The development of recombinant follicle stimulating hormone (rFSH) for use in the treatment of infertility: new solutions to old challenges

Recombinant follicle stimulating hormone (rFSH) has been in use in the management of infertility for the past decade. It is a virtually pure compound, with excellent batch-to-batch consistency and the ability to be produced in almost limitless quantities. A historical perspective leading to the development of recombinant products will be discussed, including a review of the two-cell, two-gonadotrophin theory of folliculogenesis. The two currently available recombinant follicle stimulating hormones (follitropin α and follitropin β) will be compared with each other and with urinary follicle stimulating hormone (uFSH) preparations. This comparison will highlight their safety, efficacy and side effect profiles. The use of recombinant follicle stimulating hormone in the special cases of polycystic ovarian syndrome and hypothalamic amenorrhea will be detailed. Finally, future directions in recombinant therapy will be considered, including the creation of long-acting preparations, the development of recombinant luteinizing hormone, and the potential future availability of more convenient administration systems.