[Hypophyseal suppression and subsequent cycle stimulation: experiences in an in vitro fertilization program]

Gonadotropin releasing hormone (GnRH) agonists can induce a hypogonadotropic state. We studied the effect of a long acting GnRH agonist on pituitary gonadotropin levels, the pattern of serum steroid levels in subsequent cycle stimulation, and whether such a protocol can improve the results of an in-vitro fertilization (IVF) program. 29 patients with tubal factor from our IVF program received 4 mg Decapeptyl CR intramuscularly and were subsequently stimulated with FSH/HMG/HCG (Group I). 35 patients were stimulated according to our standard protocol with HMG/HCG (Group II). After a single injection of Decapeptyl CR, serum levels of LH, FSH and E2 fell to more than half of pretreatment levels. In the subsequent cycle stimulation the gonadotropin dosage was increased threefold compared with the control group. In group I, progesterone levels were significantly higher. Though more oocytes were retrieved in group I, fertilization rates were significantly lower. After Decapeptyl and the subsequent stimulation, we observed short rises in urinary LH in 22/29 patients. In our experience, a single intramuscular injection of Decapeptyl resulted in sufficient pituitary suppression, however, we could not see an improvement in the results after IVF.