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1.
Ultraschall Med ; 44(1): 56-67, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34768305

RESUMEN

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.


Asunto(s)
Retardo del Crecimiento Fetal , Nacimiento Prematuro , Embarazo , Recién Nacido , Femenino , Humanos , Estudios Prospectivos , Ultrasonografía Prenatal , Recién Nacido Pequeño para la Edad Gestacional , Ultrasonografía Doppler , Peso Fetal , Edad Gestacional , Arterias Umbilicales/diagnóstico por imagen
2.
Ultrasound Obstet Gynecol ; 59(4): 437-449, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34779085

RESUMEN

OBJECTIVE: To develop a standardized sonographic evaluation and reporting system for Cesarean scar pregnancy (CSP) in the first trimester, for use by both general gynecology and expert clinics. METHODS: A modified Delphi procedure was carried out, in which 28 international experts in obstetric and gynecological ultrasonography were invited to participate. Extensive experience in the use of ultrasound to evaluate Cesarean section (CS) scars in early pregnancy and/or publications concerning CSP or niche evaluation was required to participate. Relevant items for the detection and evaluation of CSP were determined based on the results of a literature search. Consensus was predefined as a level of agreement of at least 70% for each item, and a minimum of three Delphi rounds were planned (two online questionnaires and one group meeting). RESULTS: Sixteen experts participated in the Delphi study and four Delphi rounds were performed. In total, 58 items were determined to be relevant. We differentiated between basic measurements to be performed in general practice and advanced measurements for expert centers or for research purposes. The panel also formulated advice on indications for referral to an expert clinic. Consensus was reached for all 58 items on the definition, terminology, relevant items for evaluation and reporting of CSP. It was recommended that the first CS scar evaluation to determine the location of the pregnancy should be performed at 6-7 weeks' gestation using transvaginal ultrasound. The use of magnetic resonance imaging was not considered to add value in the diagnosis of CSP. A CSP was defined as a pregnancy with implantation in, or in close contact with, the niche. The experts agreed that a CSP can occur only when a niche is present and not in relation to a healed CS scar. Relevant sonographic items to record included gestational sac (GS) size, vascularity, location in relation to the uterine vessels, thickness of the residual myometrium and location of the pregnancy in relation to the uterine cavity and serosa. According to its location, a CSP can be classified as: (1) CSP in which the largest part of the GS protrudes towards the uterine cavity; (2) CSP in which the largest part of the GS is embedded in the myometrium but does not cross the serosal contour; and (3) CSP in which the GS is partially located beyond the outer contour of the cervix or uterus. The type of CSP may change with advancing gestation. Future studies are needed to validate this reporting system and the value of the different CSP types. CONCLUSION: Consensus was achieved among experts regarding the sonographic evaluation and reporting of CSP in the first trimester. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Cicatriz , Embarazo Ectópico , Cesárea/efectos adversos , Cicatriz/diagnóstico por imagen , Técnica Delphi , Femenino , Humanos , Embarazo , Embarazo Ectópico/diagnóstico por imagen , Ultrasonografía
3.
Ultrasound Obstet Gynecol ; 58(6): 875-881, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33864313

