C-Type natriuretic peptide levels in women with gestational hypertension and preeclampsia

Abstract

Objective: To measure plasma levels of C-type natriuretic peptide in women with normal pregnancies and those complicated by gestational hypertension and preeclampsia. Methods: We collected venous plasma samples from 20 women with normal pregnancies, 15 with gestational hypertension, and nine with preeclampsia. Gestational ages ranged from 26–39 weeks. We measured C-type natriuretic peptide concentrations by radioimmunoassay. Statistical comparisons were made by one-way analysis of variance and Tukey test. Results: The mean plasma concentration of C-type natriuretic peptide in the women with normal pregnancy was 7.1 ± 2.5 pg/mL, in those with gestational hypertension 9.6 ± 4.2 pg/mL, and in those with preeclampsia 8.1 ± 2.4 pg/mL. There were no statistically significant differences between groups. The statistical power to detect a difference of 3 pg/mL at the 5% significance level was 78% for the group with gestational hypertension and 64% for the preeclamptic group. Conclusion: Our results suggest that C-type natriuretic peptide plasma levels are not significantly different in normal pregnancies and those complicated by gestational hypertension or preeclampsia. In hypertensive pregnancy disorders, C-type natriuretic peptide showed a distinct course compared with atrial natriuretic peptide and brain natriuretic peptide.