OBJECTIVES: To assess outcomes and treatment costs of a recombinant (rFSH+rLH) and an urinary gonadotropin (hp-HMG) for infertile women over 35 years old in Brazil.  METHODS: A cost per outcome model was developed to assess clinical and economical impact of comparators. It simulates one in vitro fertilization (IVF) cycle with up to four embryo tranfers - one fresh and up to three frozen. Drug acquisition costs were derived from official drug list price in Brazil. Outcomes were derived from a pooled data analysis of clinical trials.  RESULTS: Drug acquisition costs for ovarian stimulation is R$ 5,115 and R$ 3,970 for rFSH+rLH and hp-HMG, respectively. Treatment with either comparator uses approximately 2,760 IU and yields 8 oocytes. rFSH+rLH yields 1,6 more embryos (5,1 vs. 3,5) in average. Cumulative clinical pregnancy rate and cumulative live birth rate are 31% and 24% higher for rFSH+rLH, respectively. Cost per oocyte is R$ 632 and R$ 450 for rFSH and hp-HMG, respectively; cost per embryo is R$ 993 and R$ 1,131; cost per clinical pregnancy is R$ 10,292 and R$ 10,448; and cost per live birth is R$ 24,520 and R$ 24,891.  CONCLUSIONS: In women over age 35, rFSH+rLH yields 47% more embryos, which allows for at least one more frozen embryo transfer, resulting in greater chances of clinical pregnancy and live birth. Despite a greater treatment cost with rFSH+rLH, it is a more efficient gonadotropin than hp-HMG, with savings of R$ 139 per embryo, R$ 157 per clinical pregnancy and R$ 371 per live birth.