ABSTRACT
Oocyte growth and quality are dependent on the normal growth and differentiation of the oocyte’s harboring follicle. However, the oocyte itself also plays a direct part in the follicular environment, for example by preventing premature luteinization by regulating the secretion of cumulus mucificationenabling factors, luteinizing hormone (LH) receptor expression on cumulus cells, and kit ligand expression in granulosa cells.1-4 Human oocytes obtained for in vitro maturation (IVM) are aspirated from 6-12-mm follicles, and have not completed their growth and final maturation. Previous work has shown that, during the period just preceding the final meiotic maturation stage, the synthesis and packaging of RNA and translational products are very important processes determining further developmental events.5,6
When retrieving oocyte-cumulus complexes from small antral follicles for IVM, it is our aim to substitute for those intrafollicular maturation conditions which seem to be fundamental for further embryonic development. The small antral follicles which are aspirated for the purpose of IVM have already undergone a growth period of several months, and have moved into a state of gonadotropin dependence.7
