PURPOSE: to show longitudinally the profiles and parameters of pressure rhythm and heart rate in normotensive pregnant women during the three trimesters of pregnancy. PATIENTS AND METHODS: the longitudinal and random study involved 23 normotensive pregnant women, mean age 23.3 ± 3.9 years, recruited from the prenatal clinics of the "Maternidade-Escola Hilda Brandão - Santa Casa de Belo Horizonte/MG". Ambulatory blood pressure monitoring was done every three months (up to 14 weeks, between 18 and 28 weeks and between 32 and 40 weeks, using the SpaceLabs monitor, model 90207. RESULTS: a significant increase (p<0.01) in the 24-h systolic (115 and 104 mmHg), diastolic (73 and 61 mmHg) and average diurnal and nocturnal blood pressures (87 and 77 mmHg respectively), was noticed in the third trimester of pregnancy. Mother's diurnal blood pressure and heart rate (83, 84 and 87 mmHg; 94, 95 and 93 bpm) were significantly higher than the nocturnal measurements (72, 72 and 77 mmHg; 74, 79 and 79 bpm), in the three trimesters. Mother's heart frequency did not change during progress of pregnancy. CONCLUSION: increase in blood pressure during the third trimester of pregnancy could be shown. Maternal daily and diurnal heart rate did not change when the three trimesters were compared. The nocturnal heart rate was significantly lower in the first trimester as compared to the other trimesters.
Ambulatory blood pressure monitoring; Circadian rhythm; Heart rate; Pregnancy
