The rationale of growth hormone (GH) administration during controlled ovarian stimulation (COH) in in vitro fertilization (IVF) is based on the assumption that increased serum concentrations of GH increases the secretion of insulin-like growth factor 1 (IGF-1) by the ovary, leading to a cascade of intrafollicular events which all converge to promote oocyte development and maturation. Recombinant human GH (hGH) is believed to be safe when it is used in the paediatric management of growth insufficiency and adult growth hormone deficiency. Adult GH-deficient patients treated with hGH experience decreased body fat, increased muscle mass, energy levels, bone density and sexual function, and improved immune system function. More studies of better quality and larger size are required to increase the overall confidence that the addition of hGH to COH really improves the healthy take-home baby rate, the outcome that matters most to IVF patients.