Comparison of the effects of HMG or pure FSH stimulation during suppression with an LHRH agonist analogue.

Infertile patients who responded poorly in an in-vitro fertilization programme were treated with human menopausal gonadotrophin (HMG) or with pure follicle stimulating hormone (FSH) during continuous administration of a luteinizing hormone-releasing hormone (LHRH) agonist, to determine whether a low level of LH is required for follicle maturation. No statistically significant differences were detected in the dose of gonadotrophins, duration of treatment, oestradiol and LH levels, numbers of recovered oocytes, transferred embryos or fertilization rates. It is concluded that an absence of low levels of LH does not disturb follicular development in the follicular phase. Based on the low fertilization rates in the present study (0.32 with HMG versus 0.45 with FSH) the authors suggest that, as well as hormonal deficiency, other factors may also influence follicular and early embryonic development.