RESUMEN

OBJECTIVE: To construct reference values for fetal urinary bladder distension in pregnancy and use Z-scores as a diagnostic tool to differentiate posterior urethral valves (PUV) from urethral atresia (UA). METHODS: This was a prospective cross-sectional study in healthy singleton pregnancies aimed at constructing nomograms of fetal urinary bladder diameter and volume between 15 and 35 weeks' gestation. Z-scores of longitudinal bladder diameter (LBD) were calculated and validated in a cohort of fetuses with megacystis with ascertained postnatal or postmortem diagnosis, collected from a retrospective, multicenter study. Correlations between anatomopathological findings, based on medical examination of the infant or postmortem examination, and fetal megacystis were established. The accuracy of the Z-scores was evaluated by receiver-operating-characteristics (ROC)-curve analysis. RESULTS: Nomograms of fetal urinary bladder diameter and volume were produced from three-dimensional ultrasound volumes in 225 pregnant women between 15 and 35 weeks of gestation. A total of 1238 urinary bladder measurements were obtained. Z-scores, derived from the fetal nomograms, were calculated in 106 cases with suspected lower urinary tract obstruction (LUTO), including 76 (72%) cases with PUV, 22 (21%) cases with UA, four (4%) cases with urethral stenosis and four (4%) cases with megacystis-microcolon-intestinal hypoperistalsis syndrome. Fetuses with PUV showed a significantly lower LBD Z-score compared to those with UA (3.95 vs 8.83, P < 0.01). On ROC-curve analysis, we identified 5.2 as the optimal Z-score cut-off to differentiate fetuses with PUV from the rest of the study population (area under the curve, 0.84 (95% CI, 0.748-0.936); P < 0.01; sensitivity, 74%; specificity, 86%). CONCLUSIONS: Z-scores of LBD can distinguish reliably fetuses with LUTO caused by PUV from those with other subtypes of LUTO, with an optimal cut-off of 5.2. This information should be useful for prenatal counseling and management of LUTO. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Feto/diagnóstico por imagen , Ultrasonografía Prenatal/estadística & datos numéricos , Uretra/anomalías , Vejiga Urinaria/diagnóstico por imagen , Vejiga Urinaria/patología , Estudios Transversales , Diagnóstico , Diagnóstico Diferencial , Duodeno/anomalías , Duodeno/diagnóstico por imagen , Duodeno/embriología , Femenino , Enfermedades Fetales/diagnóstico por imagen , Feto/embriología , Feto/patología , Humanos , Síntomas del Sistema Urinario Inferior/diagnóstico por imagen , Síntomas del Sistema Urinario Inferior/embriología , Nomogramas , Tamaño de los Órganos , Embarazo , Estudios Prospectivos , Curva ROC , Valores de Referencia , Estudios Retrospectivos , Uretra/diagnóstico por imagen , Uretra/embriología , Obstrucción Uretral/diagnóstico por imagen , Obstrucción Uretral/embriología , Vejiga Urinaria/anomalías , Vejiga Urinaria/embriología
4.
Neth Heart J ; 29(5): 262-272, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33534113

RESUMEN

BACKGROUND: Elevated N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels at 20 weeks' gestation predict adverse cardiovascular (CV) complications during pregnancy in women with congenital heart disease (CHD). To improve early risk assessment in these women, we investigated the predictive value of first-trimester NT-proBNP for CV complications and its association with ventricular function during pregnancy. METHODS: Pregnant women with CHD, previously enrolled in a prospective national study or evaluated by an identical protocol, were included. Clinical data, echocardiographic evaluation and NT-proBNP measurements were obtained at 12, 20 and 32 weeks' gestation. Elevated NT-proBNP was defined as > 235 pg/ml (95th percentile reference value of healthy pregnant women in the literature). RESULTS: We examined 126 females (mean age 29 years). Elevated NT-proBNP at 12 weeks was associated with CV complications (n = 7, 5.6%, odds ratio 10.9, p = 0.004). Arrhythmias were the most common complication (71%). The negative predictive value of low NT-proBNP to exclude CV complications was 97.2%. In women with CV complications, NT-proBNP levels remained high throughout pregnancy, while a decrease was seen in women without CV complications (p < 0.001 for interaction between group and time). At 12 weeks, higher NT-proBNP levels were associated with impaired subpulmonary ventricular function (p < 0.001) and also with a decline in subpulmonary ventricular function later in pregnancy (p = 0.012). CONCLUSIONS: In this study, first-trimester NT-proBNP levels were associated with adverse CV complications and a decline in subpulmonary ventricular function later in pregnancy in women with CHD. Early NT-proBNP evaluation is useful for tailored care in pregnant women with CHD.

