Lessons learned from introducing an in-vitro maturation programme into clinical practice

The technology of in-vitro maturation (IVM) aims at maturing immature oocytes from the germinal vesicle (GV) stage to the metaphase 2 stage of the second meiotic division in vitro. Gametes are obtained by immature oocyte retrieval from small antral follicles (5–12 mm) present in polycystic ovarian syndrome patients or at the beginning of each cycle of normally menstruating woman. Maturation time in vitro takes about 28–36 h. After precise patient selection and adequate preparation, a high proportion of oocytes are able to resume meiosis in vitro. Intracytoplasmic sperm injection is the preferred method of fertilization. About 300 children have been born worldwide after IVM, and are reported to be healthy. Recent data suggests that IVM has the potential to replace standard ovarian stimulation in the near future. Nevertheless, several aspects of IVM regarding safety and efficacy remain unanswered and will have to be addressed. This paper reviews data concerning IVM in clinical practice and describes experience from the establishment of an IVM programme that resulted in the first IVM pregnancy in Germany.