Fetal Heart Rate Accelerations Research Articles

Comparação dos padrões da frequência cardíaca fetal no segundo e terceiro trimestres da gestação

to compare the patterns of fetal heart rate (FHR) in the second and third trimesters of pregnancy. a prospective and comparative study performed between January 2008 and July 2009. The inclusion criteria were: singleton pregnancy, live fetus, pregnant women without clinical or obstetrical complications, no fetal malformation, gestational age between 24 and 27 weeks (2nd trimester - 2T) or between 36 and 40 weeks (3rd trimester - 3T). Computerized cardiotocography (System 8002 - Sonicaid) was performed for 30 minutes and the fetal biophysical profile was obtained. System 8002 analyzes the FHR tracings for periods of 3.75 seconds (1/16 minutes). During each period, the mean duration of the time intervals between successive fetal heart beats is determined in milliseconds (ms); the mean FHR and also the differences between adjacent periods are calculated for each period. The parameters included: basal FHR, FHR accelerations, duration of high variation episodes, duration of low variation episodes and short-term variation. The dataset was analyzed by the Student t test, chi-square test and Fisher's exact test. Statistical significance was set at p<0.05. eighteen pregnancies on the second trimester were compared to 25 pregnancies on the third trimester. There was a significant difference in the FHR parameters evaluated by computerized cardiotocography between the 2T and 3T groups, regarding the following results: mean basal FHR (mean, 143.8 bpm versus 134.0 bpm, p=0.009), mean number of transitory FHR accelerations > 10 bpm (3.7 bpm versus 8.4 bpm, p <0.001) and >15 bpm (mean, 0.9 bpm versus 5.4 bpm, p <0.001), mean duration of high variation episodes (8.4 min versus 15.4 min, p=0.008) and mean short - term variation (8.0 ms versus 10.9 ms, p=0.01). The fetal biophysical profile showed normal results in all pregnancies. the present study shows significant differences in the FHR characteristics when the 2nd and 3rd trimesters of pregnancy are compared and confirms the influence of autonomic nervous system maturation on FHR regulation.

La frecuencia cardiaca en fetos con restricción en el crecimiento y desarrollo

Fetal heart rate (FHR) values and accelerations were determined in fetuses with restricted growth and development and were compared with those in a control group. The study design was open, prospective, comparative and exploratory. The sample consisted of 40 patients divided into two groups. Group 1 (problem group) was composed of 20 pregnant women diagnosed with restricted fetal growth and development. Group 2 (control group) consisted of 20 patients with normal pregnancies. Ultrasound was used to determine the biparietal diameter of the fetuses. FHR and uterine contractility were measured. The Apgar test was used to evaluate neonatal status. Neonates were weighed and measured. Basal FHR in group 1 was 5 beats higher with an amplitude of 3 beats less than in the control group. These differences were highly significant. Dispersion diagrams were drawn and linear regression was calculated for the parietal diameters of fetuses with restricted growth. The equation was y=0.547 x+64.38 and the correlation coefficient was R 2=0.3561. In the control group the equation for the linear regression was y=2.0344 x+12.944 and the correlation coefficient was R 2=0.9981. The means of the biparietal diameters of groups 1 and 2 were compared but no significant differences were found. The mean values for uterine height and abdominal perimeter for the two groups were 33.45 cm and 101.15 cm, respectively. The physical status of the newborns was evaluated using the Apgar test. At 1 min, two neonates were depressed with an Apgar score of 6. Twelve neonates were vigorous with scores ranging from 7 to 9 and the six remaining neonates were not tested. At 5 min, scores ranged from 7 to 9. When the two groups of neonates were compared, the weights and heights of those in group 1 were 243 g and 2 cm lower and these differences were significant ( p<0.05).

