The fetus develops normally in a hypoxic environment but exaggerated hypoxia late in pregnancy is a worrisome sign often observed in hypertensive disorders of pregnancy, placental insufficiency, or fetal growth restriction (FGR). Serial fetal biometry and the cerebroplacental ratio (CPR, calculated as the middle cerebral artery [MCA] / the umbilical artery [UmbA] pulsatility indices [PI]), are commonly used to indicate fetal "brain sparing" resulting from exaggerated fetal hypoxia. But unclear is the extent to which a low CPR indicates pathology or is a physiological response for maintaining cerebral blood flow. We studied 31 appropriate for gestational age (AGA) pregnancies at low (LA, 1670 m) or high (HA, 2879 m) altitude, given the chronic hypoxia imposed by HA residence, and 54 LA women with a clinical diagnosis of FGR. At week 34, the MCA PI was lower in the LA-FGR than the LA-AGA group but lower still in the HA-AGA compared to either LA groups due to a trend toward higher end-diastolic velocity (EDV). We concluded that the lower MCA PI was likely due to greater cerebral vasodilation in the HA AGA group and an indication of physiological versus pathological fetal hypoxia. Future reporting of serial MCA and UmbA values and their determinants along with the CPR could improve our ability to distinguish between physiological and pathological fetal brain sparing. Keywords: Birth weight, Cerebroplacental ratio, Fetal physiology, HDP, High altitude.

• MeSH
• arteria cerebri media * diagnostické zobrazování   patofyziologie   MeSH
• arteriae umbilicales diagnostické zobrazování   patofyziologie   MeSH
• dospělí MeSH
• hypoxie plodu * patofyziologie   MeSH
• hypoxie patofyziologie   MeSH
• lidé MeSH
• mozek patofyziologie   krevní zásobení   diagnostické zobrazování   MeSH
• mozkový krevní oběh fyziologie   MeSH
• nadmořská výška MeSH
• růstová retardace plodu * patofyziologie   MeSH
• těhotenství MeSH
• ultrasonografie prenatální metody   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

PURPOSE: To assess the longitudinal variation of the ratio of umbilical and cerebral artery pulsatility index (UCR) in late preterm fetal growth restriction (FGR). MATERIALS AND METHODS: A prospective European multicenter observational study included women with a singleton pregnancy, 32+ 0-36+ 6, at risk of FGR (estimated fetal weight [EFW] or abdominal circumference [AC] < 10th percentile, abnormal arterial Doppler or fall in AC from 20-week scan of > 40 percentile points). The primary outcome was a composite of abnormal condition at birth or major neonatal morbidity. UCR was categorized as normal (< 0.9) or abnormal (≥ 0.9). UCR was assessed by gestational age at measurement interval to delivery, and by individual linear regression coefficient in women with two or more measurements. RESULTS: 856 women had 2770 measurements; 696 (81 %) had more than one measurement (median 3 (IQR 2-4). At inclusion, 63 (7 %) a UCR ≥ 0.9. These delivered earlier and had a lower birth weight and higher incidence of adverse outcome (30 % vs. 9 %, relative risk 3.2; 95 %CI 2.1-5.0) than women with a normal UCR at inclusion. Repeated measurements after an abnormal UCR at inclusion were abnormal again in 67 % (95 %CI 55-80), but after a normal UCR the chance of finding an abnormal UCR was 6 % (95 %CI 5-7 %). The risk of composite adverse outcome was similar using the first or subsequent UCR values. CONCLUSION: An abnormal UCR is likely to be abnormal again at a later measurement, while after a normal UCR the chance of an abnormal UCR is 5-7 % when repeated weekly. Repeated measurements do not predict outcome better than the first measurement, most likely due to the most compromised fetuses being delivered after an abnormal UCR.

• MeSH
• arteriae umbilicales diagnostické zobrazování   MeSH
• gestační stáří MeSH
• hmotnost plodu MeSH
• hypotrofický novorozenec MeSH
• lidé MeSH
• novorozenec MeSH
• předčasný porod * MeSH
• prospektivní studie MeSH
• růstová retardace plodu * MeSH
• těhotenství MeSH
• ultrasonografie dopplerovská MeSH
• ultrasonografie prenatální MeSH
• Check Tag
• lidé MeSH
• novorozenec MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• pozorovací studie MeSH

INTRODUCTION: This study aimed to determine the effect and clinical impact of physiological characteristics on the 95th/5th centile of the umbilical artery (UA) Doppler and the cerebroplacental ratio (CPR), at 36+ weeks. METHODS: From the multicenter randomized trial "Ratio37," we selected 4,505 low-risk pregnant women between June 2016 and January 2020. We registered physiological characteristics and the pulsatility indexes (PI) of the UA and middle cerebral artery (36-39 weeks). The 95th/5th centile of the UA PI and CPR was modeled by quantile regression. To evaluate the clinical impact of adjusting Doppler, we retrospectively applied gestational age (GA) and fully adjusted standards to 682 small for gestational age (SGA)-suspected fetuses (37 weeks) from a cohort of consecutive patients obtained between January 2010 and January 2020. RESULTS: Several physiological characteristics significantly influenced the 95th/5th centile of the UA and CPR PI. The fully adjusted 95th centile of the UA was higher, and the 5th centile of the CPR was lower than GA-only-adjusted standards. Of the 682 SGA fetuses, 150 (22%) were classified as late fetal growth restricted only by GA and 112 (16.4%) when we adjusted Doppler. These 38 fetuses had similar perinatal outcome than the SGA group. DISCUSSION: The 95th/5th centile of the UA and CPR PI is significantly influenced by physiological characteristics. Adjusting Doppler standards could differentiate better between FGR and SGA.

