['To assess the relationship between congenital uterine malformations and blood pressure in pregnancy.', 'Twenty-four-hour automated ambulatory blood pressure monitoring (readings every 30 min) was performed in 16 normotensive, nonproteinuric, primigravidae with congenital uterine malformations (5 uterus septus, 9 uterus bicornis, 2 uterine didelphys) between 20 and 30 weeks. From the 24-hr blood pressure report, we calculated 24-hr mean, daytime and nighttime means. The results were compared with 16 primigravidae, matched for age and gestation, who were and remained normotensive throughout pregnancy, and tested for statistics with t-test; significance assessed at p < 0.001.', 'Although they were within the normotensive range, all blood pressure measurements considered were significantly higher in pregnant women with congenital uterine malformations, compared to normal pregnant women. Namely, 24-hr, daytime, and nighttime systolic (mean +/- SD) were 121.1 +/- 8.4, 124.4 +/- 8.8, 114.0 +/- 7.7 mmHg, respectively, in women with uterine malformations and 108.0 +/- 7.4, 109.2 +/- 7.3, 102.1 +/- 8.5 mmHg, respectively, in normal pregnant women. Twenty-four-hour diastolic, daytime, and nighttime diastolic (mean +/- SD) 74.1 +/- 10.2, 77.1 +/- 10.6, 68.1 +/- 9.2 mmHg, in women with uterine malformations and 64.1 +/- 5.7, 66.0 +/- 5.7, 58.2 +/- 6.3 mmHg, in normal pregnant women (all differences p < 0.001). Fifteen of the fetuses from women with congenital uterine malformations showed intrauterine growth retardation. No differences were found 6 months after delivery.'] Are congenital uterine malformations associated to increased blood pressure in pregnancy?