Difference of fetal heart rate accelerations based on 10 and 15 beats per minute

To evaluate the correlation of 10 b.p.m.-10 s and 15 b.p.m.-15 s fetal heart rate (FHR) accelerations in gestations before or after 32 weeks using computerized analysis. A combination of amplitude and duration of FHR accelerations, 10 b.p.m.-10 s (Acc10-10) and 15 b.p.m.-15 s (Acc15-15), was analyzed according to gestational weeks between January 1999 and December 2005 in 2358 normal pregnant women who received a non-stress test at 30-42 gestational weeks. A linear regression model between Acc10-10 and Acc15-15 was estimated, and the duration difference between 10 b.p.m. and 15 b.p.m. was converted into seconds. Before 32 weeks of gestation, the mean number of FHR accelerations based on 15 b.p.m. was below 2.00 (mean + or - standard error, 1.58 + or - 0.19). The correlation between Acc10-10 and Acc15-15 was Acc15-15 + 2.8 = Acc10-10 (r(2) = 0.94, P = 0.0013). The mean duration difference between 10 b.p.m. and 15 b.p.m. was 36.8 s (range, 4-227 s). Our study verified the difference of Acc10-10 and Acc15-15 using computerized analysis as the base of visual interpretation of the definition of FHR acceleration. Acc15-15 did not occur often enough to be relevant to the definition of FHR acceleration before 32 weeks' gestation. The difference between the mean number of FHR accelerations based on 10 b.p.m. and 15 b.p.m. within a 20-min window was 2.8.

Detecting gross fetal movements using fetal magnetocardiography

Event Abstract Back to Event Detecting gross fetal movements using fetal magnetocardiography Peter V. Leeuwen1*, Daniel Geue2, Silke Lange1 and Dietrich H. Grönemeyer1 1 University of Witten / Herdecke, Dept. of Radiology / Microtherapy, Germany 2 VISUS Technology Transfer, Department of Psychology, Faculty of Arts and Sciences, Germany Fetal development is associated with the emergence of fetal movements (FM). Gross FM involve the limbs and/or the trunk and are accompanied by changes in heart rate and heart rate variability (HRV). To detect such FM, we developed a semi-automatic technique which analyzes changes in signal morphology of multichannel fetal magnetocardiogram (FMCG) signals over time. The technique exploits the changes QRS signal shape and amplitude in specific channels resulting from gross FM. From our database of FMCG records, we selected 26 five-minute FMCGs in 14 healthy pregnant women (31st-41st week of gestation) in which FM were suspected on the basis of fetal heart rate accelerations. In each recording, after the removal of the maternal artifact, the fetal QRS complexes were identified using template matching. In each channel, the minimum and maximum amplitudes of each QRS complex were determined. In the actogram, the beat-to-beat changes in maximum and minimum values, respectively, were quantified using the variance over a 20 beat window. Automatically determined, rapid increases in variance were considered reflecting changes in fetal position. The timings of these increases were examined together with changes in fetal heart rate (determined by the RR intervals derived from the QRS complexes). We found between 1-4 episodes of rapid increases in variance in each of the 26 actograms. These episodes were associated with an immediate decrease of 31.7±18.8 ms from overall RR interval (heart rate increase: 11.3±6.5 bpm). Beat-to-beat RR interval variability was reduced from overall 7.4±3.2 ms to 3.8±1.7 ms immediately following the begin of the actographically determined episodes. The results suggest that the majority of the episodes reflected FM and that this actographic approach may be used to automatically scan FMCG recordings for such movement. This will be helpful in categorizing FMCG recordings with respect to fetal behavioral state and improve the assessment of fetal HRV. Conference: Biomag 2010 - 17th International Conference on Biomagnetism , Dubrovnik, Croatia, 28 Mar - 1 Apr, 2010. Presentation Type: Poster Presentation Topic: Fetal and neonatal biomagnetism Citation: Leeuwen PV, Geue D, Lange S and Grönemeyer DH (2010). Detecting gross fetal movements using fetal magnetocardiography. Front. Neurosci. Conference Abstract: Biomag 2010 - 17th International Conference on Biomagnetism . doi: 10.3389/conf.fnins.2010.06.00098 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 23 Mar 2010; Published Online: 23 Mar 2010. * Correspondence: Peter V Leeuwen, University of Witten / Herdecke, Dept. of Radiology / Microtherapy, Herdecke, Germany, sci@van-leeuwen.de Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Peter V Leeuwen Daniel Geue Silke Lange Dietrich H Grönemeyer Google Peter V Leeuwen Daniel Geue Silke Lange Dietrich H Grönemeyer Google Scholar Peter V Leeuwen Daniel Geue Silke Lange Dietrich H Grönemeyer PubMed Peter V Leeuwen Daniel Geue Silke Lange Dietrich H Grönemeyer Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Efeitos da anemia materna na cardiotocografia computadorizada e perfil biofísico fetal

