Studies indicate that the optimal and safe number of oocytes needed for achieving an ongoing pregnancy is between six and 15. However, the use of egg freezing, frozen embryo replacement (FER) cycles and aggressive stimulation regimes has increased this number in order to boost success rates in older women and in poor responders who produce fewer eggs. What is not known is the impact of numbers of eggs retrieved and of over-stimulation practices on the health of patients, and on their emotional and financial well-being.