Low-temperature thermal conductivity measurements have been conducted on an oxygen-annealed single crystal of ${\mathrm{Yb}}_{2}{\mathrm{Ti}}_{2}{\mathrm{O}}_{7}$ from 60 mK to 50 K and in magnetic fields up to 8 T applied in the [111] crystallographic direction. The temperature dependence of the conductivity in zero field shows a significant peak in thermal conductivity at $T\ensuremath{\sim}13$ K and a sharp anomaly at ${T}_{c}\ensuremath{\sim}0.2$ K suggesting that the sample's behavior is representative of the high-purity limit, with low levels of disorder. The magnetic field dependence of the thermal conductivity close to ${T}_{c}$ reveals a reentrant magnetic phase for a field in the [111] direction. With this information, analysis of the very low magnetic field behavior of the thermal conductivity suggests the presence of significant fluctuations close to the phase line.