To evaluate the influence of maternal hemoglobin (Hb) levels in the patterns of fetal heart rate (FHR) and in the fetal biophysical profile (FBP) in term gestations. Pregnant women with anemia (Hb<11.0 g/dL) were prospectively evaluated between the 36(th) and the 40(th) week of gestation, from January 2008 to March 2009. The Control Group was composed of term and healthy pregnant women, with normal values of hemoglobin (Hb>11,0 g/dL). Cases of anomalies or fetal growing restrictions were excluded. The FHR evaluation was performed by computerized cardiotocography (8002 System-Sonicaid), and by record analysis during 30 minutes of exam. The FBP was done in all the patients. Student's, chi2 and Fisher's exact tests were used, with 0.05 significance level. The average of maternal Hb in the group with anemia (n=18) was 9.4 g/dL (DP=1.4 g/dL), and in the control group, 12.4 g/dL (DP=1.3 g/dL). There has been no significant mean differences between groups concerning the cardiotocography parameters, respectively: basal FHR(131.3 versus 133.7 bpm, p=0.5), FHR accelerations > 10b pm (7.9 versus 8.2, p=0.866), FHR accelerations > 15 bpm (5.2 versus. 5.4, p=0.9), episodes of high variation of the FHR (17.1 versus 15.5 min, p=0.5), episodes of variation of the FHR (4.4 versus 3.6 min, p=06), and short term variation (10.5 versus 10.9 ms, p=0.5). In both groups, all patients presented normal FBP. This study suggests that light or moderate maternal anemia, without other maternal or fetal comorbidity, is not associated with abnormalities in the parameters of fetal biophysical profile and of the FHR analyzed by computerized cardiotocography.

Sleep–wake cycles in normal fetuses

To study the normal ranges of sleep-wake cycles in normal fetuses. A total of 600 fetal heart rate (FHR) tracings were studied from uncomplicated singleton pregnancies at a gestational age between 30 and 40 weeks with a 1-h recording. Two obstetricians interpreted all the FHR recordings independently. The mean baseline FHR was 141.6 (7.6) beats/min. The median relative percentage time spent in a quiet state was 26% (0-88.6). The median duration of time spent in a quiet state was 15.7 min (0-53.2) within a 1-h recording. Both quiet and active states were established in 84% of cases. The number of FHR accelerations per hour in an active state increased with advancing gestational age, whereas the baseline FHR gradually decreased. Normal ranges of fetal sleep-wake cycles were established. Fetuses between 30 and 40 weeks had wide variations in the percentage of time spent in sleep-wake states.

Heart Rate Variability Analysis Allows Early Asphyxia Detection in Ovine Fetus

Fetal heart rate (FHR) monitoring is commonly used to predict asphyxia but clinical and experimental studies have questioned its diagnostic value. We examined the usefulness of fetal heart rate variability (fHRV) measures in detecting early asphyxia using chronically instrumented fetal sheep under normoxic (n = 6) and asphyxic conditions (3 umbilical cord occlusions, n = 6). The occlusions consistently led to pH decreases from 7.35 +/- 0.01 to 7.09 +/- 0.03 ( P < .05). FHR showed biphasic deceleration during each occlusion, associated with increasing arterial blood pressure ( P < .05). RMSSD, an index of vagal modulation of fHRV, increased consistently during repeated occlusion induced FHR decelerations ( P < .05). Under normoxic conditions, RMSSD did not change during FHR decelerations and decreased during FHR accelerations ( P < .05). Our results suggest that an increase of RMSSD in association with FHR decelerations reflects initial vagal activation during fetal asphyxia. RMSSD may accurately identify asphyxic fetuses early. Clinical validation is needed.

Detailed multigrade evaluation of fetal disorders with the quantified actocardiogram

To evaluate fetal disorders using detailed quantitative values from the actocardiogram (ACG) involving simultaneous tracing of ultrasonic Doppler fetal movement bursts and fetal heart rate (FHR). Duration of FHR accelerations and fetal movement bursts were measured manually in 20 common fetal disorders. The severity of the fetal disorder was estimated using the FHR acceleration duration to movement burst ratio (A/B ratio) and 10-0 clinical severity ranks derived from the A/B ratio. The correlation of the A/B ratio and 1 and 5 min Apgar scores, as well as numerically expressed long-term outcomes were studied. A/B ratios were significantly correlated with the 1 and 5 min Apgar scores and the numerically evaluated long-term outcomes. Controversial cases of FHR pattern were more easily understood using the A/B ratio. The 10-0 severity derived from the A/B ratio was useful in clinical fetal studies. Common fetal disorders were evaluated quantitatively and in more detail using the A/B ratio from the actocardiogram than when using common binary good or bad evaluation. The A/B ratio was useful in outcome estimation, where the prognostic capability of the A/B ratio was confirmed by significant correlation with 1 and 5 min Apgar scores and long-term outcomes of fetal disorders.

