (63%, P = 0.004) and UCP (29%, P < 0.001). Surviving follicles in the UCP group had less defined follicular membranes and decompacted granulosa cell layers. The median growth of surviving follicles was significantly (P < 0.001) larger in the HPL group (73 µm) compared with any of the other three groups: HSA (43 μm); FBS (40 μm) UCP (54 μm). A descriptive analysis of follicular secretion of anti-Müllerian hormone and oestradiol did not reveal any difference between the groups. The detectability of follicular genes was high for AR (100%), AMHR2 (100%) and FSHR (76%), whereas few follicles expressed LHR (20%).

Conclusion
Human platelet lysate significantly improved survival and growth of cultured human pre-antral follicles compared with FBS, HSA and UCP. The use of HPL is a valuable improvement to culture human pre-antral follicles but further studies will have to prove whether the superiority of HPL translates into better quality oocytes.