5.
Ultrasound Obstet Gynecol ; 55(6): 776-785, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31613023

RESUMEN

OBJECTIVES: To identify antenatal ultrasound markers that can differentiate between simple and complex gastroschisis and assess their predictive value. METHODS: This was a prospective nationwide study of pregnancies with isolated fetal gastroschisis that underwent serial longitudinal ultrasound examination at regular specified intervals between 20 and 37 weeks' gestation. The primary outcome was simple or complex (i.e. involving bowel atresia, volvulus, perforation or necrosis) gastroschisis at birth. Fetal biometry (abdominal circumference and estimated fetal weight), the occurrence of polyhydramnios, intra- and extra-abdominal bowel diameters and the pulsatility index (PI) of the superior mesenteric artery (SMA) were assessed. Linear mixed modeling was used to compare the individual trajectories of cases with simple and those with complex gastroschisis, and logistic regression analysis was used to estimate the strength of association between the ultrasound parameters and outcome. RESULTS: Of 104 pregnancies with isolated fetal gastroschisis included, four ended in intrauterine death. Eighty-one (81%) liveborn infants with simple and 19 (19%) with complex gastroschisis were included in the analysis. We found no relationship between fetal biometric variables and complex gastroschisis. The SMA-PI was significantly lower in fetuses with gastroschisis than in healthy controls, but did not differentiate between simple and complex gastroschisis. Both intra- and extra-abdominal bowel diameters were larger in cases with complex, compared to those with simple, gastroschisis (P < 0.001 and P < 0.005, respectively). The presence of intra-abdominal bowel diameter ≥ 97.7th percentile on at least three occasions, not necessarily on successive examinations, was associated with an increased risk of the fetus having complex gastroschisis (relative risk, 1.56 (95% CI, 1.02-2.10); P = 0.006; positive predictive value, 50.0%; negative predictive value, 81.4%). CONCLUSIONS: This large prospective longitudinal study found that intra-abdominal bowel dilatation when present repeatedly during fetal development can differentiate between simple and complex gastroschisis; however, the positive predictive value is low, and therefore the clinical usefulness of this marker is limited. © 2019 Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Feto/diagnóstico por imagen , Gastrosquisis/diagnóstico por imagen , Ultrasonografía Prenatal/estadística & datos numéricos , Abdomen/embriología , Biomarcadores/análisis , Biometría , Diagnóstico Diferencial , Femenino , Muerte Fetal/etiología , Gastrosquisis/embriología , Edad Gestacional , Humanos , Recién Nacido , Intestinos/embriología , Modelos Lineales , Modelos Logísticos , Estudios Longitudinales , Arteria Mesentérica Superior/embriología , Polihidramnios/diagnóstico por imagen , Valor Predictivo de las Pruebas , Embarazo , Estudios Prospectivos , Flujo Pulsátil , Medición de Riesgo , Mortinato
6.
Ultrasound Obstet Gynecol ; 56(2): 173-181, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32557921

RESUMEN

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.


Asunto(s)
Desarrollo Fetal , Retardo del Crecimiento Fetal/diagnóstico por imagen , Reología , Ultrasonografía Doppler , Ultrasonografía Prenatal , Adulto , Peso al Nacer , Europa (Continente) , Femenino , Retardo del Crecimiento Fetal/fisiopatología , Peso Fetal , Feto/irrigación sanguínea , Feto/diagnóstico por imagen , Feto/fisiopatología , Edad Gestacional , Humanos , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional , Nacimiento Vivo , Arteria Cerebral Media/diagnóstico por imagen , Arteria Cerebral Media/embriología , Embarazo , Estudios Prospectivos , Flujo Pulsátil , Valores de Referencia , Mortinato , Arterias Umbilicales/diagnóstico por imagen , Arterias Umbilicales/embriología , Circunferencia de la Cintura
7.
Ultrasound Obstet Gynecol ; 53(6): 769-778, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29808509

