We study string quantum corrections to the ratio of latitude and circular Wilson loops in N = 4 super-Yang-Mills theory at strong coupling. Conformal gauge for the corresponding minimal surface in AdS(5) x S-5 is singular and we show that an IR anomaly associated with the divergence in the conformal factor removes previously reported discrepancy with the exact field -theory result. We also carefully check conformal anomaly cancellation and recalculate fluctuation determinants by directly evaluting phaseshifts for all the fluctuation modes.