Baroreflex control of heart rate is impaired in pre-eclampsia

Autonomic nervous dysfunction, such as parasympathetic and sympathetic impa irment, has been suggested as possible cause of pre-eclampsia, but the stud ies are not conclusive. Our purpose was to assess non-invasively if pre-ecl ampsia is associated with a decreased baroreflex function. Nine women with preeclampsia (PE), eight normotensive pregnant women, and seven healthy nor motensive non-pregnant women were studied. Continuous finger blood pressure was recorded by a Portapres device in the left lateral recumbent position and active standing. Baroreflex gain was evaluated by cross-spectral analys is of systolic blood pressure and pulse interval. The result was that baror eftex gain at rest was lower in pre-eclamptic women both compared to non-pr egnant and healthy pregnant subjects (P < 0.05). Moreover, a decrease of th e baroreflex sensitivity was present in all pregnant women in the orthostat ic position (P < 0.05). In conclusion pregnancy per se is associated with a decrease in the baroreflex control of the heart, whereas in pre-eclampsia, the baroreflex sensitivity is impaired further.