Low-dose FSH stimulation in polycystic ovary syndrome: comparison of 3 FSH-preparations.

In patients with PCOS low dose administration of follicle stimulating hormone is accepted as a safe treatment modality with low risk for an ovarian hyperstimulation syndrome or a multiple pregnancy. In this study we have retrospectively compared the efficacy of 3 different FSH preparations in low dose protocols-urinary FSH (FSH), highly purified urinary FSH (FSHHP) and recombinant FSH (rec. FSH). A total of 68 PCOS-patients, 36 lean and 32 moderately obese patients, were treated in 116 stimulation cycles. The mean age did not differ between the groups. A mean number of 1.7 cycles per patient was performed. PCOS was diagnosed in all patients by hormonal and sonographic means. Treatment was performed with daily injections of one ampoule FSH from day 3 onwards. Ovulation was induced with 10,000 IU HCG, when the leading follicle exceeded 16 mm in diameter and no more than 3 follicles were seen. The rate of monofollicular cycles was lowest in obese patients after FSHHP stimulation (30%) and after rec. FSH (66.6% in lean and 58.3% in obese patients, respectively). The number of FSH ampoules did not differ significantly between the groups. No severe hyperstimulation syndrome was registered. 21 pregnancies were achieved without significant differences between the different FSH preparations. Besides two abortions and one ectopic implantation, 12 pregnancies were ongoing singleton pregnancies, 3 twin pregnancies and 3 sets of triplets were noted. In conclusion, low-dose stimulation with FSH offers a safe and successful treatment option in patients with PCOS with an acceptable risk for multiple gestations.