title: Transient accelerations of fetal heart rate analyzed by computerized cardiotocography in the third trimester of pregnancy.
abstract: OBJECTIVE
  The aim of this study was to investigate the patterns of transient FHR accelerations (10 bpm and 15 bpm) in the third trimester of pregnancy, comparing the occurrence of this event before and after the 32nd gestational week.
  
  
  METHODS
  This is a prospective study comparing the results of the computerized cardiotocography of 46 low-risk women with singleton pregnancies, maternal age between 18 and 40 years, gestational age between 28 and 40 weeks, absence of maternal morbidity and adequate fetal growth according to ultrasound. Computed Cardiotocography (8002 Sonicaid System and Fetal Care System) was performed for 30 minutes to analyze the variables of FHR.
  
  
  RESULTS
  Twenty-three pregnant women underwent cardiotocography before 32 weeks (mean = 29.9 weeks, SD = 1.4 weeks) and were compared with 23 pregnant women who were examined after 32 weeks (mean = 36.3 weeks, SD = 2.5 weeks). Regarding the characteristics of FHR, fetuses evaluated between 32 1/7 weeks and 40 weeks showed a significantly greater number of accelerations above 15 bpm (median = 5, variation 0-18) than the group of pregnant women from 28 to 32 weeks (median = 4, variation 0 to 10; P = 0.048). There was a significant positive correlation between the number of accelerations above 15 bpm and the gestational age at examination (rho = 0.33; P = 0.026).
  
  
  CONCLUSIONS
  Computerized cardiotocography showed an association regarding the number of transient accelerations greater than 15 bpm in the assessment of both periods before and after 32 weeks of gestational age, suggesting the influence of the maturation of the fetal autonomic nervous system with pregnancy progression.
authors.affiliation: Medicine Faculty, University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Ana Luisa Fernandes
authors.initials: AL
authors.lastname: Lauletta
authors.affiliation: Division of Obstetrics, Department of Obstetrics and Gynecology, School of Medicine, University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Roseli Mieko Yamamoto
authors.initials: RM
authors.lastname: Nomura
authors.affiliation: Division of Obstetrics, Department of Obstetrics and Gynecology, School of Medicine, University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Seizo
authors.initials: S
authors.lastname: Miyadahira
authors.affiliation: Division of Obstetrics, Department of Obstetrics and Gynecology, School of Medicine, University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Rossana Pulcineli Vieira
authors.initials: RP
authors.lastname: Francisco
authors.affiliation: Division of Obstetrics, Department of Obstetrics and Gynecology, School of Medicine, University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Marcelo
authors.initials: M
authors.lastname: Zugaib
mesh_terms: D000293:Adolescent; D000328:Adult; D015148:Cardiotocography / Q000295:instrumentation*; D005260:Female; D005324:Fetal Movement / Q000502:physiology*; D005865:Gestational Age; D006340:Heart Rate, Fetal / Q000502:physiology*; D006801:Humans; D011247:Pregnancy; D011263:Pregnancy Trimester, Third; D011446:Prospective Studies; D055815:Young Adult