The incremental yield of prenatal exome sequencing over chromosome microarray for congenital heart abnormalities: A systematic review and meta-analysis.

OBJECTIVES: To determine the incremental yield of prenatal exome sequencing (PES) over standard testing in fetuses with an isolated congenital heart abnormality (CHA), CHA associated with extra-cardiac malformations (ECMs) and CHA dependent upon anatomical subclassification. METHODS: A systematic review of the literature was performed using MEDLINE, EMBASE, Web of Science and grey literature January 2010-February 2023. Studies were selected if they included greater than 20 cases of prenatally diagnosed CHA when standard testing (QF-PCR/chromosome microarray/karyotype) was negative. Pooled incremental yield was determined. PROSPERO CRD 42022364747. RESULTS: Overall, 21 studies, incorporating 1957 cases were included. The incremental yield of PES (causative pathogenic and likely pathogenic variants) over standard testing was 17.4% (95% CI, 13.5%-21.6%), 9.3% (95% CI, 6.6%-12.3%) and 35.9% (95% CI, 21.0%-52.3%) for all CHAs, isolated CHAs and CHAs associated with ECMs. The subgroup with the greatest yield was complex lesions/heterotaxy; 35.2% (95% CI 9.7%-65.3%). The most common syndrome was Kabuki syndrome (31/256, 12.1%) and most pathogenic variants occurred de novo and in autosomal dominant (monoallelic) disease causing genes (114/224, 50.9%). CONCLUSION: The likelihood of a monogenic aetiology in fetuses with multi-system CHAs is high. Clinicians must consider the clinical utility of offering PES in selected isolated cardiac lesions.

Perinatal and neonatal outcomes of high-risk asymptomatic women from a specialist preterm birth surveillance clinic.

OBJECTIVES: To report the perinatal outcomes of high-risk asymptomatic women who attended a specialist preterm surveillance clinic (PSC) to undergo screening for spontaneous preterm birth (PTB) in Ireland. METHODS: Single center, retrospective cohort study of asymptomatic high risk women who attended the PSC between January 2019 and December 2022. A comprehensive database of all patients who attended the clinic during the study period was constructed and analyzed. Overall outcomes were reported, and stratified per the occurrence of preterm or term birth. Iatrogenic PTBs were included in the outcome data. RESULTS: Following exclusions for loss-to-follow-up, 762 cases were analyzed, constituting 2262 PSC visits. Of those, 183 women were prescribed progesterone (24.0 %), and 100 women underwent cervical cerclage (13.1 %) to prevent spontaneous PTB. Overall, 2.4 %, 6.2 % and 18.6 % of participants gave birth prior to 30 weeks, 34 weeks, and 37 weeks, respectively. The median gestational age at birth for the entire cohort was 38.6 weeks (inter-quartile range (IQR) 37.2-39.6 weeks). Women who delivered < 37 weeks were significantly more likely to be smokers (p = 0.030), have a previous spontaneous PTB (p = 0.016), have multiple pregnancies (p < 0.001), type 1 or 2 diabetes (p = 0.044), or have a previous full dilatation caesarean section birth (p = 0.024). Infants born prior to 37 weeks were more likely to have a lower median birthweight (2270 vs 3300 g, p < 0.001), be admitted to a neonatal intensive care unit (53.8 % vs 2.3 %, p < 0.001) or experience short-term morbidity, including respiratory support (38.0 % vs 1.6 %, p < 0.001). CONCLUSIONS: Over 80% of women deemed to be at high risk of PTB gave birth at term gestations following attendance at a PSC during pregnancy. Most women can be successfully managed without interventions, instead employing a policy of serial cervical surveillance, to identify those at greatest risk of PTB.

Performance of QUiPP app v.2 tool for prediction of preterm birth in asymptomatic high-risk women attending preterm specialist clinic: external validation study.