RESUMEN

OBJECTIVES: Congenital heart disease (CHD) has been associated with reduced fetal head circumference (HC), although the underlying pathophysiology remains undetermined. We aimed to define trends in fetal growth and cerebroplacental Doppler flow, and to investigate their relationship, in fetuses with CHD. METHODS: This was a retrospective study in two fetal medicine units in The Netherlands. We included all fetuses with CHD in whom Doppler flow patterns (middle cerebral artery (MCA) pulsatility index (PI), umbilical artery (UA) PI and cerebroplacental ratio (CPR)) and biometry (HC and abdominal circumference (AC)) had been measured serially after 19 weeks' gestation between January 2010 and November 2016. Fetuses were categorized into three groups based on the expected cerebral arterial oxygen saturation of their particular type of CHD: normal; mild to moderately reduced; severely reduced. Trends over time in Z-scores were analyzed using a linear mixed-effects model. RESULTS: A total of 181 fetuses fulfilled the inclusion criteria. Expected cerebral arterial oxygen saturation in CHD was classified as normal in 44 cases, mild to moderately reduced in 84 and severely reduced in 53. In the cohort overall, average trends over time were significant for both HC and AC Z-scores. HC Z-scores showed a tendency to decrease until 23 weeks, then to increase until 33 weeks, followed by another decrease in the late third trimester. AC Z-scores increased progressively with advancing gestation. MCA-PI and UA-PI Z-scores showed significant trends throughout pregnancy, but CPR Z-scores did not. There were no associations between expected cerebral arterial oxygen saturation and fetal growth. Average trends in MCA-PI Z-scores were significantly different between the three subgroups, whereas those in UA-PI Z-scores and in CPR Z-scores were similar between the subgroups. There was no significant association between MCA-PI and HC Z-scores. CONCLUSIONS: Fetal biometry and Doppler flow patterns are within normal range in fetuses with CHD, but show trends over time. Head growth in fetuses with CHD is not associated with cerebral blood flow pattern or placental function and HC is not influenced by the cerebral arterial oxygen saturation. © 2018 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Desarrollo Fetal , Cardiopatías Congénitas/fisiopatología , Arteria Cerebral Media/fisiopatología , Placenta/irrigación sanguínea , Ultrasonografía Prenatal , Adulto , Biometría , Velocidad del Flujo Sanguíneo , Circulación Cerebrovascular , Femenino , Cardiopatías Congénitas/diagnóstico por imagen , Humanos , Recién Nacido , Arteria Cerebral Media/diagnóstico por imagen , Arteria Cerebral Media/embriología , Países Bajos , Embarazo , Flujo Pulsátil , Estudios Retrospectivos , Sensibilidad y Especificidad
8.
Ultrasound Obstet Gynecol ; 53(4): 520-524, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29978555

RESUMEN

OBJECTIVE: To propose a staging system for congenital lower urinary tract obstruction (LUTO) capable of predicting the severity of the condition and its prognosis. METHODS: This was a national retrospective study carried out at the eight Academic Hospitals in The Netherlands. We collected prenatal and postnatal data of fetuses at high risk of isolated LUTO that were managed conservatively. Postnatal renal function was assessed by the estimated glomerular filtration rate (eGFR), calculated using the Schwartz formula, considering the length of the infant and the creatinine nadir in the first year after birth. Receiver-operating characteristics (ROC) curve analysis, univariate analysis and multivariate logistic regression analysis with stepwise backward elimination were performed in order to identify the best antenatal predictors of perinatal mortality and postnatal renal function. RESULTS: In total, 261 fetuses suspected of having LUTO and managed conservatively were included in the study. The pregnancy was terminated in 110 cases and perinatal death occurred in 35 cases. Gestational age at appearance of oligohydramnios showed excellent accuracy in predicting the risk of perinatal mortality with an area under the ROC curve of 0.95 (P < 0.001) and an optimal cut-off at 26 weeks' gestation. Fetuses with normal amniotic fluid (AF) volume at 26 weeks' gestation presented with low risk of poor outcome and were therefore defined as cases with mild LUTO. In fetuses referred before the 26th week of gestation, the urinary bladder volume (BV) was the best unique predictor of perinatal mortality. ROC curve analysis identified a BV of 5.4 cm3 and appearance of oligohydramnios at 20 weeks as the best threshold for predicting an adverse outcome. LUTO cases with a BV ≥ 5.4 cm3 or abnormal AF volume before 20 weeks' gestation were defined as severe and those with BV < 5.4 cm3 and normal AF volume at the 20 weeks' scan were defined as moderate. Risk of perinatal mortality significantly increased according to the stage of severity, from mild to moderate to severe stage, from 9% to 26% to 55%, respectively. Similarly, risk of severely impaired renal function increased from 11% to 31% to 44%, for mild, moderate and severe LUTO, respectively. CONCLUSIONS: Gestational age at appearance of oligo- or anhydramnios and BV at diagnosis can accurately predict mortality and morbidity in fetuses with LUTO. Our proposed staging system can triage reliably fetuses with LUTO and predict the severity of the condition and its prognosis. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Enfermedades Fetales/diagnóstico , Oligohidramnios/diagnóstico por imagen , Obstrucción Uretral/diagnóstico , Vejiga Urinaria/diagnóstico por imagen , Tratamiento Conservador , Femenino , Edad Gestacional , Tasa de Filtración Glomerular , Humanos , Lactante , Recién Nacido , Modelos Logísticos , Mortalidad Perinatal , Valor Predictivo de las Pruebas , Embarazo , Curva ROC , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Ultrasonografía Prenatal , Obstrucción Uretral/clasificación , Obstrucción Uretral/congénito , Obstrucción Uretral/mortalidad , Vejiga Urinaria/anomalías , Vejiga Urinaria/embriología
9.
Ultrasound Obstet Gynecol ; 53(6): 779-787, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30043466

