Abstract
PURPOSE: The aim was to compare the follicular response to 37.5 and 50 IU of recombinant follicle-stimulating hormone (FSH) as starting doses for ovulation induction in patients with polycystic ovary syndrome (PCOS). METHODS: Prospective, randomized, crossover study including 15 women with clomiphene citrate-resistant chronic anovulatory infertility. Patients were treated with subcutaneous recombinant FSH at starting doses of 37.5 IU and 50 IU, respectively, according to a low-dose step-up protocol. Each woman received both treatments, in a randomized order, with an interval of > or = 1 month between treatments. RESULTS: All treatment cycles were ovulatory after an appropriate follicular response and hormone levels were similar with both treatments, although the total quantity of FSH required and the mean daily dose required to induce identical follicular development were significantly lower with a starting dose of 37.5 IU FSH. The mean duration of treatment to achieve ovulation was approximately 13 days with both treatments but treatment periods > or = 20 days were required in some patients. CONCLUSIONS: In women with PCOS, a starting dose of 37.5 IU recombinant FSH may be adequate to induce follicular growth. However, the use of low starting doses may result in some cases in increased treatment periods and need for monitoring.