La frecuencia cardiaca fetal en embarazadas adolescentes

Basal values of fetal heart rate (FHR) and amplitude of the accelerations were determined in pregnant adolescents and compared with those of a control group. The study design was open, prospective, comparative and exploratory. The sample consisted of 40 patients divided into two groups. Group 1 (the problem group) was composed of 20 pregnant adolescents. Group 2 (the control group) consisted of 20 patients with a normal pregnancy. Ultrasound was used to determine the biparietal diameters of the fetuses. FHR and uterine contractility were measured for 2 h. An HP cardiotocograph, model 1350, series 50 XM was used. All these studies were longitudinal. Basal FHR and the amplitude of the accelerations of the two groups were compared. In group 1, FHR was 4 beats higher and this difference was highly significant. Amplitude was 1 beat lower. In two FHR recordings, Type II Dips of moderate and large amplitude were registered during a reactive pattern. A dispersion diagram was drawn and the linear regression of the biparietal diameter values of group 1 fetuses was calculated. The linear regression was y=2.5053x−1.3545. The correlation coefficient was very good (R2=0.9579). In group 2 (normal distribution) the linear regression equation was y=2.0344x+12.944. The correlation coefficient was excellent (R2=0.9981). The means of the biparietal diameters of the two groups were also compared. In group 1 the mean was 9 mm lower but this difference was non-significant. The means of uterine height and abdominal perimeter were 33.95 and 95.95 cm, respectively. The physical status of the newborns was evaluated using the Apgar test at 1 and 5 min. Eleven neonates were not tested. One neonate was born depressed. Eight other neonates showed a score in the range of 7–8. At 5 min, their score was between 8 and 9. The weight and height of the neonates in the two groups were compared. In group 1, weight was 16 g higher and weight was also higher but these differences were non-significant.