645 Effects of position on blood pressure measurement in pregnancy

Abstract

ANOVA, chi square, and regression analyses, adjusting for body mass index (BMI), fetal sex, and gestational age at sample collection. RESULTS: 1475 patients were included. Mean gestational age was 14.3 (AE4.4) weeks and mean BMI 26.9kg/m2 (AE6.7). Overall, 3% (N¼42) had a documented AID, with 25 on no therapy and 17 on IM therapy. There was a significant stepwise decrease in mean FF, with 12.0%, 10.4% and 9.6% in the control, AID on IM therapy, and AID on no therapy groups, respectively (p¼0.03) [Figure 1A]. An inverse relationship was observed in the rate of indeterminate results from 3% to 6% to 24% for controls, AID on IM therapy, and AID on no therapy, respectively (p<0.001) [Figure 1B]. Logistic regression showed an increased odds of an indeterminate result for women with AID on no therapy compared to controls, OR 9.1 (95%CI 3.2, 25.7). Linear regression showed a significant decrease in FF for women with AID on no therapy compared to controls, b -2.0 (95% CI -3.8, -0.2). CONCLUSION: Women with AID on no therapy have higher rates of indeterminate cfDNA results compared to controls. Treatment of AID with IM therapies may improve FF, which could be further evaluated in future studies.