Fetal Heart Rate Accelerations and the Risk of Cerebral Lesions and Poor Neurodevelopmental Outcome in Very Low Birthweight Neonates

Fetal Heart Rate Accelerations and the Risk of Cerebral Lesions and Poor Neurodevelopmental Outcome in Very Low Birthweight Neonates

Fetal Heart Rate Accelerations and the Risk of Cerebral Lesions and Poor Neurodevelopmental Outcome in Very Low Birthweight Neonates

The risk of intraventricular hemorrhage and periventricular leukomalacia correlates with fetal brain immaturity. Given that the appearance of fetal heart rate (FHR) accelerations is associated with brain maturation, we tested the hypothesis that neonatal cerebral lesions and developmental delay in very low birthweight newborns are associated with absent reactivity of the FHR tracing prior to delivery. We analyzed the FHR tracing of 97 fetuses with birthweight < 1200 g who underwent head ultrasound at day 3 and Bayley Scales of Infant Development testing at age 1 year. We used multivariate analysis to adjust for confounding variables. We found that the absence of two FHR accelerations of 10 beats per minute (bpm) for 10 seconds twice in a 20-minute window 1 hour before delivery was associated with intraventricular hemorrhage and/or periventricular leukomalacia ( P < 0.01) and a significant risk for mental and psychomotor delays by Bayley testing ( P < 0.001). The absence of accelerations of 15 bpm for 15 seconds was not associated with these abnormalities. The absence of FHR accelerations before delivery suggests a greater risk for cerebral injury and developmental delay in the very premature neonate.

Postural effects when cycling in late pregnancy

This study assessed if upright cycling is preferable to semi-recumbent cycling during pregnancy. Healthy women with low risk singleton pregnancies were tested at 34-38 weeks gestation. They cycled for 12 min, either semi-recumbent (45 degrees, n = 27) or upright (n = 23), at 135-145 beats min(-1). When semi-recumbent, minute ventilation was greater (p<0.03) at rest and systolic blood pressure and pulse pressure were greater during exercise (p<0.05). Exercise maternal heart rate, oxygen consumption, oxygen consumption per kilogram, minute ventilation, cardiac output, stroke volume, mean and diastolic blood pressures and arterio-venous oxygen difference were posture-independent. All increased with exercise (p<0.01), except stroke volume when semi-recumbent (p>0.05). Small post-exercise fetal heart rate increases (by 8 beats min(-1), p<0.05) were similar in both postures (n = 11 in each sub-group), with no adverse changes. Fetal heart rate accelerations and uterine activity (n = 11 in each sub-group) were not influenced by posture or exercise. (1) Neither posture had a distinct advantage. (2) Both postures were safe for short duration cycling. (3) The same target maternal heart rates are suitable for both postures because they resulted in similar oxygen consumptions and fetal heart rates.

The Fidgety Fetus Hypothesis

Postprandial hyperglycemia appears to increase the risk of macrosomia, but it is not clear why a majority of fetuses are unaffected. One possibility, the “fidgety fetus hypothesis,” posits that fetal activity is an intrinsic trait that influences birth weight. This study was an attempt to learn whether some infants whose mothers have gestational diabetes mellitus (GDM) may be more active in utero and able to compensate for hyperglycemia, thereby minimizing their risk of macrosomia. Initially, 10 women with diabetes counted kicks twice a day for 30 minutes, and also monitored their blood glucose before and 1 hour after each meal. In a second phase, 13 women with GDM used a home fetal monitoring device (the Card Guard-900P), making it possible to monitor fetal heart rate (FHR) accelerations telemetrically. Finally, fetal monitoring strips from 46 women with GDM were analyzed retrospectively. An active fetus was taken to be one having 4 or more FHR accelerations in a 20-minute period. In no phase of the study were there significant differences between the active and inactive groups in the time that GDM was diagnosed, the time insulin treatment began, or glycosylated hemoglobin levels. In the first phase of the study, there was little variation in fetal movements during an average follow up of 8.5 weeks. Maternal postprandial glucose levels correlated positively with increased birth weight. In the second phase, active fetuses were always active and inactive fetuses always were inactive. Average birth weight percentile, corrected for gestational age, was 37% in the active group and 63% in the inactive group (P = .05). In the final phase, the fetal monitoring strips demonstrated an inverse correlation between the number of FHR accelerations and birth weight corrected for gestational age. Average birth weight percentiles in the active and inactive groups were 37% and 62%, respectively. Macrosomic fetuses were found only in the inactive group. These findings support the “fidgety fetus” hypothesis that increased fetal activity may minimize the effect of hyperglycemia on subsequent birth weight. Inactive fetuses are at increased risk of glucose-mediated macrosomia, making it especially important to treat hyperglycemia and maintain close surveillance in these cases.

