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). Conclusion: 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.Uniterms: fetal heart rate, cardiotocography, gestational age.

Erroneous Recording of Maternal Heart Rate as Fetal Heart Rate During Second Stage of Labour: Isn’t it Time to Stop this?

“…Accelerations are mediated through the fetal somatic nervous system and recorded as a more than 15 bpm increase from the baseline lasting for more than 15 seconds in term fetuses. In pregnancies less than 32 weeks, the minimum amplitude required for the characterization of the accelerations is 10 bpm [20]. The absence of accelerations is not an abnormal feature in intrapartum FHR traces [21].…”

Analysis of the fetal cardio-electrohysterographic coupling at the third trimester of gestation in healthy women by Bivariate Phase-Rectified Signal Averaging

“…Fetal heart rate (FHR) monitoring by transabdominal recordings can be used to provide noninvasive autonomic markers of fetal wellbeing [7,8]. Changes of FHR depict the influence of the maturation of the fetal autonomic nervous system during pregnancy progression [9]. Signal processing techniques can also provide a reproducible numerical assessment of the relationship between FHR and EHG [10,11].…”

Influencia del ejercicio físico desarrollado durante el embarazo en la respuesta cardiaca fetal = Influence of a physical activity program performed during pregnancy on fetal heart response

“…Clasificación de la FCF en el tercer trimestre de embarazo (Parada et al, 2007). Como se observa en la tabla el rango normal de FCF se sitúa entre 120-160 lat/min siendo la media de la FCF durante el tercer trimestre de 140-145 lat/min (Lauletta et al, 2014;Park et al, 2001;Van Leeuwen et al, 1999).…”

“…La progresiva maduración del SNP provoca el descenso de la FCF a lo largo del embarazo. A su vez la maduración del SNS desencadena en el CF periodos de aceleración de la frecuencia cardiaca (Lauletta et al, 2014;Schneider et al, 2009;Van Leeuwen et al, 1999). Así mismo se ha descubierto que el mayor periodo de maduración del sistema nervioso autónomo se da entre las semanas 25-30 de gestación con un aumento de la variabilidad de la FCF (VFCF) (Wakai, 2004).…”