title: Semi-Fowler's positioning, lateral tilts, and their effects on nonstress tests.
abstract: OBJECTIVE
  To determine whether a lateral tilt for women in semi-Fowler's position for antepartum nonstress tests (NSTs) (a) promotes NST reactivity or (b) shortens testing time required to obtain a reactive tracing.
  
  
  METHODS
  An antepartum fetal assessment unit of a tertiary care facility in eastern Canada.
  
  
  METHODS
  In this prospective, randomized study, a computer analysis of the NSTs was used to obtain an objective, standardized interpretation of fetal heart rate reactivity. Participants were randomly assigned to two experimental groups using semi-Fowler's position with a 45-degree tilt to either the left or right, or to a control group using semi-Fowler's position with no lateral tilt.
  
  
  METHODS
  A convenience sample of 823 nonstress tests was obtained from women with singleton pregnancies, intact amniotic membranes, and gestations between 32 and 42 weeks. The final sample available for analysis totaled 738 nonstress tests from 573 pregnancies.
  
  
  METHODS
  Percentage of reactive nonstress tests and the number of minutes required for tests to be reactive.
  
  
  RESULTS
  The rate of reactive NSTs and the time to achieve a reactive NST did not differ statistically for any of the three study groups. Likewise, NST outcomes were similar when the left-tilt group was compared with the right-tilt group. Although no significant differences were found between study groups, less than 2% of the women in the control group (semi-Fowler's position without a lateral tilt) experienced symptoms consistent with supine hypotensive syndrome.
  
  
  CONCLUSIONS
  No statistically or clinically significant differences were found in nonstress tests between the three groups. Lateral tilting did not shorten test time. Results do suggest that hemodynamic changes can occur in 3rd trimester women who are in semi-Fowler's position without a lateral tilt. Lateral tilting of gravidas in semi-Fowler's position during nonstress testing is thus supported to avoid hypotensive symptoms.
authors.affiliation: School of Nursing, Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: F W
authors.initials: FW
authors.lastname: Moffatt
authors.forename: M
authors.initials: M
authors.lastname: van den Hof
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D005323:Fetal Monitoring / Q000379:methods*; D006340:Heart Rate, Fetal; D006801:Humans; D007022:Hypotension / Q000209:etiology / Q000451:nursing; D016389:Maternal-Child Nursing; D011187:Posture; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000209:etiology / Q000451:nursing; D011446:Prospective Studies; D013997:Time Factors