Clinics Retrieving Too Many Eggs From IVF Patients, Study Suggests Big Fertility Project 4 years ago Clinics retrieving too many eggs from IVF patients, study suggestslinics may be retrieving far too many eggs from IVF patients, a new study suggests. Researchers say studies indicate the optimal and safe number of oocytes – immature eggs – needed for achieving an ongoing pregnancy is between six and 15.