The Spanish Fertility Society (SEF) collects statistical data from every fertility clinic in Spain and classifies them in an annual registry.
Success rates after ICSI treatment depend on the age of the woman. Women under 35 years of age have the best prognosis, obtaining a pregnancy rate of 42.8% per transfer.
Women between 35 and 39 years of age have a transfer pregnancy rate of 36.3%. However, this success rate decreases to 20% in women over 40 years of age.