Objective: To assess the effect of gonadotropin-releasing hormone agonist (GnRH-a) on pituitary suppression, subsequent ovarian response, and results of in vitro fertilization (IVF) treatments in polycystic ovarian syndrome (PCOS) patients.
Design: Randomized prospective study.
Setting: In vitro fertilization program and endocrinologic institute.
Patients: Thirty patients with PCOS; 16 received GnRH-a, and 14 did not receive GnRH-a.
Interventions: Ovum pick-up and embryo transfer.
Main outcome measures: Response to GnRH-a test, serum and follicular fluid (FF) hormonal measurements, steroid levels, and aromatse activity in granulosa cell (GC) culture, and results of IVF.
Results: Pituitary responsiveness was abolished in all patients 14 days after GnRH-a administration, and early luteinization was prevented. Steroid levels in FF did not differ between the two groups. In GC culture, progesterone (P) levels were higher in patients without the GnRH-a (3,704 +/- 1,232 nmol/L versus 2,117 +/- 235 nmol/L; P less than 0.05) as were androstenedione (A) levels (5.3 +/- 1.0 nmol/L versus less than 3.5 nmol/L; P less than 0.05). However, aromatase activity and IVF results were similar in the two groups.
Conclusions: Administration of GnRH-a in patients with PCOS decreases P and A production by the GC cells and prevents early luteinization. It does not affect the IVF results.