Follicular development induced by recombinant luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in anovulatory women with LH and FSH deficiency: evidence of a threshold effect

ABSTRACTObjective: To assess the requirement for luteinizing hormone (LH) in women deficient in LH and follicle-stimulating hormone (FSH).Research design and methods: A prospective, randomized, parallel-group, multicentre study was carried out in tertiary care and academic medical centres. Women with anovulatory amenorrhoea ≥ 1 year, serum oestradiol (E2) < 60 pg/mL (< 220 pmol/L) and low normal serum gonadotrophins were randomized in cycle A to a fixed daily dose of recombinant human (r-h) FSH (150 IU) and r-hLH 0, 25, 75 or 225 IU. Cycles B and C were not randomized.Main outcome measures: Follicular development, ovulation and luteinization.Results: In cycle A, follicular development was achieved by 63.6% (7/11), 100% (9/9), 72.7% (8/11) and 66.7% (6/9) of patients who received r-hFSH and r-hLH 0, 25, 75 or 225 IU/day, respectively ( p = not significant). Among patients with basal serum LH of < 1.2 IU/L, a dose-response relationship of r-hLH to follicular development was observed ( p = 0.039). Fourteen o...