Adrenomedulun by trimester in preeclamptic versus normal pregnancy

OBJECTIVE: Adrenomedullin (ADM) is a newly discovered hypotensive and natriuretic peptide which participates in blood flow regulation. Our purpose is to describe plasma levels for each trimester in normal pregnancy and preeclampsia (PIH). STUDY DESIGN: Of 19 patients initially recruited, 10 healthy, normoteiisive, primigravidas had plasma collected in each trimester of pregnancy and 5 subsequently developed PIH. ADM levels were determined by radioinnmunoassay for human ADM 1-52 (Phoenix pharmaceuticals). Statistics were performed using Mann-Whitney and Friedman tests, and Kendall coefficient of concordance. RESULTS: In normal pregnancy, ADM levels did not differ by trimester and were not correlated. In preeclampsia, levels significantly rose towards term (p = 0.015) and were highly correlated (Kendall = 0.84). Third trimester ADM was significantly increased in PIH (p = 0.04). 1 Trimester 2 Trimester 3 Trimester Mean ±SE Mean ±SE Mean ±SE pg/tnl pg/ml pg/ml Preeclampsia 9.9 ±2.0 15.0 ±1.2 43.9 ±15.8 (N - 5) Normal (N = 5) 8.9 ±1.1 13.3 ±2.9 18.0 ±9.2 CONCLUSION: ADM significantly increases towards term in preeclamptic pregnancies, while there is little change in normal pregnancy. This may represent a compensatory response to the increased vascular tone seen with PIH in the third trimester.