Cryopreservation of spermatozoa and embryos has been a standard procedure in Dutch fertility laboratories for several decades. Until recently, oocyte cryopreservation was rarely performed because of the low chance of survival. 'Vitrification' is a promising new technique for the freezing of oocytes. This ultra-quick freezing method can be used when no spermatozoa, or no viable spermatozoa, could be obtained during in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI), and for patients with cancer who have to undergo potentially damaging oncology treatment. The Academic Medical Center in Amsterdam has performed oocyte vitrification for 20 patients in the period March 2006 - October 2009. Ten of these patients have undergone ICSI treatment; this resulted in three pregnancies and the birth of two healthy babies from two of these pregnancies.