title: Heart rate variability changes in pregnant and non-pregnant women during standardized psychosocial stress.
abstract: OBJECTIVE
  To test the reactivity of the autonomic nervous system (ANS) of women in different stages of pregnancy to a psychosocial stressor.
  
  
  METHODS
  Psychosocial stress was induced by a standardized test, the Trier Social Stress Test.
  
  
  METHODS
  University of Zurich, Switzerland.
  
  
  METHODS
  Fifty-five healthy pregnant women (28 in the second and 27 in or close to the third trimester) and 24 non-pregnant women in the follicular phase of the menstrual cycle.
  
  
  METHODS
  Heart rate variability (HRV) was recorded before, during and after the test. Subjective stress perception was measured by a visual analog scale.
  
  
  METHODS
  Heart rate, HRV components (high frequency, HF; low frequency, LF, and LF/HF ratio), subjective stress ratings.
  
  
  RESULTS
  HF significantly decreased and LF/HF ratio increased during psychosocial stress in all three groups. LF values indicated no significant reaction to psychosocial stress, but a trend towards significance with group interaction was seen. There were no significant differences in subjective stress ratings between the groups.
  
  
  CONCLUSIONS
  ANS activity during psychosocial stress seems to be decreased in proceeding pregnancy, whereas subjective stress perception does not show significant changes. The decline of HF due to stress compared to non-pregnant women is not attenuated, just on a lower level.
authors.affiliation: Department of Obstetrics, University Hospital of Zurich, Zurich, Switzerland.
authors.forename: Ariadne V
authors.initials: AV
authors.lastname: Klinkenberg
authors.forename: Urs M
authors.initials: UM
authors.lastname: Nater
authors.forename: Ada
authors.initials: A
authors.lastname: Nierop
authors.forename: Aliki
authors.initials: A
authors.lastname: Bratsikas
authors.forename: Roland
authors.initials: R
authors.lastname: Zimmermann
authors.forename: Ulrike
authors.initials: U
authors.lastname: Ehlert
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D019540:Area Under Curve; D001341:Autonomic Nervous System / Q000502:physiology*; D016022:Case-Control Studies; D003943:Diagnostic Techniques, Neurological / Q000592:standards*; D005260:Female; D005865:Gestational Age; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008597:Menstrual Cycle / Q000502:physiology / Q000523:psychology; D011247:Pregnancy; D011336:Probability; D011584:Psychology; D012016:Reference Values; D012680:Sensitivity and Specificity; D013315:Stress, Psychological; D055815:Young Adult