Ambulatory BP monitoring and clinic BP in predicting small-for-gestational-age infants during pregnancy.

The significance of ambulatory blood pressure (ABP) monitoring during pregnancy has not been established. We performed a prospective study to elucidate whether ABP measures are associated with small-for-gestational-age birth weight (SGA). We studied 146 pregnant women who were seen for maternal medical checkups or suspected hypertension. ABP monitoring was performed for further assessment of hypertension. The outcome measure was SGA. The subjects were classified by their medical history and ABP as having preeclampsia or gestational hypertension (n=68 cases), chronic hypertension (n=48) or white-coat hypertension (n=30). There were 50 (34.2%) cases of SGA by the fetal growth reference standard. In multivariable logistic regression analyses adjusting for age, body mass index, the presence of prior pregnancy, current smoking habit and the use of antihypertensive medications, 24-h SBP (per 10 mm Hg (odds ratio (OR): 1.74; 95% confidence interval (CI): 1.28-2.38; P<0.001)) was more closely associated with SGA than clinic BP (OR: 1.40; 95% CI: 0.92-2.13; P=0.11). The results were essentially the same if 24-h BP was replaced by awake or sleep SBP. Ambulatory diastolic BP showed the same tendency. However, abnormal circadian rhythm was not associated with the outcome. In conclusion, ambulatory BP monitoring measures performed during pregnancy were more closely associated with SGA than clinic BP.

PP111. The preceding features before onset of gestational hypertension and preeclampsia in home blood pressure monitoring: The existence of the inflection point and the rapid increased speed of blood pressure.

INTRODUCTION: It has not been clarified whether home blood pressure monitoring (HBPM) during pregnancy is useful to detect high risk pregnant women with later onset of gestational hypertension (GH) and preeclampsia (PE). OBJECTIVES: We thought to determine the preceding features of blood pressure (BP) in HBPM before the onset of GH and PE. We especially focused on the existence of the inflection point, its level, when it occurs, and the increased speed of BP after the inflection point. We compared these features in normal pregnant women (NP), women with GH, and women with PE. METHODS: In this prospective cohort study, 361 singleton pregnant women, among them 100 women recruited due to high risk for GH/PH in the second trimester, participated in a couple of tertiary perinatal centers between 2008 and 2010. HBPM were measured with the validated OMRON HEM-5001(R) automated digital oscillometric sphygmomanometer (OMRON Healthcare Japan). The device was programmed to take three consecutive readings at 15-second interval. HBPM was measured twice a day, at the time of awakening and sleep, through the first to third trimester, and the average systolic blood pressure (SBP) and diastolic blood pressure (DBP) of each gestational week (almost 42 times a week) were calculated. We defined the data of HBPM which started before 28 gestational weeks and continued until 2 weeks before the onset of GH/PE or delivery are eligible. The increased speed of systolic or diastolic BP after the inflection point was defined as ("BP at the onset in GH/PE or at delivery in NP" - "BP at the inflection point") / ("Gestational weeks at the onset in GH/PE or at delivery in NP" - "Gestational weeks at the inflection point"). If there was no inflection point in HBPM, the increased speed of BP was defined as zero. The comparisons were performed using one-way analysis of variance (ANOVA) followed by multiple comparison. Data were shown as mean±SE. RESULTS: A total of 17 (4.7%) women developed PE, and 12 (3.3%) GH.The systolic blood pressure (SBP) levels at the inflection point in NP, GH and PE was 102.4±1.3, 118.7±2.9 and 117.4±2.2mmHg, respectively (Significant pairs: NP < GH, PE); the diastolic blood pressure (DBP) levels at the inflection point was 59.2±1.0, 74.5±2.0 and 73.1±2.0mmHg, respectively (NP < GH, PE). The inflection point in NP, GH and PE occurred at 31.3±0.9, 28.4±1.5 and 22.3±1.4weeks, respectively (PE < GH, NP). The increased speed of SBP in NP, GH and PE was 1.2±0.1, 3.0±0.4 and 4.7±0.7mmHg/wk, respectively (NP < GH, PE); the increased speed of DBP was1.1±0.1, 2.1±0.3 and 2.8±0.4mmHg/wk, respectively (NP < GH, PE). CONCLUSION: In women with later onset of GH/PE, the BP level at the inflection points was higher than in NP. The average inflection point in PE was earlier gestational weeks than in GH and NP. The average increased speed of blood pressure after the inflection point in GH/PE was faster than in NP. The preceding features of BP in HBPM may be clinically useful to detect high risk women with later onset of GH/PE.