The computerized fetal heart rate analysis in post-term pregnancy identifies patients at risk for fetal distress in labour

Objective To ascertain the diagnostic ability of a computerized fetal heart rate (FHR) analysis system in the identification of patients at risk of fetal distress in labour. Study design Three hundred and two healthy post-term pregnancies were enrolled in a retrospective, cross-sectional study and subdivided into two groups, with ( n = 42) or without ( n = 260) fetal distress in labour. The last computerized FHR recording before onset of labour was analyzed. Results The two groups showed a significant difference only in FHR baseline and in percentage of small accelerations on total. The multivariate analysis showed that only the percentage of small accelerations was significantly related to the labour outcome. A higher diagnostic accuracy was obtained with use of neural network analysis, which allowed a sensitivity of 56%, specificity 91%, positive predictive value 53% and negative predictive value 92% with an overall accuracy of 86%. Conclusions The increase in FHR baseline and in small FHR accelerations can be major factors in the prediction of subsequent fetal distress in healthy term fetuses. Use of neural networks seems to further improve the ability of computerized FHR analysis in the prediction of intrapartum distress.

Effect of Chronic Maternal Methadone Therapy on Intrapartum Fetal Heart Rate Patterns

Treatment of maternal opioid dependence with methadone is associated with a delay in fetal heart rate (FHR) accelerations in nonstress tests. The objective of this investigation was to determine the effect of methadone maintenance therapy on intrapartum FHR patterns. This retrospective cohort study compared intrapartum FHR tracings from 56 methadone-treated patients > or =36 weeks gestation with a control group of nonsubstance using patients matched for maternal age, parity, gestational age, and ethnicity. Blinded FHR interpretation included the recording of baseline, variability, accelerations, and late or severe variable decelerations. The 8-point FHR scoring system was based on the National Institute of Child Health and Human Development Research Planning Workshop guidelines. We considered a 25% reduction in the score during the latent phase to be significant. The median maintenance dose of methadone was 70 mg daily, with a range between 20 mg and 130 mg. Each patient tested negative for other substances on urine screening before admission. The significantly lower FHR score in the methadone group (mean difference, 1.4; 95% confidence interval, 1.1 to 1.7) was attributed to a lower baseline (P <.05), less moderate or marked variability (P <.01), and a lower proportion of accelerations during the first stage of labor (P <.01). A higher proportion of methadone-exposed fetuses had late or severe variable decelerations in the second stage (44.2% vs 22.9%; P <.03). Analgesic needs, operative vaginal or cesarean delivery rates, and Apgar scores less than 7 at 1 and 5 minutes were not significantly different between the two groups. Chronic maternal methadone treatment affects intrapartum FHR patterns by reducing the variability, baseline, and proportion of accelerations during the first stage. These subtle drug-induced effects do not compromise intrapartum decision-making or immediate newborn adjustments.

