Increasing trends in a low 5-min Apgar score among (near) term singletons: a Dutch nationwide cohort study.

OBJECTIVE: To investigate trends in low Apgar scores in (near) term singletons using the Dutch Perinatal Registry. METHODS: In a cohort of 1,583,188 singletons liveborn ≥35 weeks of gestation in the period 2010-2019, we studied trends in low 5-min Apgar scores (<7 and <4) using Cochrane Armitage trend tests. RESULTS: The proportion of infants with low Apgar scores <7 and <4 increased significantly between 2010-2019 (1.04-1.42% (p < 0.001), 0.17-0.19% (p = 0.009), respectively). Neonatal mortality remained unchanged. Induction of labour, epidural analgesia and planned caesarean section showed an increasing trend. Instrumental vaginal delivery and emergency caesarean section were performed less frequently over time, but these intervention subgroups showed the highest relative increase in infants with low Apgar scores. CONCLUSIONS: In the Netherlands, the risk of a low 5-min Apgar score increased over the last decade. The highest relative increase was observed in subgroups of instrumental vaginal delivery and emergency caesarean section.

Cardiotocography in practice: a qualitative study to explore obstetrical care professionals' experiences with using cardiotocography information in Dutch practice.

OBJECTIVE: This study aimed to explore obstetric care professionals' experiences with using cardiotocograph (CTG) information and how they employ this tool in their practice. DESIGN: Qualitative study, involving 30 semi-structured interviews and two focus group sessions. Conventional content analysis was used for data analysis. SETTING: Amsterdam University Medical Centers in the Netherlands. PARTICIPANTS: In total, 43 care professionals participated. The respondents included obstetricians, residents in obstetrics and gynaecology, junior physicians, clinical midwives and nurses. FINDINGS: Three main categories were identified that influenced the use of cardiotocography in practice; (1) individual characteristics involving knowledge, experience and personal beliefs; (2) teams involving collaboration in and between shifts and (3) work environment involving equipment, culture and continuing development. CONCLUSION: This study underlines the importance of teamwork when working with cardiotocography in practice. There is a particular need to create shared responsibility among team members for cardiotocography interpretation and appropriate management, which should be addressed in educational programmes and regular multidisciplinary meetings, to allow learning from colleagues' perspectives.

End-to-end learning with interpretation on electrohysterography data to predict preterm birth.

Prediction of preterm birth is a difficult task for clinicians. By examining an electrohysterogram, electrical activity of the uterus that can lead to preterm birth can be detected. Since signals associated with uterine activity are difficult to interpret for clinicians without a background in signal processing, machine learning may be a viable solution. We are the first to employ Deep Learning models, a long-short term memory and temporal convolutional network model, on electrohysterography data using the Term-Preterm Electrohysterogram database. We show that end-to-end learning achieves an AUC score of 0.58, which is comparable to machine learning models that use handcrafted features. Moreover, we evaluate the effect of adding clinical data to the model and conclude that adding the available clinical data to electrohysterography data does not result in a gain in performance. Also, we propose an interpretability framework for time series classification that is well-suited to use in case of limited data, as opposed to existing methods that require large amounts of data. Clinicians with extensive work experience as gynaecologist used our framework to provide insights on how to link our results to clinical practice and stress that in order to decrease the number of false positives, a dataset with patients at high risk of preterm birth should be collected. All code is made publicly available.

New possibilities for ST analysis - A post-hoc analysis on the Dutch STAN RCT.

BACKGROUND: The diagnostic value of ST analysis of the fetal electrocardiogram (fECG) during labor is uncertain. False alarms (ST events) may be explained by physiological variation of the fetal electrical heart axis. Adjusted ST events, based on a relative rather than an absolute rise from baseline, correct for this variation and may improve the diagnostic accuracy of ST analysis. AIMS: Determine the optimal cut-off for relative ST events in fECG to detect fetal metabolic acidosis. STUDY DESIGN: Post-hoc analysis on fECG tracings from the Dutch STAN trial (STAN+CTG branch). SUBJECTS: 1328 term singleton fetuses with scalp ECG tracing during labor, including 10 cases of metabolic acidosis. OUTCOME MEASURES: Cut-off value for relative ST events at the point closest to (0,1) in the receiver operating characteristic (ROC) curve with corresponding sensitivity and specificity. RESULTS: Relative baseline ST events had an optimal cut-off at an increment of 85% from baseline. Relative ST events had a sensitivity of 90% and specificity of 80%. CONCLUSIONS: Adjusting the current definition of ST events may improve ST analysis, making it independent of CTG interpretation.