RESUMEN

OBJECTIVE: Fetal megacystis presents a challenge in terms of counseling and management because of its varied etiology and evolution. The aim of this study was to present a comprehensive overview of the underlying etiologies and structural anomalies associated with fetal megacystis. METHODS: This was a retrospective multicenter study of cases referred to the fetal medicine unit of one of the eight academic hospitals in The Netherlands with a diagnosis of fetal megacystis. For each case, data on and measurements of fetal urinary tract and associated structural anomalies were collected. All available postmortem examinations and postnatal investigations were reviewed in order to establish the final diagnosis. In the first trimester, fetal megacystis was defined as longitudinal bladder diameter (LBD) ≥ 7 mm, and in the second and third trimesters as an enlarged bladder failing to empty during an extended ultrasound examination lasting at least 40 min. RESULTS: Of the 541 pregnancies with fetal megacystis, it was isolated (or solely accompanied by other signs of lower urinary tract obstruction (LUTO)) in 360 (67%) cases and associated with other abnormal ultrasound findings in 181 (33%) cases. The most common associated ultrasound anomaly was an increased nuchal translucency thickness (22%), followed by single umbilical artery (10%) and cardiac defect (10%). A final diagnosis was established in 418 cases, including 222 (53%) cases with isolated LUTO and 60 (14%) infants with normal micturition or minor isolated urological anomalies. In the remaining 136 (33%) cases, concomitant developmental or chromosomal abnormality or genetic syndrome was diagnosed. Overall, 40 chromosomal abnormalities were diagnosed, including trisomy 18 (n = 24), trisomy 21 (n = 5), Turner syndrome (n = 5), trisomy 13 (n = 3) and 22q11 deletion (n = 3). Thirty-two cases presented with anorectal malformations involving the anus, rectum and urogenital tract. In cases with confirmed urethral and anal atresia, megacystis occurred early in pregnancy and the bladder appeared severely distended (the LBD (in mm) was equal to or greater than twice the gestational age (in weeks)). Fetal macrosomia was detected in six cases and an overgrowth syndrome was detected in four cases, comprising two infants with Beckwith-Wiedemann syndrome and two with Sotos syndrome. Megacystis-microcolon-intestinal hypoperistalsis syndrome was diagnosed in five (1%) cases and prenatally suspected only in one case. CONCLUSIONS: Although the main cause of fetal megacystis is LUTO, an enlarged fetal bladder can also be present as a concomitant finding of miscellaneous genetic syndromes, developmental disturbances and chromosomal abnormalities. We provide an overview of the structural anomalies and congenital disorders associated with fetal megacystis and propose a practical guide for the differential diagnosis of genetic syndromes and chromosomal and developmental abnormalities in pregnancies presenting with fetal megacystis, focusing on the morphological examination of the fetus. © 2018 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Anomalías Múltiples/diagnóstico por imagen , Colon/anomalías , Seudoobstrucción Intestinal/diagnóstico por imagen , Ultrasonografía Prenatal , Vejiga Urinaria/anomalías , Anomalías Múltiples/patología , Colon/diagnóstico por imagen , Colon/patología , Femenino , Humanos , Seudoobstrucción Intestinal/congénito , Seudoobstrucción Intestinal/patología , Países Bajos , Embarazo , Resultado del Embarazo , Estudios Retrospectivos , Vejiga Urinaria/diagnóstico por imagen , Vejiga Urinaria/patología
10.
Ultrasound Obstet Gynecol ; 54(3): 359-366, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30334300

