Clinical phenotypes for risk stratification in small-for-gestational-age fetuses.

OBJECTIVE: To evaluate whether clinical phenotypes of small-for-gestational-age (SGA) fetuses can be identified and used for adverse perinatal outcome risk stratification to facilitate clinical decision-making. METHODS: This was a multicenter observational cohort study conducted in two tertiary care university hospitals. SGA fetuses were classified according to maternal, fetal and placental conditions using a two-step cluster algorithm, in which fetuses with more than one condition were assigned to the cluster associated with the highest mortality risk. Delivery and perinatal outcomes were compared using chi-square test among SGA clusters, and the associations between outcomes and each cluster were evaluated by calculating odds ratios (OR), adjusted for gestational age. RESULTS: The study included 17 631 consecutive singleton pregnancies, of which 1274 (7.2%) were defined as SGA at birth according to INTERGROWTH-21st standards. Nine SGA clinical phenotypes were identified using a predefined conceptual framework. All delivery and perinatal outcomes analyzed were significantly different among the nine phenotypes. The whole SGA cohort had a three-times higher risk of perinatal mortality compared with non-SGA fetuses (1.4% vs 0.4%; P < 0.001). SGA clinical phenotypes exhibited three patterns of perinatal mortality risk: the highest risk was associated with congenital anomaly (8.3%; OR, 17.17 (95% CI, 2.17-136.12)) and second- or third-trimester hemorrhage (8.3%; OR, 9.94 (95% CI, 1.23-80.02)) clusters; medium risk was associated with gestational diabetes (3.8%; OR, 9.59 (95% CI, 1.27-72.57)), preterm birth (3.2%; OR, 4.65 (95% CI, 0.62-35.01)) and intrauterine growth restriction (3.1%; OR, 5.93 (95% CI, 3.21-10.95)) clusters; and the lowest risk was associated with the remaining clusters. Perinatal mortality rate did not differ between SGA fetuses without other clinical conditions (54.1% of SGA fetuses) and appropriate-for-gestational-age fetuses (0.1% vs 0.4%; OR, 0.41 (95% CI, 0.06-2.94); P = 0.27). SGA combined with other obstetric pathologies increased significantly the risk of perinatal mortality, as demonstrated by the increased odds of perinatal death in SGA cases with gestational diabetes compared to non-SGA cases with the same condition (OR, 24.40 (95% CI, 1.31-453.91)). CONCLUSIONS: We identified nine SGA clinical phenotypes associated with different patterns of risk for adverse perinatal outcome. Our findings suggest that considering clinical characteristics in addition to ultrasound findings could improve risk stratification and decision-making for management of SGA fetuses. Future clinical trials investigating management of fetuses with SGA should take into account clinical information in addition to Doppler parameters and estimated fetal weight. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

SARS-CoV-2 immunochromatographic IgM/IgG rapid test in pregnancy: A false friend?

BACKGROUND: An increasing body of evidence has revealed that SARS-CoV-2 infection in pregnant women could increase the risk of adverse maternal and fetal outcomes. Careful monitoring of pregnancies with COVID-19 and measures to prevent neonatal infection are warranted. Therefore, rapid antibody tests have been suggested as an efficient screening tool during pregnancy. CASES: We analysed the clinical performance during pregnancy of a rapid, lateral-flow immunochromatographic assay for qualitative detection of SARS-CoV-2 IgG/IgM antibodies. We performed a universal screening including 169 patients during their last trimester of pregnancy. We present a series of 14 patients with positive SARS-CoV-2 immunochromatographic assay rapid test result. Immunochromatographic assay results were always confirmed by chemiluminescent microparticle immunoassays for quantitative detection of SARS-CoV-2 IgG and IgM+IgA antibodies as the gold standard. We observed a positive predictive value of 50% and a false positive rate of 50% in pregnant women, involving a significantly lower diagnostic performance than reported in non-pregnant patients. DISCUSSION: Our data suggest that although immunochromatographic assay rapid tests may be a fast and profitable screening tool for SARS-CoV-2 infection, they may have a high false positive rate and low positive predictive value in pregnant women. Therefore, immunochromatographic assay for qualitative detection of SARS-CoV-2 IgG/IgM antibodies must be verified by other test in pregnant patients.

Quality assessment of fetal middle cerebral and umbilical artery Doppler images using an objective scale within an international randomized controlled trial.

OBJECTIVES: To determine the quality of Doppler images of the fetal middle cerebral artery (MCA) and umbilical artery (UA) using an objective scale, and to determine the reliability of this scale, within a multicenter randomized controlled trial (Revealed versus concealed criteria for placental insufficiency in unselected obstetric population in late pregnancy (Ratio37)). METHODS: The Ratio37 trial is an ongoing randomized, open-label, multicenter controlled study of women with a low-risk pregnancy recruited at 20 weeks. Doppler measurements of the fetal MCA and UA were performed at 37 weeks. Twenty patients from each of the six participating centers were selected randomly, with two images evaluated per patient (one each for the MCA and UA). The quality of a total of 240 images was evaluated by six experts, scored on an objective scale of six items. Inter- and intrarater reliability was assessed using the Fleiss-modified kappa statistic for ordinal scales. RESULTS: On average, 89.2% of MCA images and 85.0% of UA images were rated as being of perfect (score of 6) or almost perfect (score of 5) quality. Kappa values for intrarater reliability of quality assessment were 0.90 (95% CI, 0.88-0.92) and 0.90 (95% CI, 0.88-0.93) for the MCA and UA, respectively. The corresponding inter-rater reliability values were 0.85 (95% CI, 0.81-0.89) and 0.84 (95% CI, 0.80-0.89), respectively. CONCLUSION: The quality of MCA and UA Doppler ultrasound images can be evaluated reliably using an objective scale. Over 85% of images, which were obtained by operators from a broad range of clinical practices within a multicenter study, were rated as being of perfect or almost perfect quality. Intra- and inter-rater reliability of quality assessment was very good. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Clinical impact of Doppler reference charts on management of small-for-gestational-age fetuses: need for standardization.

OBJECTIVE: To assess clinical variability in the management of small-for-gestational-age (SGA) fetuses according to different published Doppler reference charts for umbilical artery (UA) and fetal middle cerebral artery (MCA) Doppler indices and cerebroplacental ratio (CPR). METHODS: We performed a systematic search of MEDLINE, EMBASE, CINAHL and the Web of Science databases from 1954 to 2018 for studies with the sole aim of creating fetal Doppler reference values for UA, MCA and CPR. The top cited articles for each Doppler parameter were included. Variability in Doppler values at the following clinically relevant cut-offs was assessed: UA-pulsatility index (PI) > 95th percentile; MCA-PI < 5th percentile; and CPR < 5th percentile. Variability was calculated for each week of gestation and expressed as the percentage difference between the highest and lowest Doppler value at the clinically relevant cut-offs. Simulation analysis was performed in a cohort of SGA fetuses (n = 617) to evaluate the impact of this variability on clinical management. RESULTS: From a total of 40 studies that met the inclusion criteria, 19 were analyzed (13 for UA-PI, 10 for MCA-PI and five for CPR). Wide discrepancies in reported Doppler reference values at clinically relevant cut-offs were found. MCA-PI showed the greatest variability, with differences of up to 51% in the 5th percentile value at term. Variability in the 95th percentile of UA-PI and the 5th percentile of CPR at each gestational week ranged from 21% to 41% and 15% to 33%, respectively. As expected, on simulation analysis, these differences in Doppler cut-off values were associated with significant variation in the clinical management of SGA fetuses, despite using the same protocol. CONCLUSIONS: The choice of Doppler reference chart can result in significant variation in the clinical management of SGA fetuses, which may lead to suboptimal outcomes and inaccurate research conclusions. Therefore, an attempt to standardize fetal Doppler reference ranges is needed. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Reference ranges for Doppler indices of umbilical and fetal middle cerebral arteries and cerebroplacental ratio: systematic review.

OBJECTIVE: To assess studies reporting reference ranges for umbilical artery (UA) and fetal middle cerebral artery (MCA) Doppler indices and cerebroplacental ratio (CPR), using a set of predefined methodological quality criteria for study design, statistical analysis and reporting methods. METHODS: This was a systematic review of observational studies in which the primary aim was to create reference ranges for UA and MCA Doppler indices and CPR in fetuses of singleton gestations. A search for relevant articles was performed in MEDLINE, EMBASE, CINAHL, Web of Science (from inception to 31 December 2016) and references of the retrieved articles. Two authors independently selected studies, assessed the risk of bias and extracted the data. Studies were scored against a predefined set of independently agreed methodological criteria and an overall quality score was assigned to each study. Linear multiple regression analysis assessing the association between quality scores and study characteristics was performed. RESULTS: Thirty-eight studies met the inclusion criteria. The highest potential for bias was noted in the following fields: 'ultrasound quality control measures', in which only two studies demonstrated a comprehensive quality-control strategy; 'number of measurements taken for each Doppler variable', which was apparent in only three studies; 'sonographer experience', in which no study on CPR reported clearly the experience or training of the sonographers, while only three studies on UA Doppler and four on MCA Doppler did; and 'blinding of measurements', in which only one study, on UA Doppler, reported that sonographers were blinded to the measurement recorded during the examination. Sample size estimations were present in only seven studies. No predictors of quality were found on multiple regression analysis. Reference ranges varied significantly with important clinical implications for what is considered normal or abnormal, even when restricting the analysis to the highest scoring studies. CONCLUSIONS: There is considerable methodological heterogeneity in studies reporting reference ranges for UA and MCA Doppler indices and CPR, and the resulting references have important implications for clinical practice. There is a need for the standardization of methodologies for Doppler velocimetry and for the development of reference standards, which can be correctly interpreted and applied in clinical practice. We propose a set of recommendations for this purpose. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Intervalos de referencia para los índices Doppler de la arterias umbilical y cerebral media del feto y la relación cerebroplacentaria: una revisión sistemática OBJETIVO: Evaluar los estudios que informan sobre intervalos de referencia para los índices Doppler y la relación cerebroplacentaria (RCP) de la arteria umbilical (AU) y la arteria cerebral media (ACM) del feto, mediante un conjunto de criterios de calidad metodológica predefinidos para el diseño del estudio, el análisis estadístico y los métodos de notificación. MÉTODOS: Esta fue una revisión sistemática de estudios observacionales en los que el objetivo principal fue crear intervalos de referencia para los índices Doppler de la AU y la ACM y la RCP de fetos de gestaciones con feto único. Se realizó una búsqueda de artículos relevantes en MEDLINE, EMBASE, CINAHL, Web of Science (desde el inicio hasta el 31 de diciembre de 2016) y en las referencias de los artículos recuperados. Dos autores, de forma independiente, seleccionaron los estudios, evaluaron el riesgo de sesgo y extrajeron los datos. Los estudios se calificaron según un conjunto predefinido de criterios metodológicos acordados de forma independiente y se asignó una puntuación de calidad global a cada estudio. Se realizó un análisis de regresión múltiple lineal para evaluar la asociación entre las puntuaciones de calidad y las características del estudio. RESULTADOS: Un total de 38 estudios cumplieron los criterios de inclusión. El mayor potencial de sesgo se observó en los siguientes casos: 'medidas de control de calidad del ultrasonido', donde sólo dos estudios demostraron una estrategia integral de control de calidad; 'número de mediciones tomadas para cada variable Doppler', que solo fue aparente en tres estudios; 'experiencia del ecografista', puesto que ningún estudio sobre la RCP informó claramente sobre la experiencia o la formación de los ecografistas, y tan solo lo hicieron tres estudios sobre el Doppler de la AU y cuatro sobre el Doppler de la ACM; y 'mediciones a ciegas', donde tan sólo un estudio sobre el Doppler de la AU comunicó que los ecografistas no tuvieron acceso a la medición registrada durante el estudio. Las estimaciones del tamaño de la muestra sólo se comunicaron en siete estudios. No se encontraron predictores de calidad en el análisis de regresión múltiple. Los intervalos de referencia variaron significativamente con implicaciones clínicas importantes para lo que se considera normal o anómalo, incluso cuando se restringió el análisis a los estudios con mayor puntuación. CONCLUSIONES: Existe una heterogeneidad metodológica considerable en los estudios que informan sobre los intervalos de referencia para los índices Doppler de la AU y la ACM y la RCP, y las referencias resultantes tienen implicaciones importantes para la práctica clínica. Es necesario estandarizar las metodologías de la velocimetría Doppler y desarrollar estándares de referencia que puedan ser interpretados y aplicados correctamente en la práctica clínica. Se propone una serie de recomendaciones para este fin.

Altered gene expression in human placenta after suspected preterm labour.

INTRODUCTION: Suspected preterm labour occurs in around 9% of pregnancies. However, almost two-thirds of women admitted for threatened preterm labour ultimately deliver at term and are considered risk-free for fetal development. METHODS: We examined placental and umbilical cord blood samples from preterm or term deliveries after threatened preterm labour as well as term deliveries without threatened preterm labour. We quantitatively analysed the mRNA expression of inflammatory markers (IL6, IFNγ, and TNFα) and modulators of angiogenesis (FGF2, PGF, VEGFA, VEGFB, and VEGFR1). RESULTS: A total of 132 deliveries were analysed. Preterm delivery and term delivery after suspected preterm labour groups showed similar increases in TNFα expression compared with the term delivery control group in umbilical cord blood samples. Placental samples from preterm and term deliveries after suspected preterm labour exhibited significantly increased expression of TNFα and IL6 and decreased expression of IFNγ. Suspected preterm labour was also associated with altered expression of angiogenic factors, although not all differences reached statistical significance. DISCUSSION: We found gene expression patterns indicative of inflammation in human placentas after suspected preterm labour regardless of whether the deliveries occurred preterm or at term. Similarly, a trend towards altered expression of angiogeneic factors was not limited to preterm birth. These findings suggest that the biological mechanisms underlying threatened preterm labour affect pregnancies independently of gestational age at birth.

Impact of aspirin on trophoblastic invasion in women with abnormal uterine artery Doppler at 11-14 weeks: a randomized controlled study.

OBJECTIVE: Defective trophoblastic invasion is a key feature in many cases of pre-eclampsia (PE). Uterine artery (UtA) Doppler is a validated non-invasive proxy for trophoblastic invasion. The aim of this study was to explore whether low-dose aspirin, administered from the first trimester, improves trophoblastic invasion, evaluated by UtA Doppler during the second and third trimesters in women defined as high risk by abnormal first-trimester UtA Doppler. METHODS: This randomized Phase-II study had a triple-blind, parallel-arm, controlled design. Singleton pregnancies with abnormal mean UtA Doppler at 11-14 weeks and absence of other major risk factors for PE received 150 mg extended-release aspirin or identical-appearing placebo tablets from study inclusion to 28 weeks. Main outcome measure was UtA pulsatility index (PI) at 28 weeks' gestation. Secondary outcomes included frequency of development of PE and growth restriction/small-for-gestational age (SGA). RESULTS: A total of 155 women completed the follow-up and were analyzed. No difference in mean UtA-PI was found between women in the aspirin and placebo groups at 28 weeks (mean UtA-PI Z-score (mean ± SD), 0.99 ± 1.48 vs 0.85 ± 1.25; P = 0.52). Seven women developed PE: four (5%) in the aspirin group and three (4%) in the placebo group. There was a trend toward lower incidence of SGA in the aspirin group (8.8% vs 17.3%; P = 0.11). CONCLUSION: In women with defective trophoblastic invasion, as reflected by abnormal UtA Doppler, low-dose aspirin started in the first trimester does not have a significant effect on UtA impedance as pregnancy progresses; however, the study was underpowered to detect potential small effects . Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Vaginal progesterone as maintenance treatment after an episode of preterm labour (PROMISE) study: a multicentre, double-blind, randomised, placebo-controlled trial.

OBJECTIVE: To evaluate whether maintenance treatment with vaginal progesterone after an arrested preterm labour reduces the incidence of preterm delivery. DESIGN: Multicentre, randomised, double-blind, placebo-controlled trial. SETTING: Twelve tertiary care centres in Spain. POPULATION: A total of 265 women with singleton pregnancy, preterm labour successfully arrested with tocolytic treatment, and cervical length of <25 mm. METHODS: Randomisation was stratified by gestational age (from 24.0 to <31.0 weeks of gestation and from 31.0 to <34.0 weeks of gestation) and centre. Patients were randomly assigned, in a 1 : 1 ratio, to either daily vaginal capsules of 200 mg progesterone or placebo until delivery or 36.6 weeks of gestation, whichever occurred first. MAIN OUTCOME MEASURES: Primary outcome was delivery before 34.0 and 37.0 weeks of gestation. Secondary outcomes were discharge-to-delivery time, readmissions because of preterm labour, emergency service use, and neonatal morbidity and mortality. RESULTS: From June 2008 through June 2012, 1419 women were screened: 472 met the inclusion criteria and 265 were randomised. The final analysis included 258 women: 126 in the progesterone group and 132 in the placebo group. There were no significant differences between the progesterone and placebo groups in terms of delivery at <34 weeks of gestation [9/126 (7.1%) versus 10/132 (7.6%), P = 0.91] or <37 weeks of gestation [36/126 (28.6%) versus 29/132 (22.0%), P = 0.22]. There were no differences observed between groups when considering the two strata of gestational age at inclusion. CONCLUSIONS: A maintenance treatment of 200 mg of daily vaginal progesterone capsules in women discharged home after an episode of arrested preterm labour did not significantly reduce the rate of preterm delivery. TWEETABLE ABSTRACT: Maintenance progesterone in 258 women after arrested PTL showed no benefit.

Cervical condition and fetal cerebral Doppler as determinants of adverse perinatal outcome after labor induction for late-onset small-for-gestational-age fetuses.

OBJECTIVE: To estimate the combined value of fetal cerebral Doppler examination and Bishop score for predicting perinatal outcome after labor induction for small-for-gestational-age (SGA) fetuses in the presence of normal umbilical artery Doppler recordings. METHODS: We conducted a cohort study in two tertiary centers, including 164 women with normal umbilical artery Doppler recordings who underwent induction of labor because of an estimated fetal weight < 10(th) percentile. The fetal middle cerebral artery pulsatility index and cerebroplacental ratio (CPR) were obtained in all cases within 24 h before induction. Cervical condition was assessed at admission using the Bishop score. A predictive model for perinatal outcomes was constructed using a decision-tree analysis algorithm. RESULTS: Both a very unfavorable cervix, defined as a Bishop score < 2, (odds ratio (OR), 3.18; 95% CI, 1.28-7.86) and an abnormal CPR (OR, 2.54; 95% CI, 1.18-5.61) were associated with an increased likelihood of emergency Cesarean section for fetal distress, but only the latter was significantly associated with the need for neonatal admission (OR, 2.43; 95% CI, 1.28-4.59). In the decision-tree analysis, both criteria significantly predicted the likelihood of Cesarean section for fetal distress. CONCLUSION: Combined use of the Bishop score and CPR improves the ability to predict overall Cesarean section (for any indication), emergency Cesarean section for fetal distress, and neonatal admission after labor induction for late-onset SGA in the presence of normal umbilical artery Doppler recordings.

Pathways of neuronal and cognitive development in children born small-for-gestational age or late preterm.

OBJECTIVE: To assess the effects of late small-for-gestational-age (SGA) birth and late prematurity on cognitive outcomes and structural changes in the central nervous system at primary school age, using a novel approach to examine changes in neuronal integrity of the retina. METHODS: We conducted a cross-sectional study of 347 children aged 6-13 years, including in the analysis only infants born after 34 weeks' gestation. We recorded all perinatal outcomes through a survey of parents. Neuronal damage was evaluated using optical coherence tomography of the retina. In a subgroup of 112 children aged 6-8 years, visuospatial perception was evaluated with the Children's Bender Visual Motor Gestalt Test. RESULTS: The proportions of SGA and late preterm children were 11.8 and 6.3%, respectively. Prematurity and SGA were simultaneously present in five children. When compared with controls, SGA children showed significantly lower than average retinal nerve fiber layer (RNFL) thickness (94.1 vs 98.8 µm; P = 0.007) and an increased percentage of abnormal Bender scores (27.3 vs 6.2%; P = 0.017) (odds ratio 5.6 (95% CI, 1.2-26.8)). These differences increased when late SGA infants with a birth weight below the 3(rd) percentile were compared with SGA infants with a birth weight between the 3(rd) and 10(th) percentiles and with controls, for RNFL thickness (92.5 vs 94.6 and 98.8 µm, respectively; P = 0.021) and abnormal Bender tests (33.3 vs 25.0 and 6.2%, respectively; P = 0.036). However, no differences were found in retinal structure and visuomotor performance between late preterm and term infants. CONCLUSIONS: These data suggest that late SGA and late prematurity induce a distinct neuronal pattern of structural changes that persist at school age. Late-onset SGA infants are at increased risk for axonal loss in the retina and present specific visuomotor difficulties.

Axonal loss and cognitive deficits in term infants with normal umbilical artery Doppler born small-for-gestational age.

OBJECTIVE: To assess cognitive outcomes and structural changes in the central nervous system, the latter using a novel approach to examine changes in neuronal integrity of the optic nerve, in children at 5-6½ years of age who were born small-for-gestational age (SGA) at term having shown normal umbilical artery (UA) Doppler. METHODS: We compared neuronal damage, cognitive deficits and visuospatial perception in two cohorts of infants, one born SGA (n = 40) and one born appropriate-for-gestational age (AGA) (n = 39) in weight. Neuronal damage was evaluated using optical coherence tomography (OCT) of the optic nerve. Cognitive deficits were assessed with the Wechsler Preschool and Primary Scale of Intelligence (WPPSI) test. Visuospatial perception was evaluated with Rey-Osterreich Complex Figure (ROCF) tasks. RESULTS: Children from the SGA group had a significantly thinner average retinal nerve fiber layer (RNFL) compared with those from the AGA group (98.2 vs 104.5 µm, P = 0.012). Children from the SGA group exhibited impaired performance in copy tasks on the ROCF (3.27 vs 3.56, P = 0.036) and a higher rate of suboptimal WPPSI test performance intelligence quotient scores (15% vs 0%; P = 0.025) compared with those from the AGA group. CONCLUSION: Term infants with normal UA Doppler born SGA are at increased risk for cognitive deficits and axonal loss in the RNFL at the age of 5-6½ years.

Changes in myocardial performance index and aortic isthmus and ductus venosus Doppler in term, small-for-gestational age fetuses with normal umbilical artery pulsatility index.

OBJECTIVE: To evaluate the changes in myocardial performance index (MPI) and aortic isthmus (AoI) and ductus venosus (DV) Doppler in term, small-for-gestational age (SGA) fetuses with normal umbilical artery (UA) Doppler. METHODS: MPI, AoI and DV pulsatility indices (PI) were measured within 1 week prior to delivery in a cohort of 178 term singleton consecutive SGA fetuses with normal UA-PI (< 95(th) percentile) and 178 controls matched by gestational age. Cardiovascular parameters were converted into Z-scores and values above the 95(th) centile defined as abnormal. RESULTS: Median gestational age at inclusion and at delivery was 35.7 and 38.6 weeks, respectively. Compared to controls, SGA fetuses showed significantly higher values in MPI and AoI-PI and similar values in DV-PI. SGA fetuses showed a significantly higher proportion of increased MPI (28.1 vs. 6.7%; P < 0.01) and abnormal AoI-PI (14.6 vs. 5.1%; P < 0.01) than controls. The proportion of cases with abnormal DV-PI was similar between SGA cases and controls. Retrograde net blood flow in the AoI was observed in 7.3% of the SGA cases and in none of the controls. CONCLUSION: A proportion of SGA fetuses show cardiovascular Doppler abnormalities. This information might be of clinical relevance in improving the detection and management of late-onset intrauterine growth restriction.

Longitudinal changes in uterine, umbilical and fetal cerebral Doppler indices in late-onset small-for-gestational age fetuses.

OBJECTIVES: To determine the longitudinal trends and rates of conversion of normal to abnormal uterine (UtA), umbilical (UA) and middle cerebral artery (MCA) Doppler velocimetry throughout the third trimester in late-onset small-for-gestational-age (SGA) fetuses. METHODS: UtA, UA and MCA Doppler velocimetry was serially performed in a cohort of singleton consecutive late-onset SGA fetuses with normal Doppler values at diagnosis. The rate of conversion of normal to abnormal Doppler values was evaluated by survival analysis. Longitudinal trends were modeled by means of multilevel analysis. RESULTS: A total of 616 scans were performed on 171 SGA fetuses. Mean gestational age at inclusion and at delivery was 34.1 (SD 1.6) and 38.7 (SD 1.7) weeks, respectively. The proportions of abnormal UtA (2.3 vs. 4.1%) and UA (2.3 vs. 2.9%) pulsatility index (PI) were not significantly different between 37 weeks and before delivery. On the other hand, the proportions of abnormal MCA-PI (4.1 vs. 13.5%) and cerebroplacental ratio (CPR) (7 vs. 22.8%) were significantly different between these two examinations. The remaining proportion of cases with normal UtA-, UA- and MCA-PIs and CPR at 40 weeks were 98.6, 94.5, 85 and 49.6%, respectively. Whereas a slight increasing trend was observed for the UtA-PI (ß = 0.002) and UA-PI (ß = 0.01), MCA-PI (ß = 0.044) and CPR (ß = 0.124) showed a progressive decrease until delivery. CONCLUSIONS: Late-onset SGA fetuses with normal Doppler velocimetry upon diagnosis show progression from 37 weeks' gestation with worsening CPR followed by a decrease in MCA-PI.

Middle versus anterior cerebral artery Doppler for the prediction of perinatal outcome and neonatal neurobehavior in term small-for-gestational-age fetuses with normal umbilical artery Doppler.

OBJECTIVE: To evaluate whether anterior cerebral artery (ACA) Doppler ultrasonography is superior to middle cerebral artery (MCA) Doppler in the prediction of perinatal outcome and neonatal neurobehavior in term small-for-gestational-age (SGA) fetuses with normal umbilical artery (UA) Doppler. METHODS: MCA and ACA Doppler ultrasonography was performed in a cohort of SGA term fetuses with normal UA Doppler. Perinatal outcome and neonatal neurobehavioral performance were compared with a group of term appropriate-for-gestational age (AGA) infants. Neurobehavior was evaluated at 40 ( +/- 1) weeks of corrected age with the Neonatal Behavioral Assessment Scale. Differences between the study groups were adjusted for potential confounding variables by multiple linear or logistic regression analyis. RESULTS: A total of 199 newborns (98 SGA and 101 AGA) were included. Among the SGA fetuses, 28.6 and 17% had MCA and ACA redistribution, respectively. Cases with either type of redistribution had an increased risk for adverse outcome, with no differences in predictive performance between the two parameters. SGA fetuses with MCA redistribution compared with controls had an increased risk for abnormal neurobehavioral performance in motor (36 vs. 20%; adjusted P = 0.02) and state organization (25 vs. 17.5%; adjusted P = 0.03) areas. SGA fetuses with ACA redistribution had only an increased risk for abnormal neurobehavioral performance area in state organization compared with controls (30 vs. 17.5%; adjusted P = 0.021). CONCLUSION: In term SGA newborns with no signs of brain-sparing, ACA Doppler investigation does not provide any benefit over MCA in terms of the prediction of adverse perinatal outcome.

Reference values for Doppler parameters of the fetal anterior cerebral artery throughout gestation.

AIM: To construct normal reference values for Doppler parameters in 2 anatomical segments of the fetal anterior cerebral artery (ACA) throughout pregnancy. METHODS: The ACA was evaluated in 373 normally growing fetuses from 20 to 40 weeks of gestation. The first segment of the ACA (ACA-S1) was recorded just after its origin from the internal carotid artery in the same plane as the middle cerebral artery (MCA). The second segment (ACA-S2) was recorded distal to the outlet of the anterior communicating artery. RESULTS: The ACA pulsatility index (PI) behaved similarly in both segments, with a constant increase until 28 weeks followed by a decrease until the end of pregnancy [ACA-S1 PI = 3.49 - 0.37 x gestational age (GA) - (0.0063 x GA(2)), SD = 0.6 - 0.061 x GA - (0.001 x GA(2)); ACA-S2 PI = 1.54 - 0.22 x GA - (0.0037 x GA(2)), SD = 0.206 + (0.0037 x GA)]. Peak systolic velocities in both segments showed a constant increase from 20 to 40 weeks of gestation. No significant differences were found between the 2 segments with regard to any Doppler parameter. However, the angle of insonation and the time spent on examination were significantly lower and reproducibility was better for ACA-S1. CONCLUSION: Despite showing similar Doppler values, ACA-S1 has a higher reliability than ACA-S2 and can be recorded in the same anatomical projection as the MCA.