The use of luteinising hormone releasing hormone and its analogues for induction of ovulation and ovarian stimulation for in-vitro fertilisation.

The use of subcutaneous pulsatile luteinising hormone releasing hormone (LHRH) for induction of ovulation in patients with hypogonadotrophic hypogonadism is efficacious and safer compared to human menopausal gonadotrophin (hMG) because of the lower risk of ovarian hyperstimulation and multiple pregnancy. In clomiphene citrate (CC) nonresponsive cases of polycystic ovarian disease (PCOD), the major advantage of pulsatile LHRH is that when ovulation occurs, it is usually uni-follicular. In cases of PCOD, we have found that if pulsatile LHRH alone fails to induce ovulation, addition of clomiphene citrate or a small dose of follicle stimulating hormone (FSH) will augment its action and allow, in the majority of cases, the threshold of stimulation to be reached that would be sufficient to induce ovulation but not produce clinical hyperstimulation or multiple pregnancy. LHRH analogues to desensitise the pituitary prior to ovarian stimulation with hMG have been recently used in in-vitro fertilisation (IVF). We have compared the use of the LHRH analogue, buserelin (Hoechst, UK) + hMG with clomiphene + hMG for ovarian stimulation in IVF in a number of prospective studies. In this review, the role of pituitary desensitisation in IVF is discussed in the light of our results. We have found that although the mean number of oocytes, the implantation rate and pregnancy rate per embryo transfer are higher in patients who receive buserelin + hMG, the differences are not statistically significant. The length of time taken to achieve pituitary desensitisation is increased in patients who have PCOD or who form ovarian cysts in response to the administration of buserelin.(ABSTRACT TRUNCATED AT 250 WORDS)