• MeSH
• arteria cerebri media diagnostické zobrazování   MeSH
• arteriae umbilicales diagnostické zobrazování   MeSH
• gestační stáří MeSH
• hypotrofický novorozenec MeSH
• lidé MeSH
• novorozenec MeSH
• placenta * diagnostické zobrazování   MeSH
• plod MeSH
• pulzatilní průtok MeSH
• retrospektivní studie MeSH
• růstová retardace plodu * diagnostické zobrazování   MeSH
• těhotenství MeSH
• ultrasonografie dopplerovská MeSH
• ultrasonografie prenatální MeSH
• Check Tag
• lidé MeSH
• novorozenec MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• randomizované kontrolované studie MeSH

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.

• MeSH
• arteria cerebri media diagnostické zobrazování   embryologie   MeSH
• arteriae umbilicales diagnostické zobrazování   embryologie   MeSH
• dospělí MeSH
• lidé MeSH
• plod krevní zásobení   diagnostické zobrazování   embryologie   MeSH
• randomizované kontrolované studie jako téma MeSH
• reprodukovatelnost výsledků MeSH
• ultrasonografie dopplerovská normy   MeSH
• ultrasonografie prenatální normy   MeSH
• zajištění kvality zdravotní péče MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH
• multicentrická studie MeSH

OBJECTIVES: To explore the association between fetal umbilical and middle cerebral artery (MCA) Doppler abnormalities and outcome in late preterm pregnancies at risk of fetal growth restriction. METHODS: This was a prospective cohort study of singleton pregnancies at risk of fetal growth restriction at 32 + 0 to 36 + 6 weeks of gestation, enrolled in 33 European centers between 2017 and 2018, in which umbilical and fetal MCA Doppler velocimetry was performed. Pregnancies were considered at risk of fetal growth restriction if they had estimated fetal weight and/or abdominal circumference (AC) < 10th percentile, abnormal arterial Doppler and/or a fall in AC growth velocity of more than 40 percentile points from the 20-week scan. Composite adverse outcome comprised both immediate adverse birth outcome and major neonatal morbidity. Using a range of cut-off values, the association of MCA pulsatility index and umbilicocerebral ratio (UCR) with composite adverse outcome was explored. RESULTS: The study population comprised 856 women. There were two (0.2%) intrauterine deaths. Median gestational age at delivery was 38 (interquartile range (IQR), 37-39) weeks and birth weight was 2478 (IQR, 2140-2790) g. Compared with infants with normal outcome, those with composite adverse outcome (n = 93; 11%) were delivered at an earlier gestational age (36 vs 38 weeks) and had a lower birth weight (1900 vs 2540 g). The first Doppler observation of MCA pulsatility index < 5th percentile and UCR Z-score above gestational-age-specific thresholds (1.5 at 32-33 weeks and 1.0 at 34-36 weeks) had the highest relative risks (RR) for composite adverse outcome (RR 2.2 (95% CI, 1.5-3.2) and RR 2.0 (95% CI, 1.4-3.0), respectively). After adjustment for confounders, the association between UCR Z-score and composite adverse outcome remained significant, although gestational age at delivery and birth-weight Z-score had a stronger association. CONCLUSION: In this prospective multicenter study, signs of cerebral blood flow redistribution were found to be associated with adverse outcome in late preterm singleton pregnancies at risk of fetal growth restriction. Whether cerebral redistribution is a marker describing the severity of fetal growth restriction or an independent risk factor for adverse outcome remains unclear, and whether it is useful for clinical management can be answered only in a randomized trial. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.

• MeSH
• arteria cerebri media diagnostické zobrazování   embryologie   MeSH
• arteriae umbilicales diagnostické zobrazování   embryologie   MeSH
• dospělí MeSH
• gestační stáří MeSH
• hmotnost plodu MeSH
• hypotrofický novorozenec MeSH
• lidé MeSH
• narození mrtvého plodu MeSH
• narození živého dítěte MeSH
• novorozenec MeSH
• obvod pasu MeSH
• plod krevní zásobení   diagnostické zobrazování   patofyziologie   MeSH
• porodní hmotnost MeSH
• prospektivní studie MeSH
• pulzatilní průtok MeSH
• referenční hodnoty MeSH
• reologie * MeSH
• růstová retardace plodu diagnostické zobrazování   patofyziologie   MeSH
• těhotenství MeSH
• ultrasonografie dopplerovská * MeSH
• ultrasonografie prenatální * MeSH
• vývoj plodu * MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• novorozenec MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Evropa MeSH