OBJECTIVES: External validation of the QUiPP App v.2 algorithms in an independent cohort of high-risk asymptomatic women attending an Irish preterm birth surveillance clinic (PSC). METHODS: Retrospective, single center, observational study assessing discrimination and calibration of the QUiPP App v.2 at the six pre-determined clinical time points (birth prior to 30, 34, 37 weeks of pregnancy, and birth within one, two and four weeks of testing). Discrimination was assessed by estimating the area under the receiver-operating characteristics (ROC) curve (AUC) and sensitivity at fixed false-positive rates of 5%, 10% and 20%. Model calibration was assessed to evaluate the concordance between expected and observed outcomes. P-values <0.05 were considered statistically significant. No adjustments for treatment effects were made. RESULTS: 762 women and 1660 preterm birth surveillance clinic (PSC) visits utilizing the QUiPP between 2019 and 2022 were analyzed. The study population included 142 patients who later experienced a PTB (18.6%). QUiPP's performance to predict short-term outcomes such as birth within one week (AUC 0.866, 95% CI 0.755-0.955), two weeks (AUC 0.721, 95% CI 0.569-0.854) and four weeks (AUC 0.775, 95% CI 0.699-0.842), and delivery before 30 weeks (AUC 0.747, 95% CI 0.613-0.865) was superior to its ability to predict longer-term outcomes (birth <37 weeks; AUC 0.631, 95% CI 0.596-0.668). Calibration was generally good for low-risk results as the predicted risk in these patients tended to match the observed incidence. However, in women deemed to be at greater risk of delivery, the predicted probability superseded the observed incidence of PTB. CONCLUSION: QUiPP accurately discriminates women who are at short-term risk of PTB. A treatment paradox may influence calibration in high-risk women. Further research is needed to ascertain if QUiPP treatment thresholds can be safely adjusted in women receiving prophylactic treatment to prevent PTB, and whether this improves outcomes. This article is protected by copyright. All rights reserved.

Successful pregnancy rates amongst patients undergoing ovarian tissue cryopreservation for non-malignant indications: A systematic review and meta-analysis.

BACKGROUND: Ovarian tissue cryopreservation (OTC) is a fertility preservation method that has been clinically applied for almost 30 years. Studies specifically evaluating patients presenting with non-malignant indications for OTC and their subsequent pregnancy rates are limited. OBJECTIVE: To summarise the evidence on the rates of successful pregnancy amongst women who have undergone OTC for non-malignant indications. METHODS: A systematic review with meta-analysis (PROSPERO registration CRD42022307925) was conducted to investigate the pregnancy outcomes of patients who have undergone ovarian tissue cryopreservation for non-malignant indications. Articles published in EMBASE and Ovid MEDLINE before October 2022 were screened for inclusion based on the following criteria: original human studies pertaining to OTC with a defined non-malignant cohort and pregnancy outcomes. The successful pregnancy rates were pooled with a random-effects model of double-arcsine transformed proportions. Sensitivity analysis involved pooling the results of studies with a low risk of bias after being assessed with NIH tools. RESULTS: The database search retrieved 3,225 results, of which 16 were included in the meta-analysis. The pooled successful pregnancy rate was 23.52 % (16 studies, 95 % CI 6.48 to 44.79 %). When subgroup analysis of study types was performed, the successful pregnancy rate was higher amongst case series (47.02 %, 9 studies, 95 % CI 6.98 to 89.00 %) than cohort studies (14.64 %, 7 studies, 95 % CI 3.59 to 29.78 %). Sensitivity analysis limited to studies at low risk of bias revealed a similar pooled successful pregnancy rate of 23.35 % (12 studies, 95 % CI 2.50 to 51.96 %). CONCLUSIONS: Approximately one quarter of women who underwent OTC for non-malignant indications had a successful pregnancy. These findings are clinically important for fertility preservation counselling by providing greater evidence for more informed care.

Externally validated prediction models for pre-eclampsia: systematic review and meta-analysis.

