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Introduction: Noninvasive fetal heart rate monitoring using transabdominal fetal electrocardiographic detection is now commercially available and has been demonstrated to be an effective alternative to traditional Doppler ultrasonographic techniques. Our objective in this study was to compare the results of computerized identification of fetal heart rate patterns generated by ultrasound-based and transabdominal fetal electrocardiogram-based techniques with simultaneously obtained fetal scalp electrode-derived heart rate information.Material and Methods: We applied an objective computer-based analysis for recognition of fetal heart rate patterns (Monica Decision Support) to data obtained simultaneously from a direct fetal scalp electrode, Doppler ultrasound, and the abdominal-fetal electrocardiogram techniques. This allowed us to compare over 145 hours of fetal heart rate patterns generated by the external devices with those derived from the scalp electrode in 30 term singleton uncomplicated pregnancies during labor. The direct fetal scalp electrode is considered to be the most accurate and reliable technique used in current clinical practice, and was, therefore, used as the standard for comparison. The program quantified the baseline heart rate, long- and short-term variability. It indicated when an acceleration or deceleration was present and whether it was large or small.Results: Ultrasound was associated with significantly greater deviations from the fetal scalp electrode results than the abdominal fetal electrocardiogram technique in recognizing the correct baseline heart rate, its variability, and the presence of small and large accelerations and small decelerations. For large decelerations the two external methods were each not significantly different from the scalp electrode results.Conclusions: Noninvasive fetal heart rate monitoring using maternal abdominal wall electrodes to detect fetal cardiac activity more reliably reproduced the computerized analysis of heart rate patterns derived from a direct fetal scalp electrode than did traditional ultrasound-based monitoring. Abdominal-fetal electrocardiogram should, therefore, be considered a primary option for externally monitored patients. [ABSTRACT FROM AUTHOR]

This article discusses the new labor evaluation guidelines issued by the American College of Obstetricians and Gynecologists and the Society for Maternal & Fetal Medicine. Topics covered include the character of birthing practice, the rising cesarean rate in the U.S., and the diagnosis of dystocia and its effect on the cesarean rate. Explained also are abnormal labor progress, misconceptions about the Friedman system of labor assessment and management and the diagnosis of arrest of dilatation.

The assessment of uterine contractions is important in clinical decision-making, but the precise role for appraising contractions remains controversial. Four clinical approaches to assessing contractions are available: manual palpation; intrauterine pressure determination; external tocodynamometry; and electrohysterography. Palpation is inexpensive and harmless but requires the constant bedside presence of a trained observer. Intrauterine pressure measurement is considered the most sensitive and specific technique, and has become the standard by which other methods are judged; however, its quantitative measurements are not always precise or reproducible. Moreover, the availability of intrauterine pressure measurements does not seem to improve maternal or neonatal outcomes in most situations. External tocodynamometry is the most widely used technique. It is easy to apply and provides reasonably accurate information about the frequency and duration of contractions, but not their amplitude. It can require frequent adjustment during labor and might not work well in patients who are obese. Electrohysterography is a recently available noninvasive technology that detects uterine electrical activity using electrodes placed on the mother's abdominal wall. This approach is at least as reliable and accurate as tocodynamometry. [ABSTRACT FROM AUTHOR]

Objective To evaluate the performance of external electronic fetal heart rate and uterine contraction monitoring according to maternal body mass index. Design Secondary analysis of prospective equivalence study. Setting Three US urban teaching hospitals. Sample Seventy-four parturients with a normal term pregnancy. Methods The parent study assessed performance of two methods of external fetal heart rate monitoring (abdominal fetal electrocardiogram and Doppler ultrasound) and of uterine contraction monitoring (electrohystero-graphy and tocodynamometry) compared with internal monitoring with fetal scalp electrode and intrauterine pressure transducer. Reliability of external techniques was assessed by the success rate and positive percent agreement with internal methods. Bland-Altman analysis determined accuracy. We analyzed data from that study according to maternal body mass index. Main outcome measures We assessed the relationship between body mass index and monitor performance with linear regression, using body mass index as the independent variable and measures of reliability and accuracy as dependent variables. Results There was no significant association between maternal body mass index and any measure of reliability or accuracy for abdominal fetal electrocardiogram. By contrast, the overall positive percent agreement for Doppler ultrasound declined ( p = 0.042), and the root mean square error from the Bland-Altman analysis increased in the first stage ( p = 0.029) with increasing body mass index. Uterine contraction recordings from electrohysterography and tocodynamometry showed no significant deterioration related to maternal body mass index. Conclusions Accuracy and reliability of fetal heart rate monitoring using abdominal fetal electrocardiogram was unaffected by maternal obesity, whereas performance of ultrasound degraded directly with maternal size. Both electrohysterography and tocodynamometry were unperturbed by obesity. [ABSTRACT FROM AUTHOR]

Objective. Compare the accuracy and reliability of fetal heart rate identification from maternal abdominal fetal electrocardiogram signals (ECG) and Doppler ultrasound with a fetal scalp electrode. Design. Prospective open method equivalence study. Setting. Three urban teaching hospitals in the Northeast United States. Sample. 75 women with normal pregnancies in labor at >37 weeks of gestation. Methods. Three fetal heart rate detection methods were used simultaneously in 75 parturients. The fetal scalp electrode was the standard against which abdominal fetal ECG and ultrasound were judged. Main outcome measures. The positive percent agreement with the fetal scalp electrode indicated reliability. Bland-Altman analysis determined accuracy. The confusion rate indicated how frequently the devices tracked the maternal heart rate. Results. Positive percent agreement was 81.7 and 73% for the abdominal fetal ECG and ultrasound, respectively ( p = 0.002). The abdominal fetal ECG had a lower root mean square error than ultrasound (5.2 vs. 10.6 bpm, p < 0.001). The confusion rate for ultrasound was 20-fold higher than for abdominal ECG (8.9 vs. 0.4%, respectively, p < 0.001). Conclusion. Compared with the fetal scalp electrode, fetal heart rate detection using abdominal fetal ECG was more reliable and accurate than ultrasound, and abdominal fetal ECG was less likely than ultrasound to display the maternal heart rate in place of the fetal heart rate. [ABSTRACT FROM AUTHOR]

A response from the author of the article "Accuracy and reliability of fetal heart rate monitoring using maternal abdominal surface electrodes" in the November 2012 issue is presented.