This is a prospective, open-label, non-comparative, multicentric Phase 4 study to evaluate the ease of use, local tolerance, safety and effectiveness of Gonal-f® (filled-by-mass in a prefilled pen) in subjects undergoing ovarian hyperstimulation for in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) with recombinant follicle stimulating hormone (r-FSH).