Differences in Factors Associated With Preterm and Term Stillbirth: A Secondary Cohort Analysis of the DESiGN Trial.

OBJECTIVE: To identify whether maternal and pregnancy characteristics associated with stillbirth differ between preterm and term stillbirth. DESIGN: Secondary cohort analysis of the DESiGN RCT. SETTING: Thirteen UK maternity units. POPULATION: Singleton pregnant women and their babies. METHODS: Multiple logistic regression was used to assess whether the 12 factors explored were associated with stillbirth. Interaction tests assessed for a difference in these associations between the preterm and term periods. MAIN OUTCOME MEASURE: Stillbirth stratified by preterm (<37+0 weeks') and term (37+0-42+6 weeks') births. RESULTS: A total of 195 344 pregnancies were included. Six hundred and sixty-seven were stillborn (3.4 per 1000 births), of which 431 (65%) were preterm. Significant interactions were observed for maternal age, ethnicity, IMD, BMI, parity, smoking, PAPP-A, gestational hypertension, pre-eclampsia and gestational diabetes but not for chronic hypertension and pre-existing diabetes. Stronger associations with term stillbirth were observed in women with obesity compared to BMI 18.5-24.9 kg/m2 (BMI 30.0-34.9 kg/m2 term adjusted OR 2.1 [95% CI 1.4-3.0] vs. preterm aOR 1.1 [0.8-1.7]; BMI ≥ 35.0 kg/m2 term aOR 2.2 [1.4-3.4] vs. preterm aOR 1.5 [1.2-1.8]; p-interaction < 0.01), nulliparity compared to parity 1 (term aOR 1.7 [1.1-2.7] vs. preterm aOR 1.2 [0.9-1.6]; p-interaction < 0.01) and Asian ethnicity compared with White (p-interaction < 0.01). A weaker or lack of association with term, compared to preterm, stillbirth was observed for older maternal age, smoking and pre-eclampsia. CONCLUSION: Differences in association exist between mothers experiencing preterm and term stillbirth. These differences could contribute to design of timely surveillance and interventions to further mitigate the risk of stillbirth.

Intrapartum ultrasound for cervical dilatation: Inter- and intra-observer agreement.

INTRODUCTION: Digital vaginal examination (DVE) is considered the standard of care for assessing labor progress and cervical dilatation. However, it may be painful and is a subjective method that can increase the risk of chorioamnionitis. Known inter- and intra-observer variability exists in measurements of cervical dilatation obtained digitally. However, little is known about the inter- and intra-observer variability when using intrapartum transperineal ultrasound (TPUS). Our objectives were to investigate the relationship between cervical dilatation as assessed by TPUS and DVE. To assess inter- and intra-observer variability in both single and repeated ultrasound assessments of cervical dilatation during active labor. MATERIAL AND METHODS: This single-center study was conducted at an inner-city maternity unit in London, UK. Nulliparous participants at term with a live, singleton fetus in cephalic presentation were recruited between May 2021 and November 2022. During active labor, TPUS was performed subsequent to DVE. Repeat ultrasound assessments were performed where feasible. Participants were in a supine position, with flexed hips and knees and with an empty bladder. The ultrasound transducer was placed transversely on the maternal perineum. The anteroposterior (AP) diameter of the cervix was measured, and two-dimensional (2D) cine-loop videos were analyzed to obtain accurate measurements. Data were excluded if the time difference between DVE and TPUS exceeded 60 min. RESULTS: Of the 206 participants who consented to the study, complete data were obtained from 110 participants, yielding 147 paired TPUS and DVE observations. Ninety-six participants were excluded. The absolute difference between TPUS and DVE assessments was 0 cm in 34% of the observations, 1 cm in 46.3%, and between 2 and 4 cm in 19.7%. The mean difference was -0.9 cm (intraclass correlation coefficient = 0.85; p < 0.001). Data from 30 participants, with 50 cervical dilatation measurements, were used to assess inter- and intra-observer variability. The mean difference for the first ultrasound assessment was 0.07 cm (95% limit of agreement = -0.96 to 1.10, p < 0.001), for inter-observer variability, and 0.01 cm (95% limit of agreement = -0.29 to 0.30; p < 0.001) for intra-observer variability. CONCLUSIONS: Assessment of the cervix with TPUS during active labor is feasible and shows a strong correlation with DVE measurements. The majority of ultrasound measurements yielded readings within 1 cm of the corresponding DVE values, demonstrating high intraclass correlation and good inter- and intra-observer agreement.

