GONADOTROPIN-RELEASING-HORMONE AGONIST AND OVARIAN HYPERSTIMULATION SYNDROME IN ASSISTED REPRODUCTION

The available literature concerning the association between gonadotrop hin-releasing hormone agonist and ovarian hyperstimulation syndrome ha s been reviewed and the different patterns by which this agent may con tribute to the development of such iatrogenic complication has been el icited, and guidelines have been presented for prevention of this mala dy. Gonadotrophin-releasing hormone agonist acts directly on human gra nulosa cells, probably in its own dose-dependent manner. The extent of this action is probably subjected to follicular maturation stage and to the degree of gonadotrophin pre-treatment. Various agonist effects in assisted reproduction may be implicated in the development of ovari an hyperstimulation syndrome: a higher amount of menotrophin; prematur e luteinization prevention; 'flare-up' effect; and a higher pregnancy rate. Different methods for prevention of ovarian hyperstimulation syn drome may be attempted: (i) all embryo cryopreservation with luteal ph ase reinitiation of agonist; (ii) avoidance of ovulatory human chorion ic gonadotrophin (HCG) and continuation of agonist; (iii) cancellation of ovulatory HCG, prolongation of agonist and later recommencement of menotrophin; (iv) pre-ovulatory LH surge triggering by agonist instea d of the conventional HCG. Gonadotrophin-releasing hormone agonist may affect the steroidogenic ovarian stroma directly and such interaction may aggravate the development of ovarian hyperstimulation syndrome.