OBJECTIVE: This systematic review and meta-analysis aimed to evaluate the performance of existing externally validated prediction models for pre-eclampsia (specifically for any- early- late-onset and preterm pre-eclampsia). METHODS: A systematic search was conducted in five databases (MEDLINE, Embase, Emcare, CINAHL, and Maternity and Infant Care Database) to identify studies based on Population, Index model, Comparator, Outcome, Timing, and Setting (PICOTS) approach until May 20, 2023. We extracted data using the CHARMS checklist and appraised risk of bias using PROBAST tool. Discrimination and calibration performance were meta-analysed when appropriate. RESULTS: Twenty-three publications reported 52 externally validated prediction models on pre-eclampsia (twenty any-onset, seventeen early-onset, fourteen late-onset, and one preterm pre-eclampsia). No model had the same set of predictors. Fifteen, two, and three any-onset pre-eclampsia models were externally validated once, twice, and thrice, respectively, and the Fetal Medicine Foundation (FMF) preterm model was widely validated in sixteen different settings. The most common predictors were maternal characteristics (pre-pregnancy BMI, prior pre-eclampsia, family history of pre-eclampsia, chronic medical conditions, and ethnicity) and biomarkers (uterine artery pulsatility index and pregnancy-associated plasma protein-A). The model for preterm pre-eclampsia (triple test FMF) had the best performances with a pooled area under the receiver operating characteristics curve (AUROC) of 0.90 (95% prediction interval (PI) 0.76 - 0.96) and was well-calibrated. The other models generally had poor to fair discrimination performance (AUROC median 0.66, range 0.53 to 0.77) and were overfitted in calibration after external validation. Apart from the FMF model, only the two most validated models in any-onset pre-eclampsia using isolated maternal characteristics, produced reasonable pooled AUROCs of 0.71 (95% PI 0.66 - 0.76) and 0.73 (0.55 - 0.86). CONCLUSION: Existing externally validated prediction models for any-, early-, and late-onset pre-eclampsia have limited discrimination and calibration performance with inconsistent input variables. The triple test FMF model had excellent discrimination performance in predicting preterm pre-eclampsia in numerous settings, but the inclusion of specialised biomarkers may limit feasibility and implementation outside of high-resource settings. This article is protected by copyright. All rights reserved.

Embryo selection through artificial intelligence versus embryologists: a systematic review.

STUDY QUESTION: What is the present performance of artificial intelligence (AI) decision support during embryo selection compared to the standard embryo selection by embryologists? SUMMARY ANSWER: AI consistently outperformed the clinical teams in all the studies focused on embryo morphology and clinical outcome prediction during embryo selection assessment. WHAT IS KNOWN ALREADY: The ART success rate is ∼30%, with a worrying trend of increasing female age correlating with considerably worse results. As such, there have been ongoing efforts to address this low success rate through the development of new technologies. With the advent of AI, there is potential for machine learning to be applied in such a manner that areas limited by human subjectivity, such as embryo selection, can be enhanced through increased objectivity. Given the potential of AI to improve IVF success rates, it remains crucial to review the performance between AI and embryologists during embryo selection. STUDY DESIGN SIZE DURATION: The search was done across PubMed, EMBASE, Ovid Medline, and IEEE Xplore from 1 June 2005 up to and including 7 January 2022. Included articles were also restricted to those written in English. Search terms utilized across all databases for the study were: ('Artificial intelligence' OR 'Machine Learning' OR 'Deep learning' OR 'Neural network') AND ('IVF' OR 'in vitro fertili*' OR 'assisted reproductive techn*' OR 'embryo'), where the character '*' refers the search engine to include any auto completion of the search term. PARTICIPANTS/MATERIALS SETTING METHODS: A literature search was conducted for literature relating to AI applications to IVF. Primary outcomes of interest were accuracy, sensitivity, and specificity of the embryo morphology grade assessments and the likelihood of clinical outcomes, such as clinical pregnancy after IVF treatments. Risk of bias was assessed using the Modified Down and Black Checklist. MAIN RESULTS AND THE ROLE OF CHANCE: Twenty articles were included in this review. There was no specific embryo assessment day across the studies-Day 1 until Day 5/6 of embryo development was investigated. The types of input for training AI algorithms were images and time-lapse (10/20), clinical information (6/20), and both images and clinical information (4/20). Each AI model demonstrated promise when compared to an embryologist's visual assessment. On average, the models predicted the likelihood of successful clinical pregnancy with greater accuracy than clinical embryologists, signifying greater reliability when compared to human prediction. The AI models performed at a median accuracy of 75.5% (range 59-94%) on predicting embryo morphology grade. The correct prediction (Ground Truth) was defined through the use of embryo images according to post embryologists' assessment following local respective guidelines. Using blind test datasets, the embryologists' accuracy prediction was 65.4% (range 47-75%) with the same ground truth provided by the original local respective assessment. Similarly, AI models had a median accuracy of 77.8% (range 68-90%) in predicting clinical pregnancy through the use of patient clinical treatment information compared to 64% (range 58-76%) when performed by embryologists. When both images/time-lapse and clinical information inputs were combined, the median accuracy by the AI models was higher at 81.5% (range 67-98%), while clinical embryologists had a median accuracy of 51% (range 43-59%). LIMITATIONS REASONS FOR CAUTION: The findings of this review are based on studies that have not been prospectively evaluated in a clinical setting. Additionally, a fair comparison of all the studies were deemed unfeasible owing to the heterogeneity of the studies, development of the AI models, database employed and the study design and quality. WIDER IMPLICATIONS OF THE FINDINGS: AI provides considerable promise to the IVF field and embryo selection. However, there needs to be a shift in developers' perception of the clinical outcome from successful implantation towards ongoing pregnancy or live birth. Additionally, existing models focus on locally generated databases and many lack external validation. STUDY FUNDING/COMPETING INTERESTS: This study was funded by Monash Data Future Institute. All authors have no conflicts of interest to declare. REGISTRATION NUMBER: CRD42021256333.

