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Objective To predict instrumental vaginal delivery or caesarean section for suspected fetal distress or failure to progress.Design Secondary analysis of a randomised trial.Setting Three academic and six non-academic teaching hospitals in the Netherlands.Population 5667 labouring women with a singleton term pregnancy in cephalic presentation.Methods We developed multinomial prediction models to assess the risk of operative delivery using both antepartum (model 1) and antepartum plus intrapartum characteristics (model 2). The models were validated by bootstrapping techniques and adjusted for overfitting. Predictive performance was assessed by calibration and discrimination (area under the receiver operating characteristic), and easy-to-use nomograms were developed.Main outcome measures Incidence of instrumental vaginal delivery or caesarean section for fetal distress or failure to progress with respect to a spontaneous vaginal delivery (reference).Results 375 (6.6%) and 212 (3.6%) women had an instrumental vaginal delivery or caesarean section due to fetal distress, and 433 (7.6%) and 571 (10.1%) due to failure to progress, respectively. Predictors were age, parity, previous caesarean section, diabetes, gestational age, gender, estimated birthweight (model 1) and induction of labour, oxytocin augmentation, intrapartum fever, prolonged rupture of membranes, meconium stained amniotic fluid, epidural anaesthesia, and use of STanalysis (model 2). Both models showed excellent calibration and the receiver operating characteristics areas were 0.70-0.78 and 0.73-0.81, respectively. ConclusionIn Dutch women with a singleton term pregnancy in cephalic presentation, antepartum and intrapartum characteristics can assist in the prediction of the need for an instrumental vaginal delivery or caesarean section for fetal distress or failure to progress.

Objective The objective of this study was to quantify inter-and intra-observer agreement on classification of the intrapartum cardiotocogram (CTG) and decision to intervene following STAN guidelines.Design A prospective, observational study.Setting Obstetrics Department of a tertiary referral hospital.Population STAN recordings of 73 women after 36 weeks of gestation with a high-risk pregnancy, induced or oxytocinaugmented labour, meconium-stained amniotic fluid or epidural analgesia.Methods Six observers classified 73 STAN recordings and decided if and when they would suggest an intervention. Proportions of specific agreement (P s ) and kappa values (K) were calculated.Main outcome measures Agreement upon classification of the intrapartum CTG and decision to perform an intervention.Results Agreement for classification of a normal and a (pre)terminal CTG was good (P s range 0.50-0.84), but poor for the intermediary and abnormal CTG (P s range 0.34-0.56). Agreement on the decision to intervene was higher, especially on the decision to perform 'no intervention' (P s range 0.76-0.94). Overall inter-observer agreement on the decision to intervene was considered moderate in five of six observer combinations according to the kappa (K range 0.42-0.73). Intra-observer agreement for CTG classification and decision to intervene was moderate (K range 0.52-0.67 and 0.61-0.75).Conclusions Inter-observer agreement on classification of the intrapartum CTG is poor, but addition of information regarding fetal electrocardiogram, especially in case of intermediary or abnormal CTG traces, results in a more standardised decision to intervene.Keywords Cardiotocography, fetal electrocardiogram, inter-and intra-observer agreement, ST analysis.Please cite this paper as: Westerhuis M, van Horen E, Kwee A, van der Tweel I, Visser G, Moons K. Inter-and intra-observer agreement of intrapartum ST analysis of the fetal electrocardiogram in women monitored by STAN. BJOG 2009;116:545-551.

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EFM + ST does not reduce the risk of metabolic acidosis, but it does reduce the need for instrumental vaginal deliveries and fetal blood sampling.

Introduction Doppler ultrasound cardiotocography is a non‐invasive alternative that, despite its poor specificity, is often first choice for intrapartum monitoring. Doppler ultrasound suffers from signal loss due to fetal movements and is negatively correlated with maternal body mass index (BMI). Reported accuracy of fetal heart rate monitoring by Doppler ultrasound varies between 10.6 and 14.3 bpm and reliability between 62.4% and 73%. The fetal scalp electrode (FSE) is considered the reference standard for fetal monitoring but can only be applied after membranes have ruptured with sufficient cervical dilatation and is sometimes contra‐indicated. A non‐invasive alternative that overcomes the shortcomings of Doppler ultrasound, providing reliable information on fetal heart rate, could be the answer. Non‐invasive fetal electrocardiography (NI‐fECG) uses a wireless electrode patch on the maternal abdomen to obtain both fetal and maternal heart rate signals as well as an electrohysterogram. We aimed to validate a wireless NI‐fECG device for intrapartum monitoring in term singleton pregnancies, by comparison with the FSE. Material and methods We performed a multicenter cross‐sectional observational study at labor wards of 6 hospitals located in the Netherlands, Belgium, and Spain. Laboring women with a healthy singleton fetus in cephalic presentation and gestational age between 36 and 42 weeks were included. Participants received an abdominal electrode patch and FSE after written informed consent. Accuracy, reliability, and success rate of fetal heart rate readings were determined, using FSE as reference standard. Analysis was performed for the total population and measurement period as well as separated by labor stage and BMI class (≤30 and >30 kg/m2). Results We included a total of 125 women. Simultaneous registrations with NI‐fECG and FSE were available in 103 women. Overall accuracy is −1.46 bpm and overall reliability 86.84%. Overall success rate of the NI‐fECG is around 90% for the total population as well as for both BMI subgroups. Success rate dropped to 63% during second stage of labor, similar results are found when looking at the separate BMI groups. Conclusions Performance measures of the NI‐fECG device are good in the overall group and the separate BMI groups. Compared with Doppler ultrasound performance measures from the literature, NI‐fECG is a more accurate alternative. Especially, when women have a higher BMI, NI‐fECG performs well, resembling FSE performance measures.

Objective To examine detailed intrapartum events in cases of neonatal metabolic acidosis despite monitoring using STAN Ò (cardiotocography [CTG] plus ST waveform analysis of fetal electrocardiogram [ECG]).Design Retrospective case review.Setting High-risk pregnancies monitored by STAN Ò .Methods Case note review was performed in newborns with metabolic acidosis where no significant ST changes in the fetal ECG occurred prior to birth. Main outcome measures Metabolic acidosis.Results Detailed review of three cases identified poor signal quality, difficulties in CTG interpretation, failure to comply with STAN Ò clinical guidelines and deterioration of the CTG without ECG alert as the leading causes of these adverse outcomes.Conclusions The cases illustrate some of the pitfalls associated with the clinical application of the STAN Ò technology which prevent severe metabolic acidosis being eradicated completely. It may be useful to expand the STAN Ò guidelines protocol towards the identification of exceptional clinical situations, such as in our cases, and towards appropriate additional interventions, as this may lead to a further reduction in adverse neonatal outcomes.

The additional use of ST analysis for intrapartum monitoring reduced the incidence of operative vaginal deliveries and the need for fetal blood sampling but did not reduce the incidence of metabolic acidosis at birth.