The absence of a beneficial effect of FSH was puzzling and unexpected. Indeed, in experiments not shown, we tested several different regimens of FSH treatments, such as different concentrations at different times during the 10-day culture period, and combinations of treatment with FSH and estrogen. Among these conditions we never observed a beneficial effect of FSH on the acquisition of developmental competence. Nevertheless, further testing of potential competence-promoting effects of FSH in combination with other hormones and growth factors is continuing. flovent inhaler

Supplementation of the culture medium with FBS did not prevent the deleterious effects of FSH on oocyte developmental competence, although the suppression was not as dramatic as that observed using serum-free medium. Perhaps no conclusion should be drawn from these negative results. Conditions of culture might preclude the possibility of FSH having a beneficial effect, or oocyte developmental processes might be able to compensate for the absence of FSH, or we may simply have not tested the appropriate combination or concentration of factors to demonstrate the ability of FSH to promote competence to complete preimplantation development. Alternatively, we must weigh the concept that FSH is not a factor that drives development and function of the peri-oocytic granulosa cell in a specific way that is beneficial to oocyte growth and acquisition of developmental competence. Rather, FSH may play only a general role in sustaining these processes in oocytes, i.e., by supporting overall follicular development and endocrine function and by preventing follicular degeneration.