Blood pressure in late pregnancy and work outside the home

Objective: To assess maternal blood pressure (BP) responses to working outs ide the home in late pregnancy, using 24-hour ambulatory BP monitoring. Methods: Our paired observational study involved 24hour ambulatory BP monit oring of 100 normotensive women (51 primiparas, 49 multiparas) on work and nonwork days. Mean BP differences were calculated for working, postworking, sleeping, and 24-hour periods on both days. Main outcome measures were BP differences between work and nonwork days and subsequent pregnancy hyperten sion. Comparisons in BP between work and nonwork days were done with Studen t paired t test. Comparisons between study subgroups were done with unpaire d t test. Potential predictors of change in BF were examined using multiple linear regression. Results: During job time, BP was significantly higher on work days than on nonwork days. The mean increase in BP associated with work was 2.6 mmHg (sy stolic BP, P < .001), 2.8 mmHg (diastolic BP, P < .001), and 2.9 mmHg (mean arterial BP, P < .001). Those observations were independent of parity. Mor e than 10% of our subjects had increased mean arterial BP of 10 mmHg or mor e during job time on work days compared with nonwork days. Higher absolute BP levels (regression coefficient 0.21, P = .04) and greater perceived job stress (regression coefficient 1.34, P = .04) correlated positively with BP increases at work. Twelve women developed hypertension. Those women had a larger increase on work days in mean systolic (6.6 mmHg compared with 2.1 m mHg, P = .013), mean diastolic (6.4 mmKg compared with 2.3 mmHg, P = .014), and mean arterial (7.4 mmHg compared with 2.3 mmHg, P = .002) BP compared with normotensive women. The magnitude of BP responses to work was a signif icant predictor of pregnancy hypertension, independent of absolute BP level . Conclusion: Blood pressure increased in women when they worked outside the home. The effect of maternal work is important when treating pregnancy hype rtension. Ambulatory BP monitoring makes assessment of maternal BP response s to work a practical clinical option. (C) 2001 by The American College of Obstetricians and Gynecologists.