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Objective:To investigate perinatal mortality, morbidity and obstetric intervention following the introduction of a universal late third-trimester ultrasound scan for growth restriction. Design:Prospective cohort study Setting:Oxfordshire (OUH), UK Population:Women with a non-anomalous singleton pregnancy undergoing pregnancy care and term delivery at OUH with an estimated date of birth between 01/Jan/2014 and 30/Sept/2019. Methods:Universal ultrasound for fetal growth restriction between 35+0and 36+6weeks was introduced in 2016. The outcomes of the next 18631 eligible term pregnancies were compared, adjusting for covariates and time, with the previous 18636 who had clinically-indicated ultrasounds only. ‘Screen positives’ for growth restriction were managed according to a pre-determined protocol which included non-intervention for some SGA babies. Main Outcome Measures:Extended perinatal mortality, a composite of mortality or encephalopathy Grade II-III, and expedited birth. Other outcomes included composite adverse outcomes used elsewhere, detection of low birthweight and birth from 37+0to 38+6weeks. Results:Extended perinatal deaths decreased 27% and severe morbidity decreased 33% but neither change was statistically significant (aOR 0.53; 00.18-1.56 and aOR 0.71; 0.31-1.63). Expedited births changed from 35.2% to 37.7% (aOR: 0.99 (0.92 – 1.06). Birthweight (thcentile) detection using fetal biometry alone was 31.4% and rose to 40.5% if all abnormal scan parameters were used. Conclusion:Improvements in mortality and severe morbidity subsequent to introducing a universal ultrasound for growth restriction are encouraging but remain unclear. Little change in intervention is possible. The antenatal detection of low birthweight remains poor but improves where markers of growth restriction are used.

Cardiotocography (CTG) is widely used to monitor fetal heart rate (FHR) during labor and assess the wellbeing of the baby. Visual interpretation of the CTG signals is challenging and computer-based methods have been developed to detect abnormal CTG patterns. More recently, data-driven approaches using deep learning methods have shown promising performance in CTG classification. However, gaps that occur due to signal noise and loss severely affect both visual and automated CTG interpretations, resulting in missed opportunities to prevent harm as well as leading to unnecessary interventions. This study utilises routinely collected CTGs from 51,449 births at term to investigate the performance of time series gap imputation techniques (GIT) when applied to FHR: Linear interpolation; Gaussian processes; and Autoregressive modelling. The implemented GITs are compared by studying their impact on the convolutional neural network (CNN) classification accuracy, as well as on their ability to correctly recover artificially introduced gaps. The Autoregressive model has been shown to be more reliable in the classification and recovery of artificial gaps when compared to the Linear and Gaussian interpolation. However, the improvement in the classification accuracy is relatively modest and does not reach statistical significance. The median (interquartile range) of sensitivity at 0.95 specificity is 0.17 (0.14,0.18) and 0.16 (0.13, 0.17) for the Autoregressive model and the zero imputations (baseline method) respectively (Mann-Whitney U = 69, P = 0.16). Future work include investigation and evaluation of other gap imputation methods to improve the classification performance of CNN on larger dataset.

Background\ud Routine third‐trimester ultrasound is frequently offered to pregnant women to identify fetuses with abnormal growth. Infrequently, a congenital anomaly is incidentally detected.\ud \ud Objective\ud To establish the prevalence and type of fetal anomalies detected during routine third‐trimester scans using a systematic review and meta‐analysis.\ud \ud Search strategy\ud Electronic databases (MEDLINE, Embase and the Cochrane library) from inception until August 2019.\ud \ud Selection criteria\ud Population‐based studies (randomised control trials, prospective and retrospective cohorts) reporting abnormalities detected at the routine third‐trimester ultrasound performed in unselected populations with prior screening. Case reports, case series, case‐control studies and reviews without original data were excluded.\ud \ud Data collection and analysis\ud Prevalence and type of anomalies detected in the third trimester. We calculated pooled prevalence as the number of anomalies per 1000 scans with 95% confidence intervals. Publication bias was assessed.\ud \ud Main results\ud The literature search identified 9594 citations: 13 studies were eligible representing 141 717 women; 643 were diagnosed with an unexpected abnormality. The pooled prevalence of a new abnormality diagnosed was 3.68 per 1000 women scanned (95% CI 2.72–4.78). The largest groups of abnormalities were urogenital (55%), central nervous system abnormalities (18%) and cardiac abnormalities (14%).\ud \ud Conclusion\ud Combining data from 13 studies and over 140 000 women, we show that during routine third‐trimester ultrasound, an incidental fetal anomaly will be found in about 1 in 300 scanned women. This information should be taken into account when taking consent from women for third‐trimester ultrasound and when designing and assessing cost of third‐trimester ultrasound screening programmes.