RESUMEN

OBJECTIVE: Pregnant women with congenital heart disease (CHD) have an increased risk of abnormal uteroplacental flow, measured from the second trimester onwards, which is associated with pregnancy complications affecting the mother and the fetus. Maternal right ventricular (RV) dysfunction has been suggested as a predisposing factor for impaired uteroplacental flow in these women. The aim of this study was to investigate the association of first-trimester uteroplacental flow measurements with prepregnancy maternal cardiac function and pregnancy complications in women with CHD, with particular focus on the potential role of RV (dys)function. METHODS: This study included 138 pregnant women with CHD from the prospective ZAHARA III study (Zwangerschap bij Aangeboren HARtAfwijkingen; Pregnancy and CHD). Prepregnancy clinical and echocardiographic data were collected. Clinical evaluation, echocardiography (focused on RV function, as assessed by tricuspid annular plane systolic excursion (TAPSE)) and uterine artery (UtA) pulsatility index (PI) measurements were performed at 12, 20 and 32 weeks of gestation. Univariable and multivariable regression analyses were performed to assess the association between prepregnancy variables and UtA-PI during pregnancy. The association between UtA-PI at 12 weeks and cardiovascular, obstetric and neonatal complications was also assessed. RESULTS: On multivariable regression analysis, prepregnancy TAPSE was associated negatively with UtA-PI at 12 weeks of gestation (ß = -0.026; P = 0.036). Women with lower prepregnancy TAPSE (≤ 20 mm vs > 20 mm) had higher UtA-PI at 12 weeks (1.5 ± 0.5 vs 1.2 ± 0.6; P = 0.047). Increased UtA-PI at 12 weeks was associated with obstetric complications (P = 0.003), particularly hypertensive disorders (pregnancy-induced hypertension and pre-eclampsia, P = 0.019 and P = 0.026, respectively). CONCLUSIONS: In women with CHD, RV dysfunction before pregnancy seems to impact placentation, resulting in increased resistance in UtA flow, which is detectable as early as in the first trimester. This, in turn, is associated with pregnancy complications. Early monitoring of uteroplacental flow might be of value in women with CHD with pre-existing subclinical RV dysfunction to identify pregnancies that would benefit from close obstetric surveillance. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Cardiopatías Congénitas/fisiopatología , Circulación Placentaria/fisiología , Complicaciones Cardiovasculares del Embarazo/fisiopatología , Primer Trimestre del Embarazo , Mujeres Embarazadas , Función Ventricular Derecha , Adulto , Femenino , Humanos , Embarazo , Resultado del Embarazo , Estudios Prospectivos , Flujo Pulsátil/fisiología , Arteria Uterina/fisiología , Resistencia Vascular/fisiología
11.
Ultrasound Obstet Gynecol ; 51(4): 463-469, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28397377

RESUMEN

OBJECTIVES: The main aim of this study was to assess the proportion and type of congenital anomalies, both structural and chromosomal, that can be detected at an early scan performed at 12-13 weeks' gestation, compared with at the 20-week structural anomaly scan offered under the present screening policy. Secondary aims were to evaluate the incidence of false-positive findings and ultrasound markers at both scans, and parental choice regarding termination of pregnancy (TOP). METHODS: Sonographers accredited for nuchal translucency (NT) measurement were asked to participate in the study after undergoing additional training to improve their skills in late first-trimester fetal anatomy examination. The early scans were performed according to a structured protocol, in six ultrasound practices and two referral centers in the north-east of The Netherlands. All women opting for the combined test (CT) or with an increased a-priori risk of fetal anomalies were offered a scan at 12-13 weeks' gestation (study group). All women with a continuing pregnancy were offered, as part of the 'usual care', a 20-week anomaly scan. RESULTS: The study group consisted of 5237 women opting for the CT and 297 women with an increased a-priori risk of anomalies (total, 5534). In total, 51 structural and 34 chromosomal anomalies were detected prenatally in the study population, and 18 additional structural anomalies were detected after birth. Overall, 54/85 (63.5%) anomalies were detected at the early scan (23/51 (45.1%) structural and all chromosomal anomalies presenting with either an increased risk at first-trimester screening or structural anomalies (31/34)). All particularly severe anomalies were detected at the early scan (all cases of neural tube defect, omphalocele, megacystis, and multiple severe congenital and severe skeletal anomalies). NT was increased in 12/23 (52.2%) cases of structural anomaly detected at the early scan. Of the 12 cases of heart defects, four (33.3%) were detected at the early scan, five (41.7%) at the 20-week scan and three (25.0%) after birth. False-positive diagnoses at the early scan and at the 20-week scan occurred in 0.1% and 0.6% of cases, respectively, whereas ultrasound markers were detected in 1.4% and 3.0% of cases, respectively. After first- or second-trimester diagnosis of an anomaly, parents elected TOP in 83.3% and 25.8% of cases, respectively. CONCLUSIONS: An early scan performed at 12-13 weeks' gestation by a competent sonographer can detect about half of the prenatally detectable structural anomalies and 100% of those expected to be detected at this stage. Particularly severe anomalies, often causing parents to choose TOP, are amenable to early diagnosis. The early scan is an essential part of modern pregnancy care. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Anomalías Congénitas , Pruebas de Detección del Suero Materno/estadística & datos numéricos , Medida de Translucencia Nucal/estadística & datos numéricos , Trisomía/genética , Adolescente , Adulto , Aberraciones Cromosómicas , Anomalías Congénitas/diagnóstico por imagen , Anomalías Congénitas/epidemiología , Anomalías Congénitas/genética , Reacciones Falso Positivas , Femenino , Edad Gestacional , Humanos , Tamizaje Masivo , Persona de Mediana Edad , Embarazo , Resultado del Embarazo/epidemiología , Primer Trimestre del Embarazo , Adulto Joven
13.
Ultrasound Obstet Gynecol ; 52(6): 739-743, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29266464

