Autonomic cardiovascular regulation during pregnancy - interactions and complexity

The assessment of the autonomic cardiovascular regulation can provide important additional diagnostic and prognostic information. The aim of this study was to investigate the alterations of this system in the progress of normal pregnancy applying methods of nonlinear dynamics to characterize the complexity of the heart rate and blood pressure time series. Also the linear and nonlinear interactions between both signals were analyzed. The data of 21 pregnant women at three different gestational stages were analyzed. It was shown that there is a high significant difference between the pregnancy before and after week 25 of gestation. Further on it was proved that the alterations are more pronounced in the first half of pregnancy than in the second half. Especially the parameters of Joint Symbolic Dynamics and correlation methods revealed significant results. On the basis of these information on normal pregnancy conclusions might be drawn to diagnose abnormalities and to avoid serious maternal and prenatal complications.A. Seeck, M. Baumert, and A. Vos