Cross-over trial of fetal heart rate response to halogen light and vibroacoustic stimulation

Objective. The purpose of this study was to compare the effect of halogen light and vibroacoustic stimulation on fetal heart rate (FHR) responsiveness and on nonstress test (NST) results.Methods. Sixty consecutively-chosen patients between 33 and 39 weeks of gestation underwent an NST on at least three weekly occasions. Each received halogen light (Vector Compact Sport Spot, Ft Lauderdale, FL, USA), vibroacoustic (SolaTone Artificial Larynx, Temecula, CA, USA), and no stimulation in a randomized order. The transabdominal light or vibroacoustic stimulation lasted for 10 seconds. If no initial FHR acceleration occurred, then the stimulus was repeated 10 minutes later up to a maximum of three times. The investigators who interpreted the FHR patterns were blinded as to the type of stimulus used.Results. Reactive results were present in 171 tests (vibroacoustic: 98.3%; light: 96.6%; none: 93.3%). Compared with no stimulation, the mean difference in time from the onset of recorded ‘stimulation’ to the first FHR acceleration was shorter (p < 0.01) with either light (2.7 minutes, 95% confidence interval (CI) 0.9–4.5 minutes) or vibroacoustic stimulation (2.6 minutes, 95% CI 0.8–4.4 minutes). The mean time difference until a reactive result was also shorter (p < 0.05) with either light (2.7 minutes, 95% CI 0.1–4.9 minutes) or vibroacoustic stimulation (2.4 minutes, 95% CI 0.1–4.7 minutes) than with no stimulation. The need for repeated stimulation during each test was infrequent (light: 5.0%; vibroacoustic: 3.3%). No adverse effect from external stimulation was noted on the FHR tracing.Conclusion. Halogen light stimulation is an acceptable alternative to vibroacoustic stimulation in provoking a more rapid fetal heart rate response and in shortening the time before a reactive nonstress test result.

Fetal behavior analyzed by ultrasonic actocardiogram in cases with central nervous system lesions

This study examined whether analysis of fetal behavioral states by monitoring fetal heart rate and movement using an actocardiogram (ACG), could provide prognostic information related to fetal central nervous system (CNS) lesions. The ACG simultaneously records fetal heart rate (FHR) and fetal movement bursts composed of spikes of ultrasonic Doppler signals. Durations of FHR accelerations and fetal movement bursts were measured manually. Five actocardiographic indices were studied in 12 fetuses with CNS lesions and in 14 normal pregnancies of 28-38 weeks. Severity of the fetal CNS lesions was estimated from the acceleration/burst (A/B) duration ratio, which correlated with the rank of the sonographic fetal functional test in cases with CNS lesions. Severity of a fetal lesion may also be estimated by the regression equation of the A/B duration ratio and behavioral ranking. The severity of fetal CNS lesions may be estimated by quantitative analysis of ACG usings the measurement of A/B duration ratio to provide a prognosis. An ACG may demonstrate a loss of CNS control in cases with severe brain damage.

The Fidgety Fetus Hypothesis: Fetal activity is an additional variable in determining birth weight of offspring of women with diabetes

To determine whether some offspring of women with diabetes are intrinsically more active than others in utero and whether those who are active are able to normalize their birth weight despite maternal hyperglycemia. We conducted a three-phase study to view the relationship between fetal movements and subsequent birth weight in women with diabetes. Phase I was designed to assess maternal perception of fetal movements in a population of 10 women with diabetes. To improve our fetal monitoring techniques, in phase II we analyzed fetal movements using the Card Guard home fetal monitoring device (CG 900P) in a population of 13 women with gestational diabetes mellitus (GDM). To apply our observations of fetal movements to a larger population, during phase III we conducted a retrospective analysis of fetal monitoring strips (HP 8041A) from 46 women with GDM to examine the relationship between fetal heart rate (FHR) accelerations and percentile birth weight, corrected for gestational age. Phase I confirmed that there is little variability in fetal movements (i.e., fetal kicks did not significantly deviate from one another on a day-to-day basis). In phase II, the fetal monitoring strips illustrated that the active fetuses (defined as > or = 4 FHR accelerations in a 20-min period) were always active, and the inactive fetuses were always inactive. The mean birth weight percentile, corrected for gestational age, in the active group was 37 vs. 63% in the inactive group (P = 0.05). In phase III, the fetal monitoring strips showed an inverse correlation between the mean number of FHR accelerations and the birth weight of the fetus, corrected for gestational age. The mean birth weight percentile in the active group was 37 vs. 62% in the inactive group (P = 0.0017). The fetus appears to play a role in determining its own destiny. Increased fetal activity may minimize the impact of hyperglycemia on subsequent birth weight. The inactive fetus appears to be at a higher risk for glucose-mediated macrosomia.

