Received February 02, 2014
Accepted February 12, 2014

Dear Editor-in-Chief The article published in your prestigious journal by Vieira and Colucci (2013) had been carefully read by our group. We agreed that any assisted reproductive technique gave stress in the couple and it would be higher in women in comparison to men. However, in the mentioned paper were found some remarkable mistakes resulting in conclusions which are not supported by data. First, the reported results have a serious methodological bias since it was not a randomized study. Then, as the baseline patient characteristics were not presented, we don not know if groups were comparable (IVF-ICSI treatment and INVO treatment). The psychological characteristics of the patients before ART were not shown. Second, the study did not show any power analysis and more importantly no statistical comparisons were performed. This is the main problem since conclusion was based on different response to stress in patients treated either by INVO or ICSI. However, the row data included in the article support a statistical analysis by using Fisher exact test, if the authors would have performed such analysis no differences (p=0.5273) would have been observed between the studied groups. Consequently, any statement arguing differences between the two techniques can be drawn. Finally, the authors did not mention the clinical outcomes in patients underwent either ICSI or INVO treatment.