Calcium intake during the third trimester of pregnancy was determined in 82 pregnant women by recording the consumption of foods over a 5-day period and by calculation of the quantity of this element provided by dietary supplements. For each subject, blood pressures were measured once per week using an aneroid sphygmomanometer, to detect and analyze differences in calcium intake between those with normal blood pressure and those suffering from gestational hypertension (7.3%). Calcium intake was significantly lower amongst subjects with high blood pressure (757.7 +/- 154.5 compared to 986.4 +/- 502.3 mg/day in normotensive subjects). The relationship between calcium intake and blood pressure was independent of other variables such as body mass index, number of previous pregnancies, weight gain, subject age or hematocrit levels. Though further investigation is needed, the results obtained seem to support the idea that pregnant women should try to maintain an optimal calcium intake.