Cerclage suture type to prevent pregnancy loss in women requiring a vaginal cervical cerclage: the C-STICH RCT.

Background: Second trimester miscarriage and preterm birth is a significant global problem. Surgical cervical cerclage is performed to prevent pregnancy loss and preterm birth. It utilises either a monofilament or braided suture. It is hypothesised that a braided material becomes colonised with pathogenic bacteria that causes vaginal dysbiosis, infection and cerclage failure. Objectives: The primary objective of the study was to examine the effectiveness of using a monofilament suture material as opposed to a braided suture material on pregnancy loss in women requiring a vaginal cervical cerclage. Design: Superiority open randomised controlled trial. Setting: Seventy-five maternity sites across the UK. Participants: Women experiencing a singleton pregnancy requiring a cervical cerclage. Interventions: Monofilament suture or braided suture. Main outcome measures: The primary outcome was pregnancy loss (miscarriage and perinatal mortality, including any stillbirth or neonatal death in the first week of life). Secondary outcomes included the core outcome set for preterm birth. Methods: Women were randomised on a 1 : 1 basis to monofilament or braided cerclage utilising a bespoke randomisation service with minimisation dependent on the site, indication for cerclage, intention to use progesterone and planned surgical technique. The inclusion criteria were three or more previous mid-trimester losses or preterm births, insertion of a cerclage in a previous pregnancy, a history of a mid-trimester loss or preterm birth with a shortened cervical length in the current pregnancy or in women who clinicians deemed at risk of preterm birth. The exclusion criteria were an emergency or rescue cerclage, age of < 18 years, being unable to give informed consent or the cerclage having to be placed abdominally. The original sample size was calculated based on a relative risk reduction of 41% from a pregnancy loss rate of 19% in the braided group to 11% in the monofilament group with 90% power and alpha at p = 0.05. The independent data monitoring committee noted a lower-than-anticipated pooled event rate within the trial and recommended an increase in sample size to 2050. The outcome data were collected using clinical record forms from the maternal and neonatal medical records and reported to Birmingham Clinical Trials Unit. Results: A total of 2049 women were randomised, after withdrawals and loss to follow-up, data on 1005 women in the monofilament group and 993 women in the braided group were included. The baseline demographics between the groups were similar. There was no evidence of a difference in pregnancy loss rates between the monofilament and braided groups (80/1003 vs. 75/993; adjusted risk ratio: 1.05, 95% confidence interval: 0.79 to 1.40; adjusted risk difference: 0.002, 95% confidence interval: -0.02 to 0.03). Limitations: The trial did not collect long-term paediatric outcomes. There were no safety concerns. Conclusions: There was no evidence of a difference in pregnancy loss between a monofilament suture and a braided suture. Future work: Long-term follow-up of neonates born within the C-STICH (cerclage suture type for an insufficient cervix and its effects on health outcomes) trial. Trial registration: This trial is registered as ISRCTN15373349. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 13/04/107) and is published in full in Health Technology Assessment; Vol. 28, No. 40. See the NIHR Funding and Awards website for further award information.

