VASCULAR MATERNAL REACTIVITY AND NEONATAL SIZE IN NORMAL PREGNANCY

Abstract

Objective. The purpose of the present study was to determine the associations of cold pressor test (CPT) cardiovascular reactivity with gestational age at birth and neonatal size in normotensive pregnant women.Methods. Seventy (70) healthy pregnant women were enrolled. The CPT consisted of introducing the patients' hands in cold water (4°C) for 3 min. An automatic oscillometric device was used to record blood pressure (BP) every minute for the following 5 min. Perinatal results were correlated with CPT findings.Results. Vascular reactivity assessed by CPT was higher in pregnant hypertensive women and in women with a hypertensive family history. Mean BP increases caused by CPT showed a significant negative correlation for gestational age (r = −0.58, p < 0.001) and cephalic perimeter (r = −0.57, p = 0.03). Diastolic BP increases caused by CPT were negatively correlated with newborn weight (r = −0.78, p < 0.001). Predictable newborn weight, gestational age, and cephalic perimeter were 4046 (47 × diastolic BP increase), 40.2 (0.07 × mean BP increase), and 35.8 (0.09 × mean BP increase), respectively.Conclusions. Results show that every mm Hg diastolic BP increase in response to CPT was correlated with a 47-g decrease in the newborn normal weight. Furthermore, every mean mm Hg BP increase in response to CPT was associated with a 0.07-week decrease in the newborn normal gestational age and a 0.09-cm decrease in the normal cephalic perimeter at birth.