We review the results of our looking for line profile variations (lpv) in spectra of selected OBA stars. The regular variations of the line profiles with periods ranging from several hours to days in spectra of all program stars were detected. Recent observations of selected stars using FOcal reducer low dispersion spectrographs FORS 1 and FORS 2 in spectropolarimetric mode mounted on the 8-m telescopes of the VLT show the strong line profile variations (lpv) in spectra of magnetic OBA stars. We also reveal the moderate line profile variations of various lines on a time-scale of minutes or maybe even a fraction of a minute in FORS 2 spectra of the A0 supergiant HD 92207. The possibility of such short time-scale lpv for OBA stars was recently confirmed by our high time resolution spectra observations spectra of HD93521 with the multi-mode focal reducer SCORPIO at the BTA. The presence of short-term spectral variability in massive OBA stars, which are proposed to be the progenitors of Type II supernova was not studied systematically studies before and can be critical for the current theoretical understanding of their physics. The short-term periodicity did not known earlier for non-radially pulsating supergiants and its confirmation is of great importance for modeling the stellar evolution.

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