Flame-sampling experiments allow describing the species profiles as function of the height above the burner. However, the so-measured species profiles are perturbed by the heat losses due to the probe, and/or species losses inside the probe. In order to attempt to clarify the perturbations induced by a microprobe, NO species profiles were obtained in a stoichiometric low-pressure flame by using in situ and ex situ measurements. An unperturbed NO species profiles was measured locally by LIF. Two shapes of microprobes were used to perform ex situ measurements by CRDS after gas probe sampling. The comparison of the profiles shows that the profiles obtained after probe sampling are shifted downstream, and that the absolute mole fraction of NO may be drastically affected during the sampling.