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.

Objective: 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 > or = 1 year, serum oestradiol (E(2)) < 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.