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Published on: December 9, 2015
Seasonal variation in gestational blood pressure
Lisa M Bodnar1, Ashi Daftary, Nina Markovic
1Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA 15261, USA. bodnar@edc.pitt.edu
Objective:
To assess seasonal variability in antenatal blood pressure (BP).
Methods:
We studied 1919 pregnant women who contributed 21,119 antenatal BP measurements.
Results:
BP peaked in winter and reached a nadir in summer. After confounder adjustment, systolic BP was 1.0 to 1.7 mm Hg higher January to May, 0.6 mm Hg higher in September and October, and 0.8 mm Hg higher in November and December compared with August. After stratifying by overweight status, BP showed strong seasonal variability among lean women, whereas there were no seasonal trends among overweight women.
Conclusion:
Environmental factors may regulate gestational BP and may be relevant to seasonality of hypertensive disorders of pregnancy.
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Measurement of Blood Pressure
Factors affecting Blood pressure
Physiological Factors:
Special considerations while measuring blood pressure
Monitoring Both Arms:
Monitoring BP in both arms during the initial assessment is advisable, as the systolic value may differ by five to ten mm Hg between arms. For subsequent BP assessments, use the arm with the higher reading.
Sites for measuring blood pressure
The Brachial Artery: Primary Site for Blood Pressure Measurement
Blood Pressure
Blood Pressure
The average BP in an adult is typically around 120/80 mmHg (millimeters of mercury). In this measurement, the numerator (120) indicates the systolic pressure, which is the pressure in the arteries during the contraction of the heart's ventricles as blood is expelled. The denominator (80) represents the diastolic...
