Uterine artery pulsatility index at 12, 22, 32 and 36 weeks' gestation in screening for pre-eclampsia

The association of persistent maternal hypotension with abnormal uterine Dopplers

OBJECTIVE

We aim to evaluate the association of persistent hypotension and abnormal placental hypoperfusion.

METHODS

We performed a secondary analysis of the Nulliparous Pregnancy Outcomes Study of patients with a singleton gestation with persistent hypotension and complete uterine artery (UtA) data. Persistent hypotension was defined as systolic blood pressure <100 mmHg and/or diastolic blood pressure <60 mmHg at all three study visits between 6 0/7 and 29 6/7 weeks gestation. The primary outcome was abnormal UtA Dopplers (pulsatility index >95th percentile for gestational age or presence of a diastolic notch) measured between 18 0/7 and 23 6/7 weeks gestation. Univariable analyses were performed to evaluate demographic and clinical associations with the primary outcome. Multivariable analyses (MVAs) were performed to adjust for potential confounders selected a priori (age, insurance status, pre-pregnancy body mass index (BMI), and history of chronic hypertension).

RESULTS

Five thousand two hundred and eighteen patients met inclusion criteria; 140 (2.7%) had persistent hypotension, 5078 (97.3%) did not. Patients in the hypotension group were less likely to be of White race and Asian ethnicity, and more likely to have public insurance and have a lower pre-pregnancy BMI, and more likely to use tobacco within 3 months of pregnancy. In unadjusted analysis, patients with persistent hypotension were more likely to have abnormal UtA Dopplers (45.0 vs. 35.3%, p value .017) but these findings did not persist in MVA (aOR 1.39, 95%CI 0.98, 1.95).

CONCLUSIONS

Patients with persistent hypotension were not at an increased risk of abnormal UtA Dopplers.

Would internal iliac artery occlusion cause gestational hypertension in the following pregnancy? A population-based study from 2008 to 2017

OBJECTIVE

In animal models, internal iliac artery occlusion caused gestational hypertension; however, whether this phenomena occurs in humans is still unknown.

MATERIALS AND METHODS

This retrospective cohort study used data from the Birth Certificate Application of Taiwan and linked to the National Health Insurance Research Database and Taiwan Maternal and Child Health Database from 2008 to 2017. Women who underwent internal iliac artery occlusion before pregnant were identified according to diagnosis and procedure codes. The occlusion group included 328 births in 286 women with a history of internal iliac artery occlusion, and the non-occlusion control group included 2,024,882 births in 1,391,288 women.

RESULTS

There were no significant differences in gestational hypertension-associated diseases including preeclampsia, eclampsia and HELLP syndrome between the occlusion and non-occlusion groups (4.3 % vs 3.4 %, p = 0.4). The adjusted odds ratios (ORs) of placental previa, placenta accreta spectrum and stillbirth were 1.69 (95 % confidence interval [CI] = 1.12-2.56), 3.99 (95 % CI = 2.52-6.31), 2.57 (95 % CI = 1.13-5.83), respectively, with the non-occlusion group as reference. The adjusted ORs of preterm delivery in the occlusion group were 1.48 (95 % CI = 1.08-2.04) and 2.79 (95 % CI = 1.62-4.82) for a gestational age below 37 weeks and 32 weeks, respectively.

CONCLUSION

Women who underwent internal iliac artery occlusion did not have a higher risk of gestational hypertension and related disease. Their offspring also had similar risks of small for gestational age, poor Apgar score, birth defects and neonatal mortality within 28 days. However, their risks of placental previa, placenta accreta spectrum, stillbirth and preterm delivery were increased.

Non-linear dose-response relationship between uterine artery pulsatility index and risk of preeclampsia in early pregnancy: A secondary analysis based on a nested cohort study

BACKGROUND

Previous studies have shown that higher uterine artery pulsatility index (UtA-PI) values in early pregnancy have predictive value for the risk of preeclampsia (PE). However, the sensitivity and specificity of this marker remain controversial. This study aims to explore further the association between UtA-PI in early pregnancy and the incidence of preeclampsia.

METHODS

A total of 5000 pregnant women who underwent prenatal examination and delivery at the same hospital were included in this nested cohort study. And the PI values of left and right uterine arteries of the subjects were obtained by transabdominal ultrasound using GE color doppler diagnostic device in early pregnancy (11-13 + 6 weeks), and finally the mean value of both was calculated and recorded as UtA-PI. Among them, 60 pregnant women developed preeclampsia and were randomly divided into a screening group (n = 12) and control group (n = 48) and matched with pregnant women who did not develop preeclampsia during the same period to form a subset for subsequent statistical analysis. A weighted multivariate logistic regression model was used to analyze the association between UtA-PI and PE. Additionally, the non-linear relationship between UtA-PI and the incidence of PE was examined using smooth curve fitting and a generalized additive model.

RESULTS

After adjusting for other variables, UtA-PI values were positively correlated with the incidence of PE, and the relationship showed a non-linear U-shaped relationship (inflection point 1.83).

CONCLUSION

Our study showed a significantly increased risk of PE when UtA-PI exceeded 1.83. This provides a basis for clinicians to identify high-risk pregnant women early and implement timely intervention, which helps to reduce maternal and fetal complications and improve health outcomes.

Role of routine uterine artery Doppler at 18-22 and 24-28 weeks' gestation following routine first-trimester screening for pre-eclampsia

OBJECTIVES

To assess the performance of mean uterine artery pulsatility index (UtA-PI) at 18-22 and 24-28 weeks of gestation in the prediction of pre-eclampsia (PE) and small-for-gestational age (SGA), and its role in reassessing the risk of PE and SGA in pregnancies screened for PE in the first trimester.

METHODS

This was a retrospective observational cohort study of 4464 women with singleton pregnancy screened routinely for PE in the first trimester, using the Gaussian algorithm, from March 2019 to May 2021, and who underwent UtA-PI assessment at 18-22 gestational weeks. Women were categorized as low risk or high risk based on the risk index obtained after first-trimester screening for PE. In high-risk patients, UtA-PI was also assessed at 24-28 weeks of gestation. Sensitivity, specificity, positive predictive value, negative predictive value (NPV), positive likelihood ratio, negative likelihood ratio and area under the receiver-operating-characteristics curve were calculated to assess the performance of UtA-PI at 18-22 and 24-28 weeks in predicting PE and SGA in the high-risk group. In all participants, different UtA-PI percentiles at 18-22 or 24-28 weeks, or their combination, were analyzed to explore their role in reassessing the risk of PE and SGA following first-trimester PE screening.

RESULTS

The performance of UtA-PI at 18-22 and 24-28 weeks in the high-risk group was good for predicting preterm PE and preterm SGA, and excellent for predicting early-onset PE and early-onset SGA, with an NPV of > 97% for all outcomes. In the low-risk group, UtA-PI ≥ 95th percentile at 18-22 weeks' gestation identified a subgroup of pregnancies with a significantly higher risk of preterm SGA compared to the low-risk group. In the high-risk group, UtA-PI < 60th percentile at 18-22 weeks' gestation, UtA-PI < 85th percentile at 24-28 weeks' gestation, and UtA-PI < 85th percentile at 24-28 weeks' gestation in women with UtA-PI ≥ 60th percentile at 18-22 weeks, identified subgroups of pregnancies with a risk of PE and SGA comparable to that of the low-risk group.

CONCLUSIONS

The performance of UtA-PI at 18-22 and 24-28 gestational weeks in high-risk pregnancies identified during first-trimester screening for PE is similar to that in the general population. The risk of PE and SGA in a high-risk cohort can be reassessed by measuring UtA-PI at 18-22 weeks, 24-28 weeks or both, allowing adjustment of follow-up, particularly de-escalation of care. © 2024 The Author(s). Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Comparison of Utero-Placental Perfusion Development From First to Second Trimester Between Low-Risk and High-Risk Pre-eclampsia Groups With Aspirin Prophylaxis

Introduction Pre-eclampsia (PE) is a common diagnosis in pregnancy and affects pregnancies worldwide. Early-onset PE often leads to severe maternal and fetal complications. Prophylactic use of aspirin (150 mg/day) before the 16th week of pregnancy can reduce the risk of PE. This study aimed to investigate the effects of maternal factors on the development of uteroplacental perfusion and fetal biometry from the first to the second trimester in a risk group receiving aspirin prophylaxis compared to a control group without Aspirin. Methods This case-control study included 448 women at high risk for PE (risk group, RG) receiving aspirin prophylaxis and 468 women at low PE risk without aspirin intake (control group, CG). Parameters recorded and considered in the first (T1) and second (T2) trimesters included uterine artery pulsatility multiple of the median (UtAPI MoM), notching at T1 and T2 and fetal biometry parameters at T2. Maternal factors were also captured, and their respective effects were examined. Results UtAPI MoM at T1 and T2 showed a significant positive correlation (r = 0.39, p < 0.001), with UtAPI MoM at T2 significantly higher for notching "yes" at T1. Pre-existing arterial hypertension and UtAPI development demonstrated a significant association (p = 0.006). Women without this risk factor showed a significantly (p < 0.001) greater decline in UtAPI development. The likelihood of notching "yes" at T2 (p < 0.001; OR: 5.80) was increased with higher UtAPI MoM at T1. The mean values (T1 and T2) of UtAPI MoM were significantly higher in the risk group than in the control group. Patients in the risk group exhibited notching at T2 (p < 0.001; OR: 5.64) more often compared to the control group. The 95% CI of the estimated fetal weight for notching "yes" at T1 was below the 50th percentile. Gestational age and head circumference/abdomen circumference (HC/AC) ratio showed a significant negative correlation (p < 0.001; b = -0.01). The control group showed significantly higher estimated fetal weights than the risk group. The HC/AC ratio in the risk group was above the HC/AC ratio in the control group but without proving significance. Conclusions Persistent notching and elevated UtAPI MoM levels in the second trimester may be risk factors for early-onset PE. Women with pre-existing arterial hypertension, notching and elevated UtAPI MoM values ​​in the first and second trimesters require special monitoring during the course of pregnancy.

A longitudinal and cross-sectional study of placental circulation between normal and placental insufficiency pregnancies

INTRODUCTION

To longitudinally and cross-sectionally study the differences in the uterine artery pulsatility index (UTPI), umbilical artery pulsatility index (UAPI) and placental vascularization indices (PVIs, derived from 3-dimensional power Doppler) between normal and placental insufficiency pregnancies throughout gestation.

METHODS

UTPI, UAPI and PVI were measured 6 times at 4- to 5- week intervals from 11 to 13+6 weeks-36 weeks. Preeclampsia (PE) and fetal growth restriction (FGR) were defined as placental insufficiency. Comparisons of UTPI, UAPI and PVI between normal and insufficiency groups were performed by one-way repeated measures analysis of variance.

RESULTS

A total of 125 women were included: monitored regularly from the first trimester to 36 weeks of gestation: 109 with normal pregnancies and 16 with placental insufficiency. Longitudinal study of the normal pregnancy group showed that UTPI and UAPI decreased significantly every 4 weeks, while PVIs increased significantly every 8 weeks until term. In the placental insufficiency group however, this decrease occurred slower at 8 weeks intervals and UTPI stabilized after 24 weeks. No significant difference was noted in PVIs throughout pregnancy. Cross-sectional study from different stages of gestation showed that UTPI was higher in the insufficiency group from 15 weeks onward and PVIs were lower after 32 weeks.

DISCUSSION

Compared to high-risk pregnancies with normal outcome, UTPI and UAPI needed a longer time to reach a significant change in those with clinical confirmation of placental insufficiency pregnancies and no significant change was found in PVI throughout gestation. UTPI was the earliest factor in detecting adverse outcome pregnancies.

Mid-trimester uterine artery Doppler for aspirin discontinuation in pregnancies at high risk for preterm pre-eclampsia: Post-hoc analysis of StopPRE trial

OBJECTIVE

To assess whether aspirin treatment can be discontinued in pregnancies with normal uterine artery pulsatility index (≤90th percentile) at 24-28 weeks.

DESIGN

Post-hoc analysis of a clinical trial.

SETTING

Nine maternity hospitals in Spain.

POPULATION OR SAMPLE

Pregnant individuals at high risk of pre-eclampsia at 11-13 weeks and normal uterine artery Doppler at 24-28 weeks.

METHODS

All participants received treatment with daily aspirin at a dose of 150 mg. Participants were randomly assigned, in a 1:1 ratio, either to continue aspirin treatment until 36 weeks (control group) or to discontinue aspirin treatment (intervention group), between September 2019 and September 2021. In this secondary analysis, women with a UtAPI >90th percentile at 24-28 weeks were excluded. The non-inferiority margin was set at a difference of 1.9% for the incidence of preterm pre-eclampsia.

MAIN OUTCOME MEASURES

Incidence of preterm pre-eclampsia.

RESULTS

Of the 1611 eligible women, 139 were excluded for UtAPI >90th percentile or if UtAPI was not available. Finally, 804 were included in this post-hoc analysis. Preterm pre-eclampsia occurred in three of 409 (0.7%) women in the aspirin discontinuation group and five of 395 (1.3%) women in the continuation group (-0.53; 95% CI -1.91 to 0.85), indicating non-inferiority of aspirin discontinuation.

CONCLUSIONS

Discontinuing aspirin treatment at 24-28 weeks in women with a UtAPI ≤90th percentile was non-inferior to continuing aspirin treatment until 36 weeks for preventing preterm pre-eclampsia.

Reference ranges of uterine artery pulsatility index from first to third trimester based on serial Doppler measurements: longitudinal cohort study

OBJECTIVE

To provide gestational-age (GA)-specific reference ranges for mean uterine artery (UtA) pulsatility index (PI) based on longitudinal data assessment throughout pregnancy.

METHODS

This was a prospective longitudinal cohort study of singleton low-risk pregnancies with adequate health and nutritional status at the time of enrolment and without fetal anomaly, receiving prenatal care between January 2018 and July 2021 at the Maternal Fetal Medicine Unit of IRCCS San Raffaele Scientific Institute, Milan, Italy. Women were recruited at ≤ 12 + 6 weeks' gestation and underwent serial standardized ultrasound monitoring, including UtA-PI measurement, by experienced certified operators until delivery. Association of UtA-PI with GA was modeled with fractional polynomial regression. Equations for mean ± SD of the estimated curves were calculated, as well as GA-specific reference charts of centiles for UtA-PI from 10 + 0 to 39 + 0 gestational weeks.

RESULTS

We included 476 healthy, low-risk pregnant women and a total of 2045 ultrasound scans (median, 4 (range, 3-9) per patient) were available for analysis. Mean UtA-PI was 1.84 ± 0.55, 1.07 ± 0.38 and 0.78 ± 0.23 in the first, second and third trimesters of pregnancy, respectively. Goodness-of-fit assessment revealed that second-degree smoothing was the most accurate fractional polynomial for describing the course of UtA-PI throughout gestation; therefore, it was modeled in a multilevel framework for the construction of UtA-PI curves. We observed a rapid and substantial decrease in mean UtA-PI before 16 weeks, with subsequent smoother decrement of the slope and more stable values from 20 until 39 weeks. The 3rd , 5th , 10th , 25th , 50th , 75th , 90th , 95th and 97th centiles according to GA for UtA-PI are provided, as well as equations to allow calculation of any value as a centile.

CONCLUSIONS

UtA-PI shows a progressive non-linear decrease throughout pregnancy. The new reference ranges for GA-specific mean UtA-PI constructed using rigorous methodology may have a better performance compared with previous models for screening for placenta-associated diseases in the early stages of pregnancy and for evaluating the potential risk for pregnancy-induced hypertension and/or small-for-gestational age later in pregnancy. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Uterine artery Doppler indices throughout gestation in women with and without previous Cesarean deliveries: a prospective longitudinal case-control study

To determine whether a history of previous Cesarean delivery (CD) impacts uterine artery (UtA) Doppler indices throughout pregnancy. Women with and without CD (NCD) were prospectively enrolled for sequential assessments of the UtA mean/median pulsatility index (UtA-PI), resistance index (UtA-RI), and systolic/diastolic ratio (UtA-S/D) at 11-13 + 6, 14-19 + 6, 30-34 + 6, and 35-37 + 6 weeks' gestation. Data from 269/269, 246/257, 237/254, and 219/242 CD/NCD participants from each gestational period were available for analysis. Multiples of the median (MoMs) of UtA Doppler indices showed biphasic temporal (Δ) pattern; with an initial dropping until the second trimester, then a subsequent elevation until late in pregnancy (p < 0.05). The measurements and Δs of the UtA indices between CD and NCD were not different (p > 0.05). Mixed-effects modelling ruled out effects from nulliparity (n = 0 and 167 for CD and NCD, respectively) (p > 0.05). History of CD neither influenced the measurements nor the temporal changes of the UtA Doppler indices throughout pregnancy. The biphasic Δs of UtA Doppler indices added to the longitudinal data pool, and may aid in future development of a more personalized prediction using sequential/contingent methodologies, which may reduce the false results from the current cross-sectional screening.

Clinical workflow of sonographers performing fetal anomaly ultrasound scans: deep-learning-based analysis

OBJECTIVE

Despite decades of obstetric scanning, the field of sonographer workflow remains largely unexplored. In the second trimester, sonographers use scan guidelines to guide their acquisition of standard planes and structures; however, the scan-acquisition order is not prescribed. Using deep-learning-based video analysis, the aim of this study was to develop a deeper understanding of the clinical workflow undertaken by sonographers during second-trimester anomaly scans.

METHODS

We collected prospectively full-length video recordings of routine second-trimester anomaly scans. Important scan events in the videos were identified by detecting automatically image freeze and image/clip save. The video immediately preceding and following the important event was extracted and labeled as one of 11 commonly acquired anatomical structures. We developed and used a purposely trained and tested deep-learning annotation model to label automatically the large number of scan events. Thus, anomaly scans were partitioned as a sequence of anatomical planes or fetal structures obtained over time.

RESULTS

A total of 496 anomaly scans performed by 14 sonographers were available for analysis. UK guidelines specify that an image or videoclip of five different anatomical regions must be stored and these were detected in the majority of scans: head/brain was detected in 97.2% of scans, coronal face view (nose/lips) in 86.1%, abdomen in 93.1%, spine in 95.0% and femur in 92.3%. Analyzing the clinical workflow, we observed that sonographers were most likely to begin their scan by capturing the head/brain (in 24.4% of scans), spine (in 23.2%) or thorax/heart (in 22.8%). The most commonly identified two-structure transitions were: placenta/amniotic fluid to maternal anatomy, occurring in 44.5% of scans; head/brain to coronal face (nose/lips) in 42.7%; abdomen to thorax/heart in 26.1%; and three-dimensional/four-dimensional face to sagittal face (profile) in 23.7%. Transitions between three or more consecutive structures in sequence were uncommon (up to 13% of scans). None of the captured anomaly scans shared an entirely identical sequence.

CONCLUSIONS

We present a novel evaluation of the anomaly scan acquisition process using a deep-learning-based analysis of ultrasound video. We note wide variation in the number and sequence of structures obtained during routine second-trimester anomaly scans. Overall, each anomaly scan was found to be unique in its scanning sequence, suggesting that sonographers take advantage of the fetal position and acquire the standard planes according to their visibility rather than following a strict acquisition order. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Non-invasive monitoring of blood oxygenation in human placentas via concurrent diffuse optical spectroscopy and ultrasound imaging

Direct assessment of blood oxygenation in the human placenta can provide information about placental function. However, the monitoring of placental oxygenation involves invasive sampling or imaging techniques that are poorly suited for bedside use. Here we show that placental oxygen haemodynamics can be non-invasively probed in real time and up to 4.2 cm below the body surface via concurrent frequency-domain diffuse optical spectroscopy and ultrasound imaging. We developed a multimodal instrument to facilitate the assessment of the properties of the anterior placenta by leveraging image-reconstruction algorithms that integrate ultrasound information about the morphology of tissue layers with optical information on haemodynamics. In a pilot investigation involving placentas with normal function (15 women) or abnormal function (9 women) from pregnancies in the third trimester, we found no significant differences in baseline haemoglobin properties, but statistically significant differences in the haemodynamic responses to maternal hyperoxia. Our findings suggest that the non-invasive monitoring of placental oxygenation may aid the early detection of placenta-related adverse pregnancy outcomes and maternal vascular malperfusion.

Endometriosis and Impaired Placentation: A Prospective Cohort Study Comparing Uterine Arteries Doppler Pulsatility Index in Pregnancies of Patients with and without Moderate-Severe Disease

The aim of this study was to evaluate if moderate-severe endometriosis impairs uterine arteries pulsatility index (UtA-PI) during pregnancy when compared to unaffected controls. In this prospective cohort study, pregnant women with stage III-IV endometriosis according to the revised American Fertility Society (r-AFS) classification were matched for body mass index and parity in a 1:2 ratio with unaffected controls. UtA-PIs were assessed at 11-14, 19-22 and 26-34 weeks of gestation following major reference guidelines. A General Linear Model (GLM) was implemented to evaluate the association between endometriosis and UtA-PI Z-scores. Significantly higher third trimester UtA-PI Z-scores were observed in patients with r-AFS stage III-IV endometriosis when compared to controls (p = 0.024). In the GLM, endometriosis (p = 0.026) and maternal age (p = 0.007) were associated with increased third trimester UtA-PI Z-scores, whereas conception by in-vitro fertilization with frozen-thawed embryo transfer significantly decreased UtA-PI measures (p = 0.011). According to these results, r-AFS stage III-IV endometriosis is associated with a clinically measurable impaired late placental perfusion. Closer follow-up may be recommended in pregnant patients affected by moderate-severe endometriosis in order to attempt prediction and prevention of adverse pregnancy and perinatal outcomes due to a defective late placental perfusion.

Uterine Artery Pulsatility Index as a Pre-eclampsia Predictor in the 3 Trimesters in Women with Singleton Pregnancies

OBJECTIVE

 To evaluate the mean uterine artery pulsatility index (UtAPI) in each trimester of pregnancy as a predictor of early or late pre-eclampsia (PE) in Colombian pregnant women.

METHODS

 The UtAPI was measured in singleton pregnancies in each trimester. Uterine artery pulsatility index as predictor of PE was evaluated by odds ratio (OR), receiver operating characteristic (ROC) curves, and Kaplan-Meier diagram.

RESULTS

 Analysis in the 1^st and 3^rd trimester showed that abnormal UtAPI was associated with early PE (OR: 5.99: 95% confidence interval [CI]: 1.64-21.13; and OR: 10.32; 95%CI: 2.75-42.49, respectively). Sensitivity and specificity were 71.4 and 79.6%, respectively, for developing PE (area under the curve [AUC]: 0.922). The Kaplan-Meier curve showed that a UtAPI of 0.76 (95%CI: 0.58-1.0) in the 1^st trimester was associated with early PE, and a UtAPI of 0.73 (95%CI: 0.55-0.97) in the 3^rd trimester was associated with late PE.

CONCLUSION

 Uterine arteries proved to be a useful predictor tool in the 1^st and 3^rd trimesters for early PE and in the 3^rd trimester for late PE in a pregnant population with high prevalence of PE.

Mean arterial pressure for predicting preeclampsia in Asian women: a longitudinal cohort study

OBJECTIVE

Previous studies suggested mean arterial pressure (MAP) had moderate predictive values in the first and second trimesters for the prediction of preeclampsia. However, the performance of MAP in Asian women is still unclear. The objective of this study was to examine the predictive values of MAP in Asian population throughout gestation, and to compare the performance of MAP, angiogenic factors and uterine artery Doppler in the prediction of preeclampsia.

DESIGN

A prospective cohort study.

SETTING

KK Women's and Children's Hospital, Singapore.

PARTICIPANTS

A total of 926 women with singleton pregnancy less than 14 weeks of gestation were included in the prospective Neonatal and Obstetrics Risks Assessment cohort between September 2010 and October 2014. Maternal blood pressure levels, uterine artery pulsatility index (UtA-PI), serum soluble fms-like tyrosine kinase 1 (sFlt-1), placental growth factor (PlGF) and sFlt-1/PlGF ratio were measured at 11-14, 18-22, 28-32 and 34 weeks onward, respectively.

PRIMARY AND SECONDARY OUTCOMES

Preeclampsia was the main pregnancy outcome.

RESULTS

A total of 20 women developed preeclampsia, who had significantly lower levels of PlGF, higher levels of sFlt-1/PlGF ratio and MAP throughout pregnancy than women without preeclampsia. Compared with angiogenic factors and UtA-PI, MAP had significantly higher area under the receiver operating characteristic curves (AUCs) for predicting preeclampsia and term preeclampsia throughout gestation. For predicting preeclampsia, MAP had AUCs of 0.86 (95% CI 0.78 to 0.95), 0.87 (95% CI 0.80 to 0.95) and 0.91 (95% CI 0.85 to 0.98) at 11-14, 18-22 and 28-32 weeks, respectively. For predicting term preeclampsia, MAP yielded AUCs of 0.87 (95% CI 0.75 to 0.99), 0.87 (95% CI 0.76 to 0.98) and 0.90 (95% CI 0.80 to 0.99) at 11-14, 18-22 and 28-32 weeks, respectively. For predicting preterm preeclampsia, the performance of MAP and PlGF was similar.

CONCLUSION

MAP is a good predictor for preeclampsia, especially term preeclampsia, in Asian women.

Prospective longitudinal cohort study of uterine arteries Doppler in singleton pregnancies obtained by IVF/ICSI with oocyte donation or natural conception

STUDY QUESTION

Do uterine arteries Doppler studies show different pulsatility index (UtA-PI) measurements in IVF/ICSI pregnancies with oocyte donation (OD) as compared to natural conceptions?

SUMMARY ANSWER

In IVF/ICSI pregnancies with OD, UtA-PI is reduced by an average of about 40% as compared to pregnancies with natural conception.

WHAT IS KNOWN ALREADY

OD pregnancies present worse pregnancy outcomes as compared to natural conception, particularly for increased incidence of pre-eclampsia (PE). Recent evidence shows that IVF/ICSI pregnancies with frozen blastocyst transfer also present higher prevalence of PE and 15% lower UtA-PI as compared to pregnancies after fresh blastocyst transfers.

STUDY DESIGN, SIZE, DURATION

Prospective, longitudinal matched cohort study performed in the Fetal Medicine and Obstetric Departments of San Raffaele Hospital in Milan, between 2013 and 2018. The analysis is based on 584 Doppler observations collected from 296 women with different method of conception (OD n = 122; natural conception n = 174).

PARTICIPANTS/MATERIALS, SETTING, METHODS

IVF/ICSI viable singleton pregnancies with OD and natural conception control pregnancies matched for BMI and smoking, performing repeated UtA-PI measurements at 11-34 weeks. Miscarriages, abnormalities, twins, significant maternal diseases and other types of ARTs were excluded. Log mean left-right UtA-PI was used for analysis with linear mixed model (LMM) and correction for significant confounders. Pregnancy outcome was also analyzed.

MAIN RESULTS AND THE ROLE OF CHANCE

Participants after OD were older and more frequently nulliparous (mean age: OD 43.4, 95% CI from 42.3 to 44.6; natural conception 35.1, 95% CI from 34.5 to 35.7; P-value < 0.001; nulliparous: OD 96.6%; natural conception 56.2%; P-value < 0.001). Mean pulsatility index was lower in OD (UtA-PI: natural conception 1.22; 95% CI from 1.11 to 1.28; OD 1.04; 95% CI from 0.96 to 1.12; P-value < 0.001). A significant effect of parity, gestational age (GA) modeled with a cubic polynomial and BMI was described in the LMM. The mean Log UtA-PI was on average 37% lower in OD as compared to natural conception pregnancies at LMM (P-value < 0.001). We also found a significant interaction between longitudinal UtA-PI Doppler and GA. Therefore, at 11 weeks' gestation the Log UtA-PI was 42% lower and, at 34 weeks, the differences reduced to 32%. GA at delivery and birth weight were statistically lower in OD group; however, birthweight centile was not statistically different. Preeclampsia was 11-fold more common in the OD group (0.6% and 6.6%, P-value = 0.003). No other significant difference in pregnancy outcome was shown in the study groups (gestational diabetes mellitus, small or large for GA).

LIMITATIONS, REASONS FOR CAUTION

It was not possible to properly match for maternal age and to blind the assessment given the major differences between cohorts; however, we did not find significant within-groups effects related to maternal age. Future research is needed to reassess outcomes and correct them for maternal characteristics (e.g. cardiovascular function).

WIDER IMPLICATIONS OF THE FINDINGS

This finding reproduces our previous discovery of lower UtA-PI in frozen as compared to fresh blastocyst transfer. The vast majority of OD is obtained by the use of cryopreservation. We speculate that increased uterine perfusion may be the physiological response to compensate dysfunctions both in the mother and in the placenta.

STUDY FUNDING/COMPETING INTEREST(S)

This is a non-funded study. The authors do not declare competing interest.

TRIAL REGISTRATION NUMBER

N/A.

Fetal cardiac function at 35-37 weeks' gestation in pregnancies that subsequently develop pre-eclampsia

OBJECTIVE

To compare fetal cardiac morphology and function between pregnancies that subsequently developed pre-eclampsia (PE) and those that remained normotensive.

METHODS

This was a prospective observational study in 1574 pregnancies at 35-37 weeks' gestation, including 76 that subsequently developed PE. We carried out comprehensive assessment of fetal cardiac morphology and function including novel imaging modalities, such as speckle-tracking echocardiography, and measured uterine artery pulsatility index, mean arterial pressure (MAP), serum placental growth factor (PlGF), soluble fms-like tyrosine kinase-1 (sFlt-1) and cerebroplacental ratio (CPR). The findings in the group that subsequently developed PE were compared to those in pregnancies that remained normotensive.

RESULTS

In fetuses of mothers who subsequently developed PE, compared to those from normotensive pregnancies, there was a more globular right ventricle, as shown by reduced right ventricular sphericity index, reduced right ventricular systolic contractility, as shown by reduced global longitudinal strain, and reduced left ventricular diastolic function, as shown by increased E/A ratio. On multivariable regression analysis, these indices demonstrated an association with PE, independent of maternal characteristics and fetal size. In pregnancies that subsequently developed PE, compared to those that remained normotensive, MAP, sFlt-1 and the incidence of low birth weight were higher, whereas serum PlGF, CPR and the interval between assessment and delivery were lower. These findings demonstrate that, in pregnancies that develop PE, there is evidence of impaired placentation, reflected in low PlGF and reduced birth weight, placental ischemia, evidenced by increased sFlt-1 which becomes apparent in the interval of 2-4 weeks preceding the clinical onset of PE, and consequent fetal hypoxia-induced redistribution in the fetal circulation, reflected in the low CPR.

CONCLUSION

Although the etiology of the observed fetal cardiac changes in pregnancies that subsequently develop PE remains unclear, it is possible that the reduction in right-heart systolic function is the consequence of high afterload due to increased placental resistance, whilst the early left ventricular diastolic changes could be due to fetal hypoxia-induced redistribution in the fetal circulation. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

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.

Serum leukotriene B4 and hydroxyeicosatetraenoic acid in the prediction of pre-eclampsia

INTRODUCTION

Pre-eclampsia (PE) affects 2-8% of pregnancies worldwide. Despite identification of numerous possible biomarkers, accurate prediction and early diagnosis of PE remain challenging. We examined the potential of leukotriene B4 (LTB4) and 15-hydroxyeicosatetraenoic acid (15(S)-HETE) as biomarkers of PE by comparing serum levels at three gestational age (GA) groups between normotensive pregnancies and asymptomatic women who subsequently developed preterm or term-PE.

METHODS

This is a case-control study drawn from a prospective study of adverse pregnancy outcomes with serum samples collected at 19-24 weeks (n = 48), 30-34 weeks (n = 101) and 35-37 weeks (n = 54) GA. LTB4 and 15(S)-HETE levels were determined by ELISA. Serum level multiples of the median (MoM) were compared between normal and PE-pregnancies. Association between LTB4 and 15(S)-HETE and GA at delivery was investigated with Cox proportional-hazards models.

RESULTS

Serum LTB4 levels were lower in women of East-Asian ethnicity, higher in women with PE history, and increased with GA in normotensive pregnancies, but not in PE. LTB4 was elevated at 19-24 weeks in women who developed preterm-PE. There was a negative association between LTB4 MoM and interval between sampling and delivery with PE at 19-24 weeks only. Serum 15(S)-HETE levels were not influenced by GA at testing and were elevated in women of South-Asian ethnicity. Median 15(S)-HETE levels were unchanged in preterm and term-PE at any GA.

DISCUSSION

LTB4 was higher at 19-24 weeks in pregnancies that developed preterm-PE versus unaffected pregnancies, suggesting it is a potentially useful predictive marker of preterm PE in the second trimester.

Preeclampsia may influence offspring neuroanatomy and cognitive function: a role for placental growth factor†

Preeclampsia (PE) is a common pregnancy complication affecting 3-5% of women. Preeclampsia is diagnosed clinically as new-onset hypertension with associated end organ damage after 20 weeks of gestation. Despite being diagnosed as a maternal syndrome, fetal experience of PE is a developmental insult with lifelong cognitive consequences. These cognitive alterations are associated with distorted neuroanatomy and cerebrovasculature, including a higher risk of stroke. The pathophysiology of a PE pregnancy is complex, with many factors potentially able to affect fetal development. Deficient pro-angiogenic factor expression is one aspect that may impair fetal vascularization, alter brain structure, and affect future cognition. Of the pro-angiogenic growth factors, placental growth factor (PGF) is strongly linked to PE. Concentrations of PGF are inappropriately low in maternal blood both before and during a PE gestation. Fetal concentrations of PGF appear to mirror maternal circulating concentrations. Using Pgf-/- mice that may model effects of PE on offspring, we demonstrated altered central nervous system vascularization, neuroanatomy, and behavior. Overall, we propose that development of the fetal brain is impaired in PE, making the offspring of preeclamptic pregnancies a unique cohort with greater risk of altered cognition and cerebrovasculature. These individuals may benefit from early interventions, either pharmacological or environmental. The early neonatal period may be a promising window for intervention while the developing brain retains plasticity.

The competing risk approach for prediction of preeclampsia

The established method of the assessment of the risk for development of preeclampsia is to identify risk factors from maternal demographic characteristics and medical history; in the presence of such factors, the patient is classified as high risk and in their absence as low risk. Although this approach is simple to perform, it has poor performance of the prediction of preeclampsia and does not provide patient-specific risks. This review describes a new approach that allows the estimation of patient-specific risks of delivery with preeclampsia before any specified gestational age by maternal demographic characteristics and medical history with biomarkers obtained either individually or in combination at any stage in pregnancy. In the competing risks approach, every woman has a personalized distribution of gestational age at delivery with preeclampsia; whether she experiences preeclampsia or not before a specified gestational age depends on competition between delivery before or after the development of preeclampsia. The personalized distribution comes from the application of Bayes theorem to combine a previous distribution, which is determined from maternal factors, with likelihoods from biomarkers. As new data become available, what were posterior probabilities take the role as the previous probability, and data collected at different stages are combined by repeating the application of Bayes theorem to form a new posterior at each stage, which allows for dynamic prediction of preeclampsia. The competing risk model can be used for precision medicine and risk stratification at different stages of pregnancy. In the first trimester, the model has been applied to identify a high-risk group that would benefit from preventative therapeutic interventions. In the second trimester, the model has been used to stratify the population into high-, intermediate-, and low-risk groups in need of different intensities of subsequent monitoring, thereby minimizing unexpected adverse perinatal events. The competing risks model can also be used in surveillance of women presenting to specialist clinics with signs or symptoms of hypertensive disorders; combination of maternal factors and biomarkers provide patient-specific risks for preeclampsia that lead to personalized stratification of the intensity of monitoring, with risks updated on each visit on the basis of biomarker measurements.

The need for implementation of first trimester screening for preeclampsia and fetal growth restriction in low resource settings

Background: Preeclampsia [PE] and fetal growth restriction [FGR] is a major cause of perinatal morbidity in both developed and developing countries but the disease leaves a severe impact in developing countries, due to the late presentation of cases where prevention and treatment becomes impossible. Routine antenatal ultrasound and health checkups in periphery are usually done in first trimester for dating and viability scan, in midtrimester for anomaly scan and in third trimester for safe confinement. Underlying disorder of deep placentation which is unidentified can lead to increased maternal morbidity and fetal compromise between 26 to 34 weeks of gestation The complications present at an irreversible stage where there is no sufficient time even for referral to tertiary care center. Frequent antenatal visits as suggested by WHO would definitely bring down maternal mortality but this increased surveillance when offered to all might be a huge burden to health care providers in low resource settings. An acceptable screening test should help in triaging the high risk group in first trimester itself targeting about only one third of the population for prophylactic therapy and increased antenatal surveillance.The objective of this study is to evaluate the performance and feasibility of different screening protocols in low resource settings.Methodology: Screening for PE and FGR was done at the 11-14 weeks aneuploidy scan as per FMF guidelines. Group I included 6289 women whose risk prediction was done with maternal characteristics [MC], mean arterial pressure [MAP] and Uterine artery Doppler [UAD]. Group II included 2067 women whose risk was predicted with MC, MAP, UAD and PAPP-A. Group III included 576 women whose risk prediction included all parameters with PLGF.Results: Two thousand five hundred fifty-seven cases were screen positive in group I and 602 were screen positive in group II. In group III which included PLGF, 24 were positive for early onset PE and 36 for late onset PE. The number needed to treat [NNT] was 35.9, 29.1 and 10% in Group I, II and III respectively. The detection rate [DR] for PE and FGR was 60% in Group I and DR for FGR in Group II was 85%. In Group III, for early onset PE the DR was 98% and 68% for late onset PE.Conclusion: Screening for PE with available resources in the periphery needs to be implemented to avoid its grave complications. Traditional screening for PE by NICE guidelines can be adopted but may have a detection rate of only 30-40%. Though screening by ACOG criteria may have good detection rates but more than two thirds of the population would become screen positive which nullifies this approach as a good screening methodology in low resource settings. Multiparametric approach for screening in first trimester serves as a better screening tool to enable higher detection rate of disease with least false positive rates. Uterine artery Doppler when combined with maternal characteristics and mean arterial pressure could achieve a detection rate of about 60% and would still target only one third of the population for increased antenatal surveillance. This requires training healthcare professionals in the periphery for this approach and this should be our prime focus in the current scenario. Inclusion of serum biochemistry would still bring down the target population to 10% and increase the DR and can be considered as an additional test in economically feasible population. In low resource settings a better screening approach to PE would be a combination of maternal history, biophysical or biochemical parameters whichever is feasible considering the economy and availability of resources.

The Transverse versus the Sagittal Approach in First-Trimester Uterine Artery Doppler Measurement

Objective

The uterine artery pulsatility index (UtA-PI) is an important marker for predicting and assessing the risk of various complications such as pre-eclampsia and fetal growth restriction. The measurement of UtA-PI in the first trimester is usually conducted via the sagittal approach. The aim of this study was to evaluate UtA Doppler measurement using the transverse approach in the first trimester.

Methods

This was a prospective observational study of 50 women with singleton pregnancy at between 11-13+6 weeks of gestation. Uterine artery (UtA) Doppler variables were measured using both the transverse and sagittal approach. The two approaches were compared in terms of time required to complete the measurements and early diastolic notch. The sample t-test and Wilcoxon rank sign test were used to analyze the outcomes when appropriate. Bland-Altman plots were used to determine the agreement between the two approaches. A P-value <0.05 was considered statistically significant. Intra-class correlation (ICC) was used to evaluate the reliability of measurements.

Results

There were a total of 50 pregnant women who participated in the study and completed the study protocol. The mean age of all subjects was 29.6 years, and 24 (48%) were nulliparous. We observed no difference in terms of mean UtA-PI between the two approaches (sagittal: 2.04, transverse: 2.03; mean difference 0.01, CI -0.01, 0.04; p>0.309), nor in the means of any other UtA variables. However, there were differences between the two approaches in terms of early diastolic notch (sagittal: 11, transverse: 13; p>0.999) and the mean time required to complete the measurements (transverse: 21.7 s, sagittal: 24.3 s; p=0.001). The intra-class correlation coefficients (ICCs) were 0.985, 0.963, and 0.988 for the right, left, and mean UtA-PIs respectively.

Conclusion

The transverse approach at a bladder depth of less than 5 cm performed better than the sagittal approach in the measurement of first-trimester uterine arteries. It may, thus, may be useful as a complementary approach in cases in which there is difficulty obtaining measurements using the sagittal approach.

Prediction of pregnancy complications by second-trimester uterine artery Doppler assessment in monochorionic twins

PURPOSE

We aimed to investigate whether transabdominal uterine artery (UtA) pulsatility index (PI) differs between monochorionic (MC) diamniotic and dichorionic (DC) twins and is useful to predict pregnancy complications.

METHODS

A total of 406 uncomplicated twin pregnancies (94 MC, 312 DC) were examined at 22⁺⁰ -24⁺⁶ weeks and compared for demographic characteristics, mean UtA PI, presence of notch, development of preeclampsia, fetal growth restriction (FGR), placental abruption, intrauterine fetal death and preterm delivery. Mann-Whitney and Fisher's exact tests were performed for continuous and categorical variables, respectively. Sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratio were calculated for mean PI >95th percentile, presence of notch, and presence of either elevated PI or notch.

RESULTS

Median mean UtA PI was 0.68 in DC and 0.75 in MC pregnancies (P = .005). Bilateral notches were observed in one MC pregnancy; unilateral notch was seen in 8 DC (2.6%) and 5 MC diamniotic (5.3%) pregnancies. FGR occurred more frequently in DC twin pregnancies, while intrauterine fetal death in MC. Overall, the sensitivity of the parameters tested was low. Pregnancies with both PI above 95th percentile and presence of notch were all associated with complications, particularly FGR.

CONCLUSION

MC pregnancies have higher mean UtA PI. UtA screening in twins shows lower performances than in singletons for the detection of complications.

Early prediction of preeclampsia and small-for-gestational-age via multi-marker model in Chinese pregnancies: a prospective screening study

BACKGROUND

Recent evidence suggests early screening of preeclampsia and small-for-gestational-age (SGA) would benefit pregnancies followed by subsequent prophylactic use of aspirin. Multi-marker models have shown capability of predicting preeclampsia and SGA in first trimester. Yet the clinical feasibility of combined screening model for Chinese pregnancies has not been fully assessed. The aim of this study is to evaluate the applicability of a multi-marker screening model to the prediction of preeclampsia and SGA in first trimester particularly among Chinese population.

METHODS

Three thousand two hundred seventy pregnancies meeting the inclusion criteria took first-trimester screening of preeclampsia and SGA. A prior risk based on maternal characteristics was evaluated, and a posterior risk was assessed by combining prior risk with multiple of median (MoM) values of mean arterial pressure (MAP), serum placental growth factor (PLGF) and pregnancy associated plasma protein A (PAPP-A). Both risks were calculated by Preeclampsia PREDICTOR™ software, Perkin Elmer. Screening performance of prior and posterior risks for early and late preeclampsia by using PREDICTOR software was shown by Receiver Operating Characteristics (ROC) curves. The estimation of detection rates and false positive rates of delivery with both preeclampsia and SGA was made.

RESULTS

Eight cases developed early preeclampsia (0.24%) and 35 were diagnosed as late preeclampsia (1.07%). Five with early preeclampsia and ten with late preeclampsia later delivered SGA newborns (0.46%); 84 without preeclampsia gave birth to the SGAs (2.57%). According to ROC curves, posterior risks performed better than prior risks in terms of preeclampsia, especially in early preeclampsia. At 10% false positive rate, detection rates of early and late preeclampsia were 87.50 and 48.57%, detection rates of early and late SGA were 41.67 and 28.00%, respectively. For SGA, detection rates in cases with preeclampsia were much higher than those in absence of it.

CONCLUSIONS

This study demonstrates that combined screening model could be useful for predicting early preeclampsia in Chinese pregnancies. Furthermore, the performance of SGA screening by same protocol is strongly associated with preeclampsia.

Evaluation of fetal medicine foundation algorithm in predicting small-for-gestational-age neonates

OBJECTIVES

To examine the performance of the Fetal Medicine Foundation (FMF) 2012 predictive model and of isolated biophysical markers (uterine artery pulsatility index and mean arterial pressure) for small-for-gestational-age (SGA), in patients from Rio de Janeiro, Brazil.

METHODS

For this cross-sectional study, SGA was diagnosed when a newborn presented birth weight below the fifth percentile for gestational age. FMF2012 algorithm sensitivity and specificity, positive (PPV) and negative (NPV) predictive value, positive likelihood ratio (LR +) and area under the ROC curve (AUC) were calculated to predict total and preterm SGA (SGA < 37). The performance of isolated biophysical markers - mean arterial pressure (MAP) and mean uterine artery pulsatility index (UtAPI) were studied.

RESULTS

The final sample consisted of 1480 cases: 69 (4.6%) developed SGA, including 12 patients (0.8%) who were SGA < 37. The AUC showed that the performances of the FMF2012 combined model for SGA prediction was 0.687 and for preterm SGA was 0.824. With risk cutoff of 1:150, SGA screening yielded the following: sensitivity, 47%; specificity, 75%; LR +, 1.88; PPV, 8.66%; NPV, 96.72%. When screening for preterm SGA, we found sensitivity 66.6%, specificity 74.59%, LR +: 2.58, PPV 2%, and NPV 99.63%.

CONCLUSIONS

Performance of the FMF2012 algorithm in predicting SGA in our population was similar to that obtained in the reference population, according to sensitivity, but our false positive rate is significantly higher than the reference population.

Correlation between uterine artery Doppler and the sFlt-1/PlGF ratio in different phenotypes of placental dysfunction

OBJECTIVE

To explore correlations between the sFlt-1/PlGF ratio and uterine arteries (UtA) Doppler indexes in placental dysfunction-related disorders (PDD).

METHODS

We prospectively included women with a singleton pregnancy with preeclampsia (PE) only (n = 22), preeclampsia with fetal growth restriction (FGR) (n = 32), FGR only (n = 12), or normal pregnancy (n = 29).

RESULTS

In PDDs, significantly positive correlations between the sFlt-1/PlGF ratio and the mean UtA pulsatility (mPI-UtA), as well as the resistance index (mRI-UtA) were found (p = 0.015, p = 0.019, respectively), but not in normal pregnancies. PDD with signs of impaired placentation, evidenced by the increased sFlt-1/PlGF ratio and mPI-UtA, was found in 50.0%, and, by the increased sFlt-1/PlGF ratio and mRI-UtA, in 65.2%. PDD without signs of impaired placentation, evidenced by the increased sFlt-1/PlGF ratio but normal mPI-UtA, was found in 24.2%, and, by the increased sFlt-1/PlGF ratio but normal mRI-UtA, in 7.6%. A substantial proportion of women with signs of impaired placentation were diagnosed with FGR with or without PE.

CONCLUSION

In PDD, the sFlt-1/PlGF ratio and UtA Doppler indexes increase proportionally. Correlations between the sFlt-1/PlGF ratio and UtA Doppler indexes might help to distinguish between PDDs with and without impaired placentation. However, further studies are needed to explore the correlations in different phenotypes of PDD.

Ophthalmic artery Doppler for prediction of pre-eclampsia: systematic review and meta-analysis

OBJECTIVE

To determine the accuracy of ophthalmic artery Doppler in pregnancy for the prediction of pre-eclampsia (PE).

METHODS

MEDLINE, EMBASE, CINAHL and The Cochrane Library were searched for relevant citations without language restrictions. Two reviewers independently selected studies that evaluated the accuracy of ophthalmic artery Doppler to predict the development of PE and extracted data to construct 2 × 2 tables. Individual patient data were obtained from the authors if available. A bivariate random-effects model was used for the quantitative synthesis of data. Logistic regression analysis was employed to generate receiver-operating characteristics (ROC) curves and obtain optimal cut-offs for each investigated parameter, and a bivariate analysis was employed using predetermined cut-offs to obtain sensitivity and specificity values and generate summary ROC curves.

RESULTS

A total of 87 citations matched the search criteria of which three studies, involving 1119 pregnancies, were included in the analysis. All included studies had clear description of the index and reference tests, avoidance of verification bias and adequate follow-up. Individual patient data were obtained for all three included studies. First diastolic peak velocity of ophthalmic artery Doppler at a cut-off of 23.3 cm/s showed modest sensitivity (61.0%; 95% CI, 44.2-76.1%) and specificity (73.2%; 95% CI, 66.9-78.7%) for the prediction of early-onset PE (area under the ROC curve (AUC), 0.68; 95% CI, 0.61-0.76). The first diastolic peak velocity had a much lower sensitivity (39.0%; 95% CI, 20.6-61.0%), a similar specificity (73.2%; 95% CI, 66.9-78.7%) and a lower AUC (0.58; CI, 0.52-0.65) for the prediction of late-onset PE. The pulsatility index of the ophthalmic artery did not show a clinically useful sensitivity or specificity at any cut-off for early- or late-onset PE. Peak ratio above 0.65 showed a similar diagnostic accuracy to that of the first diastolic peak velocity with an AUC of 0.67 (95% CI, 0.58-0.77) for early-onset PE and 0.57 (95% CI, 0.51-0.63) for late-onset disease.

CONCLUSIONS

Ophthalmic artery Doppler is a simple, accurate and objective technique with a standalone predictive value for the development of early-onset PE equivalent to that of uterine artery Doppler evaluation. The relationship between ophthalmic Doppler indices and PE cannot be a consequence of trophoblast invasion and may be related to maternal hemodynamic adaptation to pregnancy. The findings of this review justify efforts to elucidate the effectiveness and underlying mechanism whereby two seemingly unrelated maternal vessels can be used for the prediction of a disease considered a 'placental disorder'. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

sFlt-1/PlGF for prediction of early-onset pre-eclampsia: STEPS (Study of Early Pre-eclampsia in Spain)

OBJECTIVE

A high ratio of soluble fms-like tyrosine kinase-1 (sFlt-1) to placental growth factor (PlGF) has been linked to pre-eclampsia (PE). We evaluated the sFlt-1/PlGF ratio as a predictive marker for early-onset PE in women at risk of PE.

METHODS

This prospective, Spanish, multicenter study included pregnant women with a risk factor for PE, including intrauterine growth restriction, PE, eclampsia or hemolysis, elevated liver enzymes and low platelet count syndrome in previous pregnancy, pregestational diabetes or abnormal uterine artery Doppler. The primary objective was to show that the sFlt-1/PlGF ratio at 20, 24 and 28 weeks' gestation was predictive of early-onset PE (< 34 + 0 weeks). Serum sFlt-1 and PlGF were measured at 20, 24 and 28 weeks. Multivariate logistic regression was used to develop a predictive model.

RESULTS

A total of 819 women were enrolled, of which 729 were suitable for analysis. Of these, 78 (10.7%) women developed PE (24 early onset and 54 late onset). Median sFlt-1/PlGF ratio at 20, 24 and 28 weeks was 6.3 (interquartile range (IQR), 4.1-9.3), 4.0 (IQR, 2.6-6.3) and 3.3 (IQR, 2.0-5.9), respectively, for women who did not develop PE (controls); 14.5 (IQR, 5.5-43.7), 18.4 (IQR, 8.2-57.9) and 51.9 (IQR, 11.5-145.6) for women with early-onset PE; and 6.7 (IQR, 4.6-9.9), 4.7 (IQR, 2.8-7.2) and 6.0 (IQR, 3.8-10.5) for women with late-onset PE. Compared with early-onset PE, the sFlt-1/PlGF ratio was significantly lower in controls (P < 0.001 at each timepoint) and in women with chronic hypertension (P < 0.001 at each timepoint), gestational hypertension (P < 0.001 at each timepoint) and late-onset PE (P < 0.001 at each timepoint). A prediction model for early-onset PE was developed, which included the sFlt-1/PlGF ratio plus mean arterial pressure, being parous and previous PE, with areas under the receiver-operating characteristics curves of 0.86 (95% CI, 0.77-0.95), 0.91 (95% CI, 0.85-0.97) and 0.93 (95% CI, 0.86-0.99) at 20, 24 and 28 weeks, respectively, and was superior to models using the sFlt-1/PlGF ratio alone or uterine artery mean pulsatility index.

CONCLUSIONS

The sFlt-1/PlGF ratio can improve prediction of early-onset PE for women at risk of this condition. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Repeat measurements of uterine artery pulsatility index, mean arterial pressure and serum placental growth factor at 12, 22 and 32 weeks in prediction of pre-eclampsia

OBJECTIVE

To investigate the potential value of repeat measurements of uterine artery pulsatility index (UtA-PI), mean arterial pressure (MAP) and serum placental growth factor (PlGF) at 12, 22 and 32 weeks' gestation in the prediction of pre-eclampsia (PE) developing after 32 weeks.

METHODS

Data were derived from prospective screening for adverse obstetric outcomes in women attending their routine hospital visit at 11-13, 19-24 and/or 30-34 weeks' gestation in two maternity hospitals in England. UtA-PI, MAP and PlGF were measured. Bayes' theorem was used to combine the a-priori risk from maternal factors with UtA-PI, MAP and PlGF multiples of the median values. The performance of screening for PE developing after the 30-34-week visit by UtA-PI, MAP and PlGF measured at 11-13, 19-24 and 30-34 weeks and their combinations was examined.

RESULTS

Screening at 30-34 weeks by UtA-PI, MAP and PlGF detected, at a 10% false-positive rate, 79%, 86% and 92% of preterm PE and 42%, 50% and 56% of term PE. The addition of biomarker values at 11-13 and/or 19-24 weeks was not associated with any improvement in the detection rate of preterm PE; in the case of term PE, there was a marginal (< 2%) improvement in detection for UtA-PI and MAP and a modest improvement of about 5% for PlGF.

CONCLUSION

Measurements of UtA-PI, MAP and PlGF in the first and/or second trimester have a small or no effect on improving the prediction of PE provided by screening in the early third trimester. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Maternal cardiovascular function at 35-37 weeks' gestation: relation to maternal characteristics

OBJECTIVE

To examine the possible effects of maternal characteristics and obstetric and medical history on maternal cardiovascular parameters at 35-37 weeks' gestation.

METHODS

In 3013 singleton pregnancies at 35-37 weeks, maternal characteristics and medical history were recorded; uterine artery pulsatility index, mean arterial pressure (MAP) and maternal cardiovascular parameters were measured. Multivariable regression analysis was used to determine significant predictors of the cardiovascular parameters among gestational age (GA), maternal characteristics and medical history.

RESULTS

Multivariable regression analysis demonstrated that significant independent prediction of log₁₀ cardiac output and log₁₀ cardiac power was provided by GA, maternal age, weight, weight gain from the first trimester, height, racial origin, smoking, assisted conception and previous neonatal birth-weight Z-score in parous women. For log₁₀ total peripheral resistance, significant prediction was provided by GA, maternal age, height, racial origin, chronic hypertension, diabetes mellitus, assisted conception, previous neonatal birth-weight Z-score and prior pre-eclampsia (PE) in parous women. For log₁₀ stroke volume, significant prediction was provided by maternal age, height, racial origin, smoking, chronic hypertension and diabetes mellitus. For heart rate, significant prediction was provided by GA, weight, weight gain, height, racial origin, chronic hypertension, previous neonatal birth-weight Z-score and prior PE in parous women. For log₁₀ MAP, significant prediction was provided by maternal weight, racial origin, family history of PE, chronic hypertension and diabetes mellitus. For log₁₀ thoracic fluid capacity, significant prediction was provided by GA, maternal age, weight, height, racial origin and systemic lupus erythematosus or antiphospholipid syndrome. For log₁₀ ventricular ejection time, significant prediction was provided by GA, weight, height and racial origin.

CONCLUSION

Maternal cardiovascular parameters are affected by maternal characteristics and medical and obstetric history, and they should therefore be converted into multiples of the normal median adjusted for significant independent predictors before their inclusion in combined screening for PE. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Maternal cardiac function at 35-37 weeks' gestation: prediction of pre-eclampsia and gestational hypertension

OBJECTIVE

To investigate the potential value of combining maternal factors with multiples of the normal median values of maternal cardiovascular parameters at 35-37 weeks' gestation in the prediction of pre-eclampsia (PE) and gestational hypertension (GH).

METHODS

In 2764 singleton pregnancies maternal characteristics and medical history were recorded; uterine artery pulsatility index (UtA-PI), mean arterial pressure (MAP) and maternal cardiovascular parameters were measured. Multivariable logistic regression analysis was then used to determine if the maternal factors and maternal cardiovascular parameters made a significant contribution to predicting PE and GH. The performance of screening was determined by the area under receiver-operating characteristics curves.

RESULTS

In pregnancies that subsequently delivered with PE or GH, total peripheral resistance and MAP were higher and maternal cardiac output was lower, mainly owing to a decrease in heart rate in PE and a decrease in stroke volume in GH. The increases in total peripheral resistance and MAP were inversely related to gestational age at delivery. The performance of screening for PE and GH achieved by maternal characteristics and medical history was improved by the inclusion of MAP, but not by UtA-PI or maternal cardiovascular parameters.

CONCLUSIONS

In women developing term PE total peripheral resistance and MAP are increased and maternal cardiac output is reduced. However, assessment of maternal cardiac function at 35-37 weeks' gestation is unlikely to improve the performance of screening for PE provided by maternal factors and MAP alone. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Cardiometabolic Risk and Female Sexuality: Focus on Clitoral Vascular Resistance

INTRODUCTION

The relation between sexual and cardiovascular health in women is not well defined. Clitoral color Doppler ultrasound (CDU) with assessment of the pulsatility index (PI), reflecting resistance to blood flow, has been proposed as an objective measurement of sexual functioning.

AIM

To investigate associations between clitoral PI and cardiometabolic risk factors, sexual and intrapsychic parameters, and self-perception of body image.

METHODS

Seventy-one adult heterosexual women in a stable relationship attending our clinic for sexual dysfunction were consecutively recruited.

MAIN OUTCOME MEASURES

Patients underwent physical, laboratory, and clitoral color Doppler ultrasound examinations and completed the Female Sexual Function Index, the Middlesex Hospital Questionnaire, and the Body Uneasiness Test (BUT).

RESULTS

Clitoral PI was positively correlated with body mass index (r = 0.441, P < .0001), waist circumference (r = 0.474, P < .0001), glycemia (r = 0.300, P = .029), insulin (r = 0.628, P = .002), homeostatic model assessment index (r = 0.605, P = .005), triglycerides (r = 0.340, P = .011), total cholesterol (r = 0.346, P = .010), and low-density lipoprotein cholesterol (r = 0.334, P = .016). All relations, with the exception of glycemia, retained statistical significance after adjusting for age, smoking habit, and years since menopause (P < .0001 for body mass index, waist circumference, and triglycerides; P < .05 for all other associations). Analysis of covariance, after adjusting for confounders, showed that women with obesity or metabolic syndrome (MetS) showed significantly higher PI values (obesity: F = 17.79, P = .001; MetS: F = 7.37, P = .019). In particular, a stepwise increase of PI was found as a function of increasing MetS components (β = 0.434, P = .007). Clitoral PI was negatively associated with Female Sexual Function Index arousal (β = -0.321, P = .014) and satisfaction (β = -0.289, P = .026) scores and positively associated with Middlesex Hospital Questionnaire somatized anxiety symptoms, even after adjusting for age, smoking habit, years since menopause, and current use of psychiatric medication (β = 0.354, P = .011). A positive association also was observed between PI and the BUT positive symptom distress index (β = 0.322, P = .039) and BUT for dislike of the womb, genitals, and breast (β = 0.538, P < .0001; β = 0.642, P < .0001; β = 0.549, P < .0001, respectively). After introducing waist circumference as another covariate, the associations between clitoral PI and the BUT positive symptom distress index and BUT dislike of the womb, genitals, and breast retained statistical significance (P = .038 for positive symptom distress index; P < .0001 for dislike of womb, genitals, and breast).

CONCLUSION

Clitoral vascular resistance is positively associated with MetS (in particular insulin resistance), decreased sexual arousal, body image concerns, and increased somatized anxiety symptoms. Further studies are needed to establish whether treatment of metabolic abnormalities might improve clitoral color Doppler ultrasound indices and sexual outcomes.