In this letter, we investigate the effect of chirp, resulting from either t
he transmitter, chromatic dispersion, or Kerr effect in the fiber, on polar
ization-mode dispersion (PMD) compensated systems. We demonstrate both expe
rimentally and numerically the deleterious impact of chirping on systems wi
th first-order PMD compensation. We present a way to optimize the PMD compe
nsator performance by minimizing the total chirp of the signal at the recei
ver side.