Effects of Growth Hormone on Adult Human Gonads: Action on Reproduction and Sexual Function

Figure 2

GH/IGF-1 roles in reproduction of adult females and potential mechanisms. Systemic GH/IGF-1 stimulates ovarian IGF-1 production. GH of ovarian origin is not fully confirmed and is not shown in the figure. Systemic GH/IGF-1 and/or ovarian IGF-1 play roles. They contribute to the recruitment of primordial follicles and promote the growth and development of follicles. They are able to improve the FSH action on the granulosa cell and promote the LH action on the theca cell. Subsequently, steroidogenesis is ameliorated. They can also induce ovulation and support the maturation process of luteinization. The effect of GH/IGF-1 on the endometrium is to improve endometrial receptivity. GH/IGF-1 can also contribute to an increase in endometrial receptivity by raising estrogen levels. GHR: growth hormone receptor; IGF-1R: insulin-like growth factor-1 receptor; LHCGR: luteinizing hormone/choriogonadotropin receptor; FSHR: follicle-stimulating hormone receptor.