Maternale Endothelfunktion in Schwangerschaft und Wochenbett – ultraschallgestützte longitudinale Erfassung mittels Flow Mediated Dilatation (FMD)

Abstract

NO-triggered vasodilatation decreases peripheral vascular resistance in pregnancy. Using a noninvasive ultrasound technique, flow-mediated vasodilatation can be quantified. We used this technique to detect changes in endothelial function during pregnancy and postpartum. In a prospective longitudinal study 16 healthy pregnant women were assessed for flow-mediated dilatation of the brachial artery during pregnancy (first trimester T1<14th gestational week, second trimester T2 ≥14th-27th gestational week, third trimester T3 ≥28th gestational week) and postpartum (>6 weeks postpartum). As a control group, flow-mediated dilatation was determined in 19 healthy non-pregnant women. Flow-mediated dilatation (%) increased significantly in normal human pregnancy from the first trimester (T1 8.0±5.58 vs. T2 15.2±5.19, p<0.003) to the second trimester and reached its maximum in mid-trimester. Towards the end of pregnancy, flow-mediated dilatation decreased significantly (T2 vs. T3 9.15±3.61, p<0.004). Mean values of flow-mediated dilatation are significantly higher during the second and third trimester of pregnancy compared to non-pregnant controls (T2 vs. NP 6.17±4.39, p<0.001; T3 vs. NP, p<0.047). Postpartum flow-mediated dilatation decreased to values of early pregnancy. During pregnancy maternal endothelial function shows an increase in flow-mediated dilatation and then reverts postpartum. Using ultrasound-based measurement of flow-mediated dilatation, these physiological changes in pregnancy can be reliably detected.