Cervical cerclage is an operation performed in pregnancy to prevent miscarriage and preterm birth. A cervical cerclage is sometimes recommended in women who have had babies born prematurely before or who have had previous cervical surgery. A cerclage operation involves a stitch being inserted around the neck of the womb (cervix) to keep it closed during pregnancy and to prevent it opening prematurely. When performing the operation, the doctor can use different types of threads made of different materials. The threads used to perform the operation are called sutures. One suture type is a single strand or monofilament thread, and the other is a multifilament braided thread with lots of thin strands woven together. Some evidence has suggested that using a monofilament suture thread prevented pregnancy loss by preventing infection. Therefore, we performed a randomised controlled trial of the use of monofilament suture thread versus braided suture thread, aiming to reduce pregnancy loss in women who were having a cerclage as part of their routine care. The women consented to take part in the study and were randomly allocated to their cerclage performed with either a monofilament or braided suture thread; there was no other change to their planned pregnancy care. What happened in their pregnancy was recorded from their medical records and analysed. A total of 2049 women agreed to take part in the study and consented to the analysis of their pregnancy and neonatal outcomes. Cerclage suture type for an insufficient cervix and its effects on health outcomes showed that there was no difference in pregnancy loss between the two suture threads. There was decreased maternal sepsis and decreased chorioamnionitis (which is an infection inside the womb during labour) in the women who received a monofilament suture, which needs further investigation. Although more women who had a cerclage using the monofilament thread needed a small operation and an anaesthetic, often between 36 and 37 weeks, to remove the monofilament suture prior to a vaginal birth, there were no differences in the outcomes for their babies.

A deep learning approach to identify the fetal head position using transperineal ultrasound during labor.

OBJECTIVES: To develop a deep learning (DL)-model using convolutional neural networks (CNN) to automatically identify the fetal head position at transperineal ultrasound in the second stage of labor. MATERIAL AND METHODS: Prospective, multicenter study including singleton, term, cephalic pregnancies in the second stage of labor. We assessed the fetal head position using transabdominal ultrasound and subsequently, obtained an image of the fetal head on the axial plane using transperineal ultrasound and labeled it according to the transabdominal ultrasound findings. The ultrasound images were randomly allocated into the three datasets containing a similar proportion of images of each subtype of fetal head position (occiput anterior, posterior, right and left transverse): the training dataset included 70 %, the validation dataset 15 %, and the testing dataset 15 % of the acquired images. The pre-trained ResNet18 model was employed as a foundational framework for feature extraction and classification. CNN1 was trained to differentiate between occiput anterior (OA) and non-OA positions, CNN2 classified fetal head malpositions into occiput posterior (OP) or occiput transverse (OT) position, and CNN3 classified the remaining images as right or left OT. The DL-model was constructed using three convolutional neural networks (CNN) working simultaneously for the classification of fetal head positions. The performance of the algorithm was evaluated in terms of accuracy, sensitivity, specificity, F1-score and Cohen's kappa. RESULTS: Between February 2018 and May 2023, 2154 transperineal images were included from eligible participants across 16 collaborating centers. The overall performance of the model for the classification of the fetal head position in the axial plane at transperineal ultrasound was excellent, with an of 94.5 % (95 % CI 92.0--97.0), a sensitivity of 95.6 % (95 % CI 96.8-100.0), a specificity of 91.2 % (95 % CI 87.3-95.1), a F1-score of 0.92 and a Cohen's kappa of 0.90. The best performance was achieved by the CNN1 - OA position vs fetal head malpositions - with an accuracy of 98.3 % (95 % CI 96.9-99.7), followed by CNN2 - OP vs OT positions - with an accuracy of 93.9 % (95 % CI 89.6-98.2), and finally, CNN3 - right vs left OT position - with an accuracy of 91.3 % (95 % CI 83.5-99.1). CONCLUSIONS: We have developed a DL-model capable of assessing fetal head position using transperineal ultrasound during the second stage of labor with an excellent overall accuracy. Future studies should validate our DL model using larger datasets and real-time patients before introducing it into routine clinical practice.

Does the use of angiogenic biomarkers for the management of preeclampsia and fetal growth restriction improve outcomes?: Challenging the current status quo.