The Fidgety Fetus Hypothesis

OBJECTIVE—To determine whether some offspring of women with diabetes are intrinsically more active than others in utero and whether those who are active are able to normalize their birth weight despite maternal hyperglycemia. RESEARCH DESIGN AND METHODS—We conducted a three-phase study to view the relationship between fetal movements and subsequent birth weight in women with diabetes. Phase I was designed to assess maternal perception of fetal movements in a population of 10 women with diabetes. To improve our fetal monitoring techniques, in phase II we analyzed fetal movements using the Card Guard home fetal monitoring device (CG 900P) in a population of 13 women with gestational diabetes mellitus (GDM). To apply our observations of fetal movements to a larger population, during phase III we conducted a retrospective analysis of fetal monitoring strips (HP 8041A) from 46 women with GDM to examine the relationship between fetal heart rate (FHR) accelerations and percentile birth weight, corrected for gestational age. RESULTS—Phase I confirmed that there is little variability in fetal movements (i.e., fetal kicks did not significantly deviate from one another on a day-to-day basis). In phase II, the fetal monitoring strips illustrated that the active fetuses (defined as ≥4 FHR accelerations in a 20-min period) were always active, and the inactive fetuses were always inactive. The mean birth weight percentile, corrected for gestational age, in the active group was 37 vs. 63% in the inactive group (P = 0.05). In phase III, the fetal monitoring strips showed an inverse correlation between the mean number of FHR accelerations and the birth weight of the fetus, corrected for gestational age. The mean birth weight percentile in the active group was 37 vs. 62% in the inactive group (P = 0.0017). CONCLUSIONS—The fetus appears to play a role in determining its own destiny. Increased fetal activity may minimize the impact of hyperglycemia on subsequent birth weight. The inactive fetus appears to be at a higher risk for glucose-mediated macrosomia.

Effect of Betamethasone Administration on Fetal Heart Rate Tracing: A Blinded Longitudinal Study

Objective: Computerized fetal heart rate (FHR) analysis revealed that antenatal corticosteroids transiently suppress multiple parameters of fetal well-being, potentially leading to the erroneous diagnosis of fetal distress and to unnecessary iatrogenic delivery of premature infants. Our aim was to determine whether clinicians who visually analyze FHR tracings detect these suppressive effects, thereby potentially affecting their clinical management decisions. Methods: Singleton pregnancies admitted for preterm labor between 26 and 34 weeks’ gestation received two doses of betamethasone, 24 h apart, and were monitored daily between 16:00 and 19:00 h for 5 days. FHR tracings were randomly coded and presented in a non-consecutive order to four clinicians, who were unaware of the time of steroid administration. FHR baseline, FHR variability, number of accelerations and amplitude of maximal FHR acceleration were determined. Variability was scored semiquantitatively based on a modified Hon score. Analysis of variance (ANOVA) with repeated measures was used for primary analysis and followed up with the Wald test of significance. Corrections for multiple comparisons were made and only p < 0.005 considered significant. ANOVA was also used to assess the uniformity of trend in the interpretation by the four examiners for each given day. Results: Baseline FHR was elevated, FHR variability was decreased, and the number of accelerations decreased on day 1 (p < 0.0001; p < 0.0001; p < 0.0001) and day 2 (p > 0.0001; p < 0.0001; p < 0.0001) in comparison to day 0. On day 3, the FHR baseline, variability and number of accelerations returned to pre-exposure values (p = NS). The maximal amplitude of FHR accelerations showed a trend towards reduction (p = 0.08). Subgroup analysis by gestational age (group I = 26–30 weeks and group II = 30–34 weeks) showed the same response patterns and significance levels for both groups. Conclusions: Betamethasone causes profound, but transient, suppression of FHR parameters, which can mimic fetal distress. This effect is clinically recognized by visual FHR analysis. Clinicians need to be aware of this phenomenon, in order to avoid unwarranted iatrogenic delivery.

Electrophysiologic patterns of fetal heart rate augmentation with terbutaline in complete AV block

Background: The beta-2 agonist terbutaline (terb) increases fetal heart rate (FHR) in fetuses with complete AV block (CAVB) due to either maternal Sjögren’s antibodies (SSA) or left atrial isomerism (LAI), but the electrophysiologic characteristics of the FHR augmentation have not been evaluated. We hypothesized that, reflecting the differing pathophysiology of LAI and SSA CAVB, the patterns of FHR acceleration in terb treated fetuses would differ between those with LAI and those with SSA.