Summary Scheel et al. [1] highlight three types of methodological concern with the work reported in our recent paper [2], related to analytical decisions, fetal behavior, and how light interfaces with maternal tissue. Here we outline why the issues raised do not detract from our originally reported conclusions. In our view, the procedural and analytical decisions that we made in our study [2] were the most appropriate given the uncharted territory that we explored. The best test of methodological robustness of our approach would be replication by another laboratory.