Monitoring and timing of delivery in preterm preeclampsia and fetal growth restriction is one of the biggest challenges in Obstetrics. Finding the optimal time of delivery of these fetuses usually involves a trade-off between the severity of the disease and prematurity. So far, most clinical guidelines recommend the use of a combination between clinical, laboratory and ultrasound markers to guide the time of delivery. Angiogenic biomarkers, especially placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1), have gained significant attention in recent years for their potential role in the prediction and diagnosis of placenta-related disorders including preeclampsia and fetal growth restriction. Another potential clinical application of the angiogenic biomarkers is for the differential diagnosis of patients with chronic kidney disease, as this condition shares similar clinical features with preeclampsia. Consequently, angiogenic biomarkers have been advocated as tools for monitoring and deciding the optimal time of the delivery of fetuses affected by placental dysfunction. In this clinical opinion, we critically review the available literature on PlGF and sFlt-1 for the surveillance and time of the delivery in fetuses affected by preterm preeclampsia and fetal growth restriction. Moreover, we explore the use of angiogenic biomarkers for the differentiation between chronic kidney disease and superimposed preeclampsia.

Nitric oxide donor increases umbilical vein blood flow and fetal oxygenation in fetal growth restriction. A pilot study.

INTRODUCTION: To evaluate the maternal and fetal hemodynamic effects of treatment with a nitric oxide donor and oral fluid in pregnancies complicated by fetal growth restriction. METHODS: 30 normotensive participants with early fetal growth restriction were enrolled. 15 participants were treated until delivery with transdermal glyceryl trinitrate and oral fluid intake (Treated group), and 15 comprised the untreated group. All women underwent non-invasive assessment of fetal and maternal hemodynamics and repeat evaluation 2 weeks later. RESULTS: In the treated group, maternal hemodynamics improved significantly after two weeks of therapy compared to untreated participants. Fetal hemodynamics in the treated group showed an increase in umbilical vein diameter by 18.87 % (p < 0.01), in umbilical vein blood flow by 48.16 % (p < 0.01) and in umbilical vein blood flow corrected for estimated fetal weight by 30.03 % (p < 0.01). In the untreated group, the characteristics of the umbilical vein were unchanged compared to baseline. At the same time, the cerebro-placental ratio increased in the treated group, while it was reduced in the untreated group, compared to baseline values. The treated group showed a higher birthweight centile (p = 0.03) and a lower preeclampsia rate (p = 0.04) compared to the untreated group. DISCUSSION: The combined therapeutic approach with nitric oxide donor and oral fluid intake in fetal growth restriction improves maternal hemodynamics, which becomes more hyperdynamic (volume-dominant). At the same time, in the fetal circuit, umbilical vein flow increased and fetal brain sparing improved. Although a modest sample size, there was less preeclampsia and a higher birthweight suggesting beneficial maternal and fetal characteristics of treatment.

Vasa previa in singleton pregnancies: diagnosis and clinical management based on an international expert consensus.

BACKGROUND: There are limited data to guide the diagnosis and management of vasa previa. Currently, what is known is largely based on case reports or series and cohort studies. OBJECTIVE: This study aimed to systematically collect and classify expert opinions and achieve consensus on the diagnosis and clinical management of vasa previa using focus group discussions and a Delphi technique. STUDY DESIGN: A 4-round focus group discussion and a 3-round Delphi survey of an international panel of experts on vasa previa were conducted. Experts were selected on the basis of their publication record on vasa previa. First, we convened a focus group discussion panel of 20 experts and agreed on which issues were unresolved in the diagnosis and management of vasa previa. A 3-round anonymous electronic survey was then sent to the full expert panel. Survey questions were presented on the diagnosis and management of vasa previa, which the experts were asked to rate on a 5-point Likert scale (from "strongly disagree"=1 to "strongly agree"=5). Consensus was defined as a median score of 5. Following responses to each round, any statements that had median scores of ≤3 were deemed to have had no consensus and were excluded. Statements with a median score of 4 were revised and re-presented to the experts in the next round. Consensus and nonconsensus statements were then aggregated. RESULTS: A total of 68 international experts were invited to participate in the study, of which 57 participated. Experts were from 13 countries on 5 continents and have contributed to >80% of published cohort studies on vasa previa, as well as national and international society guidelines. Completion rates were 84%, 93%, and 91% for the first, second, and third rounds, respectively, and 71% completed all 3 rounds. The panel reached a consensus on 26 statements regarding the diagnosis and key points of management of vasa previa, including the following: (1) although there is no agreement on the distance between the fetal vessels and the cervical internal os to define vasa previa, the definition should not be limited to a 2-cm distance; (2) all pregnancies should be screened for vasa previa with routine examination for placental cord insertion and a color Doppler sweep of the region over the cervix at the second-trimester anatomy scan; (3) when a low-lying placenta or placenta previa is found in the second trimester, a transvaginal ultrasound with Doppler should be performed at approximately 32 weeks to rule out vasa previa; (4) outpatient management of asymptomatic patients without risk factors for preterm birth is reasonable; (5) asymptomatic patients with vasa previa should be delivered by scheduled cesarean delivery between 35 and 37 weeks of gestation; and (6) there was no agreement on routine hospitalization, avoidance of intercourse, or use of 3-dimensional ultrasound for diagnosis of vasa previa. CONCLUSION: Through focus group discussion and a Delphi process, an international expert panel reached consensus on the definition, screening, clinical management, and timing of delivery in vasa previa, which could inform the development of new clinical guidelines.