ASPRE trial: effects of aspirin on mean arterial blood pressure and uterine artery pulsatility index trajectories in pregnancy.

OBJECTIVES: The mechanism by which aspirin prevents pre-eclampsia is poorly understood, and its effects on biomarkers throughout pregnancy are unknown. We aimed to investigate the effects of aspirin on mean arterial pressure (MAP) and mean uterine artery pulsatility index (UtA-PI) using repeated measures from women at increased risk of preterm pre-eclampsia. METHODS: This was a longitudinal secondary analysis of the Combined Multimarker Screening and Randomized Patient Treatment with Aspirin for Evidence-Based Pre-eclampsia Prevention (ASPRE) trial using repeated measures of MAP and UtA-PI. In the trial, 1620 women at increased risk of preterm pre-eclampsia were identified using the Fetal Medicine Foundation algorithm at 11 + 0 to 13 + 6 weeks, of whom 798 were randomly assigned to receive 150 mg/day aspirin and 822 were assigned to receive placebo daily from 11-14 weeks to 36 weeks of gestation or delivery, whichever came first. MAP and UtA-PI were measured at baseline and follow-up visits at 19-24, 32-34 and 36 weeks of gestation. Generalized additive mixed models with treatment by gestational age interaction terms were used to investigate the effects of aspirin on MAP and UtA-PI trajectories over time. RESULTS: Among 798 participants in the aspirin group and 822 in the placebo group, there were 5951 MAP and 5942 UtA-PI measurements. Trajectories of raw and multiples of the median (MoM) values of MAP did not differ significantly between the two groups (MAP MoM analysis: P-value for treatment by gestational age interaction, 0.340). In contrast, trajectories of raw and MoM values of UtA-PI showed a significantly steeper decline in the aspirin group than in the placebo group, with the difference mainly driven by a more pronounced reduction before 20 weeks of gestation (UtA-PI MoM analysis: P-value for treatment by gestational age interaction, 0.006). CONCLUSIONS: In women at increased risk of preterm pre-eclampsia, 150 mg/day aspirin initiated in the first trimester does not affect MAP but is associated with a significant decrease in mean UtA-PI, particularly before 20 weeks of gestation. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Role of placental, fetal and maternal cardiovascular markers in predicting adverse outcome in women with suspected or confirmed pre-eclampsia.

