Hematologic values, including concentrations of iron and folate in blood were studied in pregnant women and in a group of patients in the puerperium period, and compared with those in a group of non-pregnant women. Except for red cell folate, which was low in all groups, and total iron binding capacity, which was high in the pregnant and puerperium groups, the mean values for all other parameters studied were within normal limits. Thirty-six percent of the pregnant and 38% of the puerperium patients, were found to be anemic, while no anemia was recorded in the non-pregnant group. In the anemic group, combined iron and folate deficiency was the most common finding (30% and 36%), followed by isolated iron deficiency in pregnant patients (17%), and serum folate deficiency alone in puerperium group (27%). In the iron anemic group, low folate values were most frequent in the pregnant and puerperium patients. In the latter there was a frequency of 22% and 44% of serum and red cell folate deficiency respectively, while in the non-pregnant patients frequency of iron deficiency was higher (13%). No correlation was found between hemoglobin and folate concentration. A good correlation was encountered between hemoglobin and the transferrin saturation index. A significant correlation between neutrophil hypersegmentation and folate was found only in iron-deficient patients, although low folate generally corresponded to increased neutrophil lobe average.