RESUMEN

OBJECTIVE: To propose a clinical score for the optimal antenatal diagnosis of fetal lower urinary tract obstruction (LUTO) in the second and third trimesters of pregnancy, as an alternative to the commonly used ultrasound triad of megacystis, keyhole sign and hydronephrosis. METHODS: This was a national retrospective study carried out at the eight tertiary fetal medicine units (FMUs) in The Netherlands. Only cases referred for megacystis from the second trimester onwards and with a clear postnatal diagnosis were included in the study. At referral, data were collected on amniotic fluid volume, renal cortical appearance, bladder volume, hydronephrosis, fetal ascites, ureteral size, keyhole sign, fetal sex and gestational age. Multivariate analysis was performed, starting by including all antenatal variables, and then excluding the weakest predictors using the backward stepwise strategy. RESULTS: Over a 7-year period, 312 fetuses with a diagnosis of megacystis were referred to the eight Dutch tertiary FMUs. A final diagnosis was achieved in 143 cases, including 124 of LUTO and 19 reclassified after birth as non-obstructive megacystis. The optimal bladder volume cut-off for prediction of LUTO was 35 cm3 (area under the curve (AUC) = 0.7, P = 0.03). The clinical score formulated on the basis of the multivariate analysis included fetal sex, degree of bladder distension, ureteral size, oligo- or anhydramnios and gestational age at referral. The combination of these five variables demonstrated good accuracy in discriminating LUTO from non-obstructive megacystis (AUC = 0.84, P < 0.001), compared with the poor performance of the ultrasound triad (AUC = 0.63, P = 0.07). CONCLUSIONS: We propose a clinical score that combines five antenatal variables for the prospective diagnosis of congenital LUTO. This score showed good discriminative capacity in predicting LUTO, and better diagnostic accuracy compared with that of the classic ultrasound triad. Future studies to validate these results should be carried out in order to refine antenatal management of LUTO and prevent inappropriate fetal interventions. © 2017 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Duodeno/anomalías , Enfermedades Fetales/diagnóstico , Hidronefrosis/diagnóstico , Diagnóstico Prenatal/métodos , Vejiga Urinaria/anomalías , Femenino , Edad Gestacional , Humanos , Masculino , Embarazo , Primer Trimestre del Embarazo , Segundo Trimestre del Embarazo , Estudios Retrospectivos
15.
Ultrasound Obstet Gynecol ; 49(5): 599-606, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27255564

