Follicle-stimulating hormone (FSH) is a heterodimeric glycoprotein consisting of noncovalently linked α and β subunits. It stimulates the growth of immature follicles in ovaries and primary spermatocytes in testes and thus plays an important role in human reproduction (1). Human menopausal gonadotropin for infertility treatment was first introduced into clinical practice in 1950 (2, 3). Subsequently, treatments with urinary FSH have been replaced by recombinant human FSH (rh-FSH), which has been shown to provide several advantages such as absence of…