Assessment of the cerebroplacental ratio and uterine arteries in low-risk pregnancies in early labour for the prediction of obstetric and neonatal outcomes.

BACKGROUND: The evidence-based management of human labor includes the antepartum identification of patients at risk for intrapartum hypoxia. However, available evidence has shown that most of the hypoxic-related complications occur among pregnancies classified at low-risk for intrapartum hypoxia, thus suggesting that the current strategy to identify the pregnancies at risk for intrapartum fetal hypoxia has limited accuracy. OBJECTIVE: To evaluate the role of the combined assessment of the cerebroplacental ratio (CPR) and uterine arteries (UtA) Doppler in the prediction of obstetric intervention (OI) for suspected intrapartum fetal compromise (IFC) within a cohort of low-risk singleton term pregnancies in early labor. METHODS: Prospective multicentre observational study conducted across four tertiary Maternity Units between January 2016 and September 2019. Low-risk term pregnancies with spontaneous onset of labor were included. A two-step multivariable model was developed to assess the risk of OI for suspected IFC. The baseline model included antenatal and intrapartum characteristics, while the combined model included antenatal and intrapartum characteristics plus Doppler anomalies such as CPR MoM < 10th percentile and mean UtA Doppler PI MoM ≥ 95th percentile. Predictive performance was determined by receiver-operating characteristics curve analysis. RESULTS: 804 women were included. At logistic regression analysis, CPR MoM < 10th percentile (aOR 1.269, 95 % CI 1.188-1.356, P < 0.001), mean UtA PI MoM ≥ 95th percentile (aOR 1.012, 95 % CI 1.001-1.022, P = 0.04) were independently associated with OI for suspected IFC. At ROC curve analysis, the combined model including antenatal characteristics plus abnormal CPR and mean UtA PI yielded an AUC of 0.78, 95 %CI(0.71-0.85), p < 0.001, which was significantly higher than the baseline model (AUC 0.61, 95 %CI(0.54-0.69), p = 0.007) (p < 0.001). The combined model was associated with a 0.78 (95 % CI 0.67-0.89) sensitivity, 0.68 (95 % CI 0.65-0.72) specificity, 0.15 (95 % CI 0.11-0.19) PPV, and 0.98 (0.96-0.99) NPV, 2.48 (95 % CI 2.07-2.97) LR + and 0.32 (95 % CI 0.19-0.53) LR- for OI due to suspected IFC. CONCLUSIONS: A predictive model including antenatal and intrapartum characteristics combined with abnormal CPR and mean UtA PI has a good capacity to rule out and a moderate capacity to rule in OI due to IFC, albeit with poor predictive value.

Fetal face shape analysis from prenatal 3D ultrasound images.

