Pulsatile gonadotrophin releasing hormone stimulation after medium-term pituitary suppression in polycystic ovary syndrome.

Ovulation induction in the polycystic ovary syndrome with pulsatile gonadotrophin releasing hormone (GnRH) in the recovery phase after treatment with a GnRH agonist (GnRHa) during 6-8 weeks has been reported to improve ovulation and pregnancy rates and to normalize follicular phase luteinizing hormone (LH) levels. We studied the results of stimulation with pulsatile GnRH after a shorter 'medium-term' period of 3 weeks of treatment with a GnRHa by comparing a cycle without GnRHa pre-treatment with a cycle with GnRHa (post-GnRHa) pre-treatment in 12 patients. We could prove no significant clinical improvement in post-GnRHa cycles. Ovulation rates were similar. However, in the post-GnRHa cycles, two ongoing pregnancies were observed versus one spontaneous abortion in the cycles without GnRHa pre-treatment. This observation might be explained by the fact that follicular phase LH levels in post-GnRHa cycles were significantly decreased.