OBJECTIVE: To assess the performance of placental, fetal and maternal cardiovascular markers in the prediction of adverse perinatal and maternal outcomes in women with suspected or confirmed pre-eclampsia. METHODS: This was a prospective prognostic accuracy study of women with suspected or confirmed pre-eclampsia who underwent a series of investigations to measure maternal hemodynamic indices, mean arterial pressure, augmentation index, ophthalmic artery peak systolic velocity (PSV) ratio, uterine artery pulsatility index (UtA-PI), fetal biometric and Doppler parameters, soluble fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF). The performance of these markers, individually or in combination, in predicting adverse perinatal and maternal outcomes was then assessed using receiver-operating-characteristics (ROC)-curve analysis. Adverse maternal outcome was defined as one or more of severe hypertension, admission to the intensive care unit, eclampsia, placental abruption, HELLP syndrome, disseminated intravascular coagulation, platelets < 100 × 109 /L, creatinine > 90 µmol/L and alanine aminotransferase > 100 U/L. Adverse perinatal outcome was defined as one or more of preterm birth at or before 34 + 0 weeks, neonatal intensive care unit admission for > 48 h, respiratory distress syndrome, intraventricular hemorrhage, hypoxic ischemic encephalopathy, necrotizing enterocolitis, retinopathy of prematurity and confirmed fetal infection. RESULTS: We recruited 126 women with suspected (n = 31) or confirmed (n = 95) pre-eclampsia at a median gestational age of 33.9 weeks (interquartile range, 30.9-36.3 weeks). Pregnancies with adverse perinatal outcome compared to those without had a higher median UtA-PI (1.3 vs 0.8; P < 0.001), ophthalmic artery PSV ratio (0.8 vs 0.7; P = 0.01) and umbilical artery PI percentile (82.0 vs 68.5; P < 0.01) and lower median estimated fetal weight percentile (4.0 vs 43.0; P < 0.001), abdominal circumference percentile (4.0 vs 63.0; P < 0.001), middle cerebral artery PI percentile (28.0 vs 58.5; P < 0.001) and cerebroplacental ratio percentile (18.0 vs 46.5; P < 0.001). Pregnancies with adverse perinatal outcome also had a higher median sFlt-1 (8208.0 pg/mL vs 4508.0 pg/mL; P < 0.001), lower PlGF (27.2 pg/mL vs 76.3 pg/mL; P < 0.001) and a higher sFlt-1/PlGF ratio (445.4 vs 74.4; P < 0.001). The best performing individual marker for predicting adverse perinatal outcome was the sFlt-1/PlGF ratio (area under the ROC curve (AUC), 0.87 (95% CI, 0.81-0.93)), followed by estimated fetal weight (AUC, 0.81 (95% CI, 0.73-0.89)). Women who experienced adverse maternal outcome had a higher median sFlt-1 level (7471.0 pg/mL vs 5131.0 pg/mL; P < 0.001) and sFlt-1/PlGF ratio (204.3 vs 93.3; P < 0.001) and a lower PlGF level (37.0 pg/mL vs 66.1 pg/mL; P = 0.01) and estimated fetal weight percentile (16.5 vs 37.0; P = 0.04). All markers performed poorly in predicting adverse maternal outcome, with sFlt-1 (AUC, 0.69 (95% CI, 0.60-0.79)) and sFlt-1/PlGF ratio (AUC, 0.69 (95% CI, 0.59-0.78)) demonstrating the best individual performance. The addition of cardiovascular, fetal or other placental indices to the sFlt-1/PlGF ratio did not improve the prediction of adverse maternal or perinatal outcomes. CONCLUSIONS: The sFlt-1/PlGF ratio performs well in predicting adverse perinatal outcomes but is a poor predictor of adverse maternal outcomes in women with suspected or diagnosed pre-eclampsia. The addition of cardiovascular or fetal indices to the model is unlikely to improve the prognostic performance of the sFlt-1/PlGF ratio. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Influence of fibroids on cell-free DNA screening accuracy.

OBJECTIVE: Cell-free DNA (cfDNA) screening assesses both maternal and placental cfDNA. Fibroids are common and release cfDNA into maternal serum. Genetic abnormality is seen in 50% of fibroids. We aimed to assess the impact of fibroids on the accuracy of genome-wide cfDNA screening. METHODS: This was a prospective cohort study of singleton pregnancies examined at one of two centers in Melbourne and Sydney, Australia, between 1 November 2019 and 31 December 2020. All cases underwent pretest ultrasound examination to confirm an ongoing pregnancy of at least 10 weeks' gestation, and, at this stage, the number and volume of any uterine fibroid were documented. Genome-wide cfDNA screening was performed to detect all copy-number variants (CNV) > 7 megabases. The incidence of a false-positive result was compared between cases with and those without fibroids. RESULTS: Over the 14-month study period, 13 184 patients underwent cfDNA screening, of whom 1017 (7.7%) had fibroids. Fibroids were not identified in any of the 17 participants who had a false-positive result for chromosomes 13, 18, 21, X or Y. Ninety-five (0.7%) cases were screen-positive for subchromosomal aberration (SA), rare autosomal trisomy (RAT) or multiple abnormalities (MA), with 10 of these cases having a fetal genetic abnormality. The incidence of a false-positive RAT, MA or SA result was significantly higher in participants with fibroids (20/1017 (2.0%)) than in those without fibroids (64/12 167 (0.5%)). Women with fibroids were approximately six times as likely to have a false-positive result for SA, and this was associated positively with both fibroid number and volume. CONCLUSIONS: Most women with fibroids do not have an abnormal result on genome-wide cfDNA screening. However, CNVs due to fibroids are associated with false-positive SA findings, although fibroids do not appear to influence cfDNA screening accuracy for the common autosomal trisomies or sex-chromosomal abnormalities. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Impact of COVID-19 pandemic restrictions on pregnancy duration and outcome in Melbourne, Australia.

OBJECTIVE: To investigate the effect of restriction measures implemented to mitigate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission during the coronavirus disease 2019 (COVID-19) pandemic on pregnancy duration and outcome. METHODS: A before-and-after study was conducted with cohort sampling in three maternity hospitals in Melbourne, Australia, including women who were pregnant when restriction measures were in place during the COVID-19 pandemic (estimated conception date between 1 November 2019 and 29 February 2020) and women who were pregnant before the restrictions (estimated conception date between 1 November 2018 and 28 February 2019). The primary outcome was delivery before 34 weeks' gestation or stillbirth. The main secondary outcome was a composite of adverse perinatal outcomes. Pregnancy outcomes were compared between women exposed to restriction measures and unexposed controls using the χ-square test and modified Poisson regression models, and duration of pregnancy was compared between the groups using survival analysis. RESULTS: In total, 3150 women who were exposed to restriction measures during pregnancy and 3175 unexposed controls were included. Preterm birth before 34 weeks or stillbirth occurred in 95 (3.0%) exposed pregnancies and in 130 (4.1%) controls (risk ratio (RR), 0.74 (95% CI, 0.57-0.96); P = 0.021). Preterm birth before 34 weeks occurred in 2.4% of women in the exposed group and in 3.4% of women in the control group (RR, 0.71 (95% CI, 0.53-0.95); P = 0.022), without evidence of an increase in the rate of stillbirth in the exposed group (0.7% vs 0.9%; RR, 0.83 (95% CI, 0.48-1.44); P = 0.515). Competing-risks regression analysis showed that the effect of the restriction measures on spontaneous preterm birth was stronger and started earlier (subdistribution hazard ratio (HR), 0.81 (95% CI, 0.64-1.03); P = 0.087) than the effect on medically indicated preterm birth (subdistribution HR, 0.89 (95% CI, 0.70-1.12); P = 0.305). The effect was stronger in women with a previous preterm birth (RR, 0.42 (95% CI, 0.21-0.82); P = 0.008) than in parous women without a previous preterm birth (RR, 0.93 (95% CI, 0.63-1.38); P = 0.714) (P for interaction = 0.044). Composite adverse perinatal outcome was less frequent in the exposed group than in controls (all women: 2.1% vs 2.9%; RR, 0.73 (95% CI, 0.54-0.99); P = 0.042); women with a previous preterm birth: 4.5% vs 8.4%; RR, 0.54 (95% CI, 0.25-1.18); P = 0.116). CONCLUSIONS: Restriction measures implemented to mitigate SARS-CoV-2 transmission during the COVID-19 pandemic were associated with a reduced rate of preterm birth before 34 weeks. This reduction was mainly due to a lower rate of spontaneous prematurity. The effect was more substantial in women with a previous preterm birth and was not associated with an increased stillbirth rate. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

ASPRE trial: risk factors for development of preterm pre-eclampsia despite aspirin prophylaxis.

