Judging the Fertility Protective Effect of GnRH Agonists in Chemotherapy—It Is a Matter of Perspective

The efficacy of GnRH agonists (GnRHa) as a method for protecting fertility has been controversially discussed for years. This is clearly demonstrated by the fact that there are now more meta-analyses on this subject than individual studies. However, the discussion is often not conducted objectively but seems to be shaped by fundamental ideologies, leading to a scientific dispute between GnRHa advocates and GnRHa opponents. A new study now adds even more fuel to the fire of the discussion because it investigated the long-term protective effect of GnRHa on the ovaries for the first time and was not able to demonstrate a long-term effect (1). Based on this, it is not time for us to evaluate the overall effectiveness of GnRHa, or even allow ourselves to be led by ideologies, but to consider the existing studies and their target criteria in an objective and differentiated manner. Different criteria were defined in the study which, due to their diversity, has the disadvantage that the studies cannot be evaluated in the same way and is certainly one of the reasons for the controversial data situation. On the other hand, this has the great advantage that due to the different target criteria, different aspects of GnRHa effects have been analyzed, and the effectiveness of GnRHa can therefore be assessed from different perspectives. In the studies, the following criteria were defined to assess the effect of GnRHa: