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During labor mother and fetus are evaluated at intervals to assess their well-being and determine how the labor is progressing. These assessments require skillful physical diagnosis and the ability to translate the acquired information into meaningful prognostic decision-making. We describe a coordinated approach to the assessment of labor. Graphing of serial measurements of cervical dilatation and fetal station creates "labor curves," which provide diagnostic and prognostic information. Based on these curves we recognize nine discrete labor abnormalities. Many may be related to insufficient or disordered contractile mechanisms. Several factors are strongly associated with development of labor disorders, including cephalopelvic disproportion, excess analgesia, fetal malpositions, intrauterine infection, and maternal obesity. Clinical cephalopelvimetry involves assessing pelvic traits and predicting their effects on labor. These observations must be integrated with information derived from the labor curves. Exogenous oxytocin is widely used. It has a high therapeutic index, but is easily misused. Oxytocin treatment should be restricted to situations in which its potential benefits clearly outweigh its risks. This requires there be a documented labor dysfunction or a legitimate medical reason to shorten the labor. Normal labor and delivery pose little risk to a healthy fetus; but dysfunctional labors, especially if stimulated excessively by oxytocin or terminated by complex operative vaginal delivery, have the potential for considerable harm. Conscientiously implemented, the approach to the evaluation of labor outlined in this review will result in a reasonable cesarean rate and minimize risks that may accrue from the labor and delivery process., (© 2020 Walter de Gruyter GmbH, Berlin/Boston.)

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., (© 2019 The Authors. Acta Obstetricia et Gynecologica Scandinavica published by John Wiley & Sons Ltd on behalf of Nordic Federation of Societies of Obstetrics and Gynecology (NFOG).)

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., (© 2014 Nordic Federation of Societies of Obstetrics and Gynecology.)

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., (© 2012 The Authors Acta Obstetricia et Gynecologica Scandinavica© 2012 Nordic Federation of Societies of Obstetrics and Gynecology.)

Despite almost universal fetal monitoring during labor, debates over its role and benefits persist in the medical community and in obstetric negligence lawsuits. Irrespective, there is widespread agreement that improvement in perinatal outcome is possible and that the events of labor contribute significantly to perinatal hazards. Timely application and proper interpretation of the fetal heart rate pattern in concert with evaluations of the maternal condition and the feasibility of safe vaginal delivery permit an evaluation of the quality of care and the preventability of fetal injury whether in peer review or in malpractice cases.

Objective The objective of this study was to compare performance of a maternal surface electrode patch with ultrasound- and tocodynamometer-based monitoring to detect fetal heart rate and uterine contractility in late preterm labors. Study Design Thirty women between 34 0/7 and 36 6/7 weeks' gestation were monitored simultaneously with a Doppler/tocodynamometer system and a wireless fetal–maternal abdominal surface electrode system. Fetal and maternal heart rate and uterine contraction data from both systems were compared. Reliability was measured by the success rate and percent agreement. Deming regression and Bland–Altman analysis estimated the concordance between the systems. Uterine contractions were assessed by visual interpretation of monitor tracings. Results The success rate for the surface electrode system was 89.5% (95% confidence interval [CI], 85.7–93.3), and for ultrasound it was 88.4% (95% CI, 84.9–91.9; p = 0.73), with a percent agreement of 88.1% (95% CI, 84.2–92.8). Results were uninfluenced by the patients' body mass. The mean Deming slope was 1 and the y-intercept was −3.0 beats per minute (bpm). Bland–Altman plots also showed a close relationship between the methods, with limits of agreement less than 10 bpm. The percent agreement for maternal heart rate was 98.2% (95% CI, 97.4–98.8), and for uterine contraction detection it was 89.5% (95% CI, 85.5–93.4). Conclusion Fetal heart rate and uterine contraction monitoring at 34 0/7 to 36 6/7 weeks using abdominal surface electrodes was not inferior to Doppler ultrasound/tocodynamometry for fetal–maternal assessment. Registration clinicaltrials.gov/February 20, 2017/identifier NCT03057275. Key Points Monitoring the preterm fetal heart rate with surface electrodes is feasible. Preterm contractions can be monitored with surface electrodes. The technique was noninferior to standard external monitors. [ABSTRACT FROM AUTHOR]