OBJECTIVE: To examine the possible risk factors amongst maternal characteristics, medical and obstetric history, pre-eclampsia (PE)-specific biomarkers and estimated-risk group, according to The Fetal Medicine Foundation (FMF) algorithm, that are associated with the development of preterm PE with delivery at < 37 weeks' gestation despite aspirin prophylaxis. METHODS: This was a secondary analysis of data from the ASPRE trial. The study population consisted of women with singleton pregnancy who were deemed to be at high risk for preterm PE, based on the FMF algorithm that combines maternal factors, mean arterial pressure, uterine artery pulsatility index, serum pregnancy-associated plasma protein-A and placental growth factor (PlGF) at 11-13 weeks' gestation. High-risk women were randomized to receive aspirin (150 mg/day) vs placebo from 11-14 until 36 weeks' gestation. The primary outcome was PE with delivery at < 37 weeks' gestation (preterm PE). Multivariate logistic regression analysis was performed to identify independent predictors of preterm PE after adjusting for the use of aspirin and other covariates. RESULTS: Among 1592 high-risk women, the incidence of preterm PE was 3.0% (n = 48). The interaction between aspirin usage and history of chronic hypertension was significant in the prediction of preterm PE (P = 0.042), which indicated that there was no treatment effect in high-risk women who had chronic hypertension compared with those who did not. Adjusting for aspirin use, the interaction between aspirin and chronic hypertension and other covariates, independent predictors for the development of preterm PE were PlGF multiples of the median (MoM) (adjusted odds ratio (aOR), 0.226 (95% CI, 0.070-0.723)) and estimated-risk group based on the FMF algorithm. Compared to women with an estimated risk of 1 in 51 to 1 in 100, those with an estimated risk of 1 in 2 to 1 in 10 had a 7-fold higher risk of developing preterm PE (aOR, 6.706 (95% CI, 2.381-18.883)), and those with an estimated risk of 1 in 11 to 1 in 50 had a 3-fold higher risk of preterm PE (aOR, 2.769 (95% CI, 1.105-6.939)). PlGF MoM was an independent predictor for preterm PE among women with an estimated risk of 1 in 2 to 1 in 10 (aOR, 0.055 (95% CI, 0.005-0.668)). Among women with an estimated risk of 1 in 11 to 1 in 100, the use of aspirin was an independent predictor of preterm PE (aOR, 0.276 (95% CI, 0.111-0.689)). The cut-off for PlGF with the best performance for the prediction of preterm PE was 0.712 MoM, with an aOR of 3.677 (95% CI, 1.526-8.862). CONCLUSION: In pregnancies at high risk of preterm PE identified by screening at 11-13 weeks' gestation using the FMF algorithm, a very high-risk result (estimated risk ≥ 1 in 50), compared to an estimated risk of 1 in 51 to 1 in 100, chronic hypertension, compared to no chronic hypertension, and low PlGF concentration (< 0.712 MoM), compared to PlGF ≥ 0.712 MoM, were associated with the development of preterm PE despite aspirin prophylaxis. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Stillbirth: are we making more progress than we think? A retrospective cohort study.

OBJECTIVE: To quantify how the changing stillbirth risk profile of women is affecting the interpretation of the stillbirth rate. DESIGN: A retrospective, population-based cohort study from 1983 to 2018. SETTING: Victoria, Australia. POPULATION: A total of 2 419 923 births at ≥28 weeks of gestation. METHODS: Changes in maternal characteristics over time were assessed. A multivariable logistic regression model was developed for stillbirth, based on maternal characteristics in 1983-1987, and used to calculate individual predictive probabilities of stillbirth from the regression equation. The number of expected stillbirths per year as a result of the change in maternal demographics was then calculated, assuming no changes in care and in the associations between maternal characteristics and stillbirth over time. MAIN OUTCOME MEASURE: Stillbirth. RESULTS: Compared with 1983-1987, there were more women in older age groups giving birth, more nulliparous women, more indigenous women and women born in Oceania, Asia and Africa, more multiple pregnancies and more women with pre-existing diabetes in 2014-2018. Despite this, the rate of stillbirth fell from 5.42 per 1000 births in 1983 to 1.72 per 1000 births in 2018 (P < 0.001). Applying the multivariable logistic regression equation, derived from the 1983-87 data, to each year, had there been no changes in care or in the associations between maternal characteristics and stillbirth, the rate of stillbirth would have increased by 12%, from 4.94 per 1000 in 1983 to 5.54 per 1000 in 2018, as a result of the change in maternal characteristics. CONCLUSIONS: Population rates of stillbirth are falling faster than is generally appreciated. TWEETABLE ABSTRACT: Population reductions in stillbirth have been underestimated as a result of changing maternal characteristics.