3D ultrasound imaging of fetal faces has been predominantly confined to qualitative assessment. Many genetic conditions evade diagnosis and identification could assist with parental counselling, pregnancy management and neonatal care planning. We describe a methodology to build a shape model of the third trimester fetal face from 3D ultrasound and show how it can objectively describe morphological features and gestational-age related changes of normal fetal faces. 135 fetal face 3D ultrasound volumes (117 appropriately grown, 18 growth-restricted) of 24-34 weeks gestation were included. A 3D surface model of each face was obtained using a semi-automatic segmentation workflow. Size normalisation and rescaling was performed using a growth model giving the average size at every gestation. The model demonstrated a similar growth rate to standard head circumference reference charts. A landmark-free morphometry model was estimated to characterize shape differences using non-linear deformations of an idealized template face. Advancing gestation is associated with widening/fullness of the cheeks, contraction of the chin and deepening of the eyes. Fetal growth restriction is associated with a smaller average facial size but no morphological differences. This model may eventually be used as a reference to assist in the prenatal diagnosis of congenital anomalies with characteristic facial dysmorphisms.

Continuous non-invasive measurement of cardiac output in neonatal intensive care using regional impedance cardiography: a prospective observational study.

OBJECTIVES: To compare agreement between echocardiography and regional impedance cardiography (RIC)-derived cardiac output (CO), and to construct indicative normative ranges of CO for gestational age groups. DESIGN, SETTING AND PARTICIPANTS: Prospective cohort observational study performed in a tertiary centre in London, UK, including neonates born between 25 and 42 weeks' gestational age. EXPOSURES: Neonates on the postnatal ward had 2 hours of RIC monitoring; neonates in intensive care had RIC monitoring for the first 72 hours, then weekly for 2 hours, with concomitant echocardiography measures. MAIN OUTCOMES AND MEASURES: RIC was used to measure CO continuously. Statistical analyses were performed using R (V.4.2.2; R Core Team 2022). RIC-derived CO and echocardiography-derived CO were compared using Pearson's correlations and Bland-Altman analyses. Differences in RIC-derived CO between infants born extremely, very and late preterm were assessed using analyses of variance and mixed-effects modelling. RESULTS: 127 neonates (22 extremely, 46 very, 29 late preterm and 30 term) were included. RIC and echocardiography-measured weight-adjusted CO were correlated (r=0.62, p<0.001) with a Bland-Altman bias of -31 mL/min/kg (limits of agreement -322 to 261 mL/min/kg). The RIC-derived CO fell over 12 hours, then increased until 72 hours after birth. The 72-hour weight-adjusted mean CO was higher in extremely preterm (424±158 mL/min/kg) compared with very (325±131 mL/min/kg, p<0.001) and late preterm (237±81 mL/min/kg, p<0.001) neonates; this difference disappeared by 2-3 weeks of age. CONCLUSIONS: RIC is valid for continuous, non-invasive CO measurement in neonates. Indicative normative CO ranges could help clinicians to make more informed haemodynamic management decisions, which should be explored in future studies. TRIAL REGISTRATION NUMBER: NCT04064177.

Beetroot juice, exercise, and cardiovascular function in women planning to conceive.

OBJECTIVE: Prepregnancy optimization of cardiovascular function may reduce the risk of pre-eclampsia. We aimed to assess the feasibility and effect of preconception cardiovascular monitoring, exercise, and beetroot juice on cardiovascular parameters in women planning to conceive. DESIGN AND METHOD: Prospective single-site, open-label, randomized controlled trial. Thirty-two women, aged 18-45 years, were allocated into one of four arms (1 : 1 : 1 : 1): exercise, beetroot juice, exercise plus beetroot juice and no intervention for 12 weeks. Blood pressure (BP) was measured at home daily. Cardiac output ( CO ) and total peripheral resistance (TPR) were assessed via bio-impedance. RESULTS: Twenty-nine out of 32 (91%) participants completed the study. Adherence to daily BP and weight measurements were 81% and 78%, respectively ( n  = 29). Eight out of 15 (53%) of participants did not drink all the provided beetroot juice because of forgetfulness and taste. After 12 weeks, exercise was associated with a reduction in standing TPR (-278 ±â€Š0.272 dynes s cm -5 , P  < 0.05), and an increase in standing CO (+0.88 ±â€Š0.71 l/min, P  < 0.05). Exercise and beetroot juice together was associated with a reduction in standing DBP ( 7 ±â€Š6 mmHg, P  < 0.05), and an increase in standing CO (+0.49 ±â€Š0.66 l/min, P  < 0.05). The control group showed a reduction in standing TPR ( 313 ±â€Š387 dynes s cm -5 ) and standing DBP ( 8 ±â€Š5mmHg). All groups gained weight. CONCLUSION: Exercise and beetroot juice in combination showed a signal towards improving cardiovascular parameters. The control group showed improvements, indicating that home measurement devices and regular recording of parameters are interventions in themselves. Nevertheless, interventions before pregnancy to improve cardiovascular parameters may alter the occurrence of hypertensive conditions during pregnancy and require further investigation in adequately powered studies.

