Oocytes of rabbits and mice, successfully cultured in vitro in the first half of the twentieth century, laid the foundation for assisted reproductive techniques decades later. In vitro fertilization (IVF) studies in rabbits resulted in the first birth of a normal offspring in 1959. Since then, advances in experimental reproductive technology, leading to new insights into sperm capacitation, oocyte maturation and sperm-egg interaction, have tremendously increased our knowledge about the fertilization process in humans.