Second- and third-trimester serum levels of growth-differentiation factor-15 in prediction of pre-eclampsia.

OBJECTIVE: Pre-eclampsia (PE) is a significant contributor to adverse maternal and perinatal outcome; however, accurate prediction and early diagnosis of this condition remain a challenge. The aim of this study was to compare serum levels of growth-differentiation factor-15 (GDF-15) at three different gestational ages between asymptomatic women who subsequently developed preterm or term PE and healthy controls. METHODS: This was a case-control study drawn from a prospective observational study on adverse pregnancy outcomes in women attending for their routine second- and third-trimester hospital visits. Serum GDF-15 was determined in 300 samples using a commercial GDF-15 enzyme-linked immunosorbent assay: 120 samples at 19-24 weeks of gestation, 120 samples at 30-34 weeks and 60 samples at 35-37 weeks. Multiple linear regression was applied to logarithmically transformed GDF-15 control values to evaluate the influence of gestational age at blood sampling and maternal characteristics on GDF-15 results. GDF-15 multiples of the normal median (MoM) values, adjusted for gestational age and maternal characteristics, were compared between pregnancies that subsequently developed preterm or term PE and healthy controls. RESULTS: Values of GDF-15 increased with gestational age. There were no significant differences in GDF-15 MoM values between cases of preterm or term PE and normotensive pregnancies at 19-24 or 35-37 weeks of gestation. At 30-34 weeks, GDF-15 MoM values were significantly increased in cases of preterm PE, but not in those who later developed term PE. Elevated GDF-15 MoM values were associated significantly with a shorter interval between sampling at 30-34 weeks and delivery with PE (P = 0.005). CONCLUSION: Serum GDF-15 levels at 19-24 or 35-37 weeks of gestation are not predictive of preterm or term PE. At 30-34 weeks, GDF-15 levels are higher in women who subsequently develop preterm PE; however, this difference is small and GDF-15 is unlikely to be useful in clinical practice when used in isolation. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Quality assessment of uterine artery Doppler measurement in first-trimester combined screening for pre-eclampsia.

OBJECTIVE: To assess the quality of mean uterine artery (UtA) pulsatility index (PI) measurement in a first-trimester pre-eclampsia screening program. METHODS: Consecutive women with a singleton pregnancy attending first-trimester screening for fetal chromosomal abnormalities also had combined screening for pre-eclampsia based on the Fetal Medicine Foundation (FMF) algorithm, at a large practice in Sydney, Australia, from May 2014 to February 2017. Distributions of mean UtA-PI multiples of the median (MoM) on a logarithmic scale were plotted in relation to the normal median with 95% CI for each operator and for each month. Central tendency and dispersion and cumulative sum charts were produced. Mean UtA-PI MoM values between 0.95 and 1.05 were considered ideal and those between 0.90 and 1.10 were considered acceptable. The screen-positive rates for preterm pre-eclampsia in different groups of sonographers according to their mean log10 UtA-PI MoM were calculated and compared using the chi-square test. RESULTS: A total of 21 010 women attended for first-trimester ultrasound and had screening for pre-eclampsia. The overall median UtA-PI MoM was 1.042 (interquartile range (IQR), 0.85-1.26). Of 46 sonographers, 42 (91.3%) performed more than 50 examinations and, of those, 41 (97.6%) measured UtA-PI within the acceptable range. Sonographers measuring UtA-PI MoM on average below 0.95 and those measuring it above 1.05 had, respectively, lower and higher screen-positive rates when compared with those with measurements within the 0.95-1.05 UtA-PI MoM interval (7.2% and 13.2% vs 11.2%, respectively, P < 0.001). CONCLUSION: UtA Doppler is measured well among trained operators when following an established protocol. While slight variations are expected, systematic error in this measurement impacts on the screen-positive rate. Therefore, a quality control process should be in place and retraining of staff may be required. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.