Do differences in diagnostic criteria for late fetal growth restriction matter?

BACKGROUND: Criteria for diagnosis of fetal growth restriction differ widely according to national and international guidelines, and further heterogeneity arises from the use of different biometric and Doppler reference charts, making the diagnosis of fetal growth restriction highly variable. OBJECTIVE: This study aimed to compare fetal growth restriction definitions between Delphi consensus and Society for Maternal-Fetal Medicine definitions, using different standards/charts for fetal biometry and different reference ranges for Doppler velocimetry parameters. STUDY DESIGN: From the TRUFFLE 2 feasibility study (856 women with singleton pregnancy at 32+0 to 36+6 weeks of gestation and at risk of fetal growth restriction), we selected 564 women with available mid-pregnancy biometry. For the comparison, we used standards/charts for estimated fetal weight and abdominal circumference from Hadlock, INTERGROWTH-21st, and GROW and Chitty. Percentiles for umbilical artery pulsatility index and its ratios with middle cerebral artery pulsatility index were calculated using Arduini and Ebbing reference charts. Sensitivity and specificity for low birthweight and adverse perinatal outcome were evaluated. RESULTS: Different combinations of definitions and reference charts identified substantially different proportions of fetuses within our population as having fetal growth restriction, varying from 38% (with Delphi consensus definition, INTERGROWTH-21st biometric standards, and Arduini Doppler reference ranges) to 93% (with Society for Maternal-Fetal Medicine definition and Hadlock biometric standards). None of the different combinations tested appeared effective, with relative risk for birthweight <10th percentile between 1.4 and 2.1. Birthweight <10th percentile was observed most frequently when selection was made with the GROW/Chitty charts, slightly less with the Hadlock standard, and least frequently with the INTERGROWTH-21st standard. Using the Ebbing Doppler reference ranges resulted in a far higher proportion identified as having fetal growth restriction compared with the Arduini Doppler reference ranges, whereas Delphi consensus definition with Ebbing Doppler reference ranges produced similar results to those of the Society for Maternal-Fetal Medicine definition. Application of Delphi consensus definition with Arduini Doppler reference ranges was significantly associated with adverse perinatal outcome, with any biometric standards/charts. The Society for Maternal-Fetal Medicine definition could not accurately detect adverse perinatal outcome irrespective of estimated fetal weight standard/chart used. CONCLUSION: Different combinations of fetal growth restriction definitions, biometry standards/charts, and Doppler reference ranges identify different proportions of fetuses with fetal growth restriction. The difference in adverse perinatal outcome may be modest, but can have a significant impact in terms of rate of intervention.

Placental syndromes and maternal cardiovascular health.

The placental syndromes gestational hypertension, preeclampsia and intrauterine growth restriction are associated with an increased cardiovascular risk to the mother later in life. In this review, we argue that a woman's pre-conception cardiovascular health drives both the development of placental syndromes and long-term cardiovascular risk but acknowledge that placental syndromes can also contribute to future cardiovascular risk independent of pre-conception health. We describe how preclinical studies in models of preeclampsia inform our understanding of the links with later cardiovascular disease, and how current pre-pregnancy studies may explain relative contributions of both pre-conception factors and the occurrence of placental syndromes to long-term cardiovascular disease.