We studied 150 women with primary/secondary amenorrhea and/or oligomenorrhea; in 61 cases we found an abnormal karyotype (i.e. 40.7%): 51 cases in the first group of 110 patients with amenorrhea (i.e. 46%) and 10 cases in the second group of 40 patients with oligomenorrhea and/or secondary amenorrhea (i.e. 25%). The chromosome aberrations we found consisted in X aneuploidy, male karyotype and the different structural changes as mono- and dicentric X isochromosomes, dicentric, ring, deleted or inverted X chromosomes. Our results suggest a cytogenetic examination in patients with primary amenorrhea as well as in patients with oligomenorrhea and/or amenorrhea secundaria.