Elevated uterine activity increases the risk of fetal acidosis at birth.

OBJECTIVE: The objective of the study was to assess the role of uterine activity on fetal outcome. STUDY DESIGN: Intrauterine pressure (IUP) recordings from consecutive term singleton, vaginal deliveries collected between June 1, 1993, and July 1, 2004, were analyzed. One thousand four hundred thirty-three recordings were included. IUP data were obtained using HP 8040A and HP M1350 cardiotocographs. For each recording the uterine contraction curve was analyzed, and the following contraction parameters were determined: relaxation time; contraction duration, frequency, amplitude, and surface; Montevideo units; and active planimeter units and contraction frequency. IUP recordings and contraction parameters from deliveries ending with an umbilical artery pH of 7.11 or less were compared with those ending with an umbilical artery pH of 7.12 or greater. Statistical analyses were performed using Student's t test and logistic regression. RESULTS: An umbilical artery pH 7.11 or less at birth is associated with significant more uterine activity during the first and second stage of labor. CONCLUSION: Increased uterine activity is significantly associated with a higher incidence of an umbilical artery pH of 7.11 or less.

The quality of intrapartum fetal heart rate monitoring.

OBJECTIVE: To determine the quality of fetal heart rate (FHR) recordings during the first and second stage of labor by quantifying the amount of fetal signal loss in relation to the method of monitoring: external ultrasound or directly via a scalp electrode. STUDY DESIGN: Analysis of 239 intrapartum recordings stored between 1 January 2001 and 1 July 2001 from consecutive deliveries at the Vrije Universiteit Medical Center in Amsterdam. Singletons delivered via the vaginal route were included in the study. FHR recordings had duration of at least 1h prior to birth of the infant. Subdivision in three groups took place on the basis of the recording technique which had been used; i.e. ultrasound, scalp electrode or a combination of both methods. FHR data was obtained using HP-M1350 cardiotocographs. The status (pen on, pen off, maternal signal) and the mode of the signals were acquired. The duration of pen lifts and maternal signals was divided by the total duration of the recording. Statistical analyses were performed with the Mann-Whitney U-test and the Wilcoxon signed ranks test. RESULTS: Recordings obtained via ultrasound demonstrated significantly more fetal signal loss than those obtained via the direct mode, particularly in the second stage. The FIGO criteria for fetal signal loss with external ultrasound were not fulfilled during this stage for about half the cases. CONCLUSION: Intrapartum FHR monitoring via a scalp electrode provides far better quality FHR signals than external ultrasound and deserves a more prominent position in fetal surveillance than it currently has.

Quality of intrapartum cardiotocography in twin deliveries.

OBJECTIVE: Intrapartum fetal heart rate (FHR) recordings in twins were compared for fetal signal loss during both stages of labor to assess the quality of these recordings by the method that had been used: external ultrasound or directly via a scalp electrode. STUDY DESIGN: Analysis of recordings collected between January 1, 1994, and January 1, 2002, from consecutive twin deliveries at the Vrije Universiteit Medical Center in Amsterdam. One hundred seventy-two twins that delivered via the vaginal route were included in the study. FHR recordings had a duration of at least 1 hour before the birth of the second twin. Subdivision took place on the basis of the recording technique, ie, ultrasound or scalp electrode. FHR data was obtained with HP-M1350 cardiotocographs. The status (pen on, pen off, maternal signal) and the mode of the signals were acquired. The duration of pen lifts and maternal signals was divided by the total duration of the recording. Statistical analyses were performed with the Mann-Whitney U test and the Wilcoxon signed ranks test. RESULTS: Recordings obtained via ultrasound demonstrated significantly more fetal signal loss than those obtained via the direct mode, particularly in the second stage. Approximately 26% to 33% of first stage and 41% to 63% of second stage ultrasound intrapartum FHR recordings in twins exceeded the International Federation of Gynecology and Obstetrics (FIGO) criteria for fetal signal loss. CONCLUSION: Intrapartum FHR monitoring via ultrasound provides far poorer quality FHR signals than the direct mode. The direct mode deserves a more prominent position in fetal surveillance than it currently has.