The ratio of maternal serum sFlt-1 (soluble fms-like tyrosine kinase 1) to PlGF (placental growth factor) has been used retrospectively to rule out the occurrence of preeclampsia, a pregnancy hypertensive disorder, within 7 days in women presenting with clinical suspicion of preeclampsia. A prospective, interventional, parallel-group, randomized clinical trial evaluated the use of sFlt-1/PlGF ratio in women presenting with suspected preeclampsia. Women were assigned to reveal (sFlt-1/PlGF result known to clinicians) or nonreveal (result unknown) arms. A ratio cutoff of 38 was used to define low (≤38) and elevated risk (>38) of developing the condition in the subsequent week. The primary end point was hospitalization within 24 hours of the test. Secondary end points were development of preeclampsia and other adverse maternal-fetal outcomes. We recruited 370 women (186 reveal versus 184 nonreveal). Preeclampsia occurred in 85 women (23%). The number of admissions was not significantly different between groups (n=48 nonreveal versus n=60 reveal; P=0.192). The reveal trial arm admitted 100% of the cases that developed preeclampsia within 7 days, whereas the nonreveal admitted 83% (P=0.038). Use of the test yielded a sensitivity of 100% (95% CI, 85.8-100) and a negative predictive value of 100% (95% CI, 97.1-100) compared with a sensitivity of 83.3 (95% CI, 58.6-96.4) and negative predictive value of 97.8 (95% CI, 93.7-99.5) with clinical practice alone. Use of the sFlt-1/PlGF ratio significantly improved clinical precision without changing the admission rate. Clinical Trial Registration- URL: http://www.isrctn.com. Unique identifier: ISRCTN87470468.

Studying the surface of an internal organ such as the placenta using three-dimensional ultrasound (3D US) is difficult. Image data from the surrounding tissue makes accurate identification of the interface technically challenging. The placental/maternal interface (basal plate) is thought to be the location of significant vascular pathology causing major maternal and fetal morbidity. We propose a new method for identifying this interface which combined with parameterisation (flattening) offers a novel way to study the vasculature of the developing placenta. © 2011 IEEE.

The cardiotocogram (CTG) is a display of the fetal heart rate and maternal uterine activity over time. An automated system for CTG analysis can be used as a decision support tool in a clinical setting. We present an automated system for the identification of abnormal patterns in the intrapartum (labor) CTG. We extract discriminating features from the CTG and then use techniques based upon the Neuroscale algorithm to project these features onto a two-dimensional visualization space. The locations of the projected features in the visualization space correlate retrospectively with an expert's assessment of the CTG's pattern.

OBJECTIVE: To determine whether the technique of fractional moving blood volume (FMBV) is applicable to Virtual Organ Computer-aided AnaLysis II (VOCAL II™)-based indices to quantify three-dimensional power Doppler ultrasound (3D-PDU) by investigating the effect of gain level on the indices measured at a possible reference point for standardization. METHODS: Ten women with singleton pregnancy between 33+3 and 37+5 weeks' gestation were recruited. The optimal position for 3D acquisition of cord insertion into the placenta was identified and static 3D-PDU volumes were acquired using consistent machine configurations. Without moving the probe or the participant changing position, successive 3D volumes were stored at -3, -5, -7 and -9 dB and at the individualized sub-noise gain (SNG) level. Volumes were excluded if flash artifact was present, in which case all five volumes were reacquired. Using 4D View software, the cord insertion was magnified and the smallest sphere possible was used to measure vascularization index (VI), flow index (FI) and vascularization flow index (VFI). The associations between VOCAL indices and gain level were assessed using Pearson's correlation coefficient. RESULTS: VOCAL indices for cord insertion correlated poorly with gain level, whether fundamental or relative to SNG level (R(2) = 0.07 and 0.04, respectively). VI was consistently 100% and mean FI and VFI were 99.5 (SD, 0.57), with all values > 97 irrespective of gain level. CONCLUSIONS: Whilst previous work has shown that gain correlates well with placental tissue VOCAL indices, the correlation between gain level and VOCAL indices in an area of 100% vascularity at the cord insertion is poor. Regions of 100% vascularity appear to be artificially assigned a value approaching 100% for all VOCAL indices irrespective of gain level. This precludes using the technique of VOCAL indices from large vessels to standardize power Doppler measurements and the FMBV index is therefore not applicable to image analysis using VOCAL.