RESUMEN

OBJECTIVES: To identify maternal-, operator- and procedure-related variables that affect procedure-related pregnancy loss after transcervical (TC) and transabdominal (TA) chorionic villus sampling (CVS) and amniocentesis and to estimate the rates of spontaneous and procedure-related loss in comparable subgroups of women. METHODS: This was a retrospective cohort study conducted at the University Medical Center Groningen and the Academic Medical Center, The Netherlands. Databases of both centers were searched to identify singleton pregnancies that had undergone a combined test and/or anomaly scan at around 20 weeks' gestation, or an invasive procedure (CVS and/or amniocentesis) between January 2001 and December 2011. Maternal characteristics, obstetric history, technical aspects of the invasive procedure, ultrasound examinations and fetal and neonatal outcomes were available for 29 201 cases. Women were categorized, according to the type of examination they had received, into the following five groups: first-trimester combined test (and 20-week anomaly scan); 20-week anomaly scan only; CVS; amniocentesis; amniocentesis after unsuccessful CVS. Rates of fetal loss were compared between groups. RESULTS: Variables significantly associated with a higher rate of fetal loss were, for CVS, repeat attempts during the procedure, use of TC cannula instead of biopsy forceps, gestational age at procedure ≥ 13 weeks and a pregnancy after assisted reproductive techniques, and, for amniocentesis, if indication was fetal anomaly or family history of anomalies and repeat attempts during the procedure. In women aged ≥ 36 years who did not undergo an invasive procedure, spontaneous fetal loss rate (FLR) after first-trimester combined test was 1.40%, whereas after CVS, FLR was 2.76% and 2.43% for a TC and TA approach, respectively. The additional risk of fetal loss with TC-CVS was therefore 1.36% (1 : 74), which varied according to the instrument used (0.27% for forceps and 3.12% for cannula), and with TA-CVS was 1.03% (1 : 97). In women aged ≥ 36 years who underwent a 20-week anomaly scan only, spontaneous FLR was 0.63%. In women who underwent amniocentesis solely because of advanced maternal age, FLR was 1.11%. The additional risk of fetal loss with amniocentesis was 0.48% (1 : 208). CONCLUSION: The total rate of procedure-related fetal loss after TA- and TC-CVS and amniocentesis appears lower than the risks on which women are currently counseled. There was a trend for a decrease in risk when the level of experience of the operator increased. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Amniocentesis/efectos adversos , Muestra de la Vellosidad Coriónica/efectos adversos , Adulto , Competencia Clínica , Estudios de Cohortes , Bases de Datos Factuales , Femenino , Muerte Fetal , Humanos , Países Bajos/epidemiología , Embarazo , Resultado del Embarazo , Estudios Retrospectivos , Mortinato
16.
Ultrasound Obstet Gynecol ; 50(4): 458-463, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28133847

RESUMEN

OBJECTIVES: To investigate the natural history of fetal megacystis from diagnosis in utero to postnatal outcome, and to identify prognostic indicators of spontaneous resolution and postnatal outcome after resolution. METHODS: This was a national retrospective cohort study. Fetal megacystis was defined in the first trimester as a longitudinal bladder diameter (LBD) ≥ 7 mm, and in the second and third trimesters as an enlarged bladder failing to empty during the entire extended ultrasound examination. LBD and gestational age (GA) at resolution were investigated with respect to likelihood of resolution and postnatal outcome, respectively. Sensitivity, specificity and area under the receiver-operating characteristics curve (AUC) were calculated. RESULTS: In total, 284 cases of fetal megacystis (93 early megacystis, identified before the 18th week, and 191 late megacystis, identified at or after the 18th week) were available for analysis. Spontaneous resolution occurred before birth in 58 (20%) cases. In cases with early megacystis, LBD was predictive of the likelihood of spontaneous resolution (sensitivity, 80%; specificity, 79%; AUC, 0.84), and, in the whole population, GA at regression was predictive of postnatal outcome, with an optimal cut-off at 23 weeks (sensitivity, 100%; specificity, 82%; AUC, 0.91). In the group with early megacystis, the outcome was invariably good when resolution occurred before the 23rd week of gestation, whereas urological sequelae requiring postnatal surgery were diagnosed in 3/8 (38%) cases with resolution after 23 weeks. In the group with late megacystis, spontaneous resolution was associated with urological complications after birth, ranging from mild postnatal hydronephrosis in infants with resolution before 23 weeks, to more severe urological anomalies requiring postnatal surgery in those with resolution later in pregnancy. This supports the hypothesis that an early resolution of megacystis is often related to a paraphysiological bladder enlargement that resolves early in pregnancy without consequences, while antenatal resolution occurring later in pregnancy (after the 23rd week of gestation) should suggest a pathological condition with urological sequelae. CONCLUSIONS: In fetal megacystis, LBD and GA at regression can be used as predictors of resolution and outcome, respectively. These parameters could help in fine-tuning the prognosis and optimizing the frequency of follow-up scans. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Duodeno/anomalías , Enfermedades Fetales/diagnóstico por imagen , Ultrasonografía Prenatal , Vejiga Urinaria/anomalías , Vejiga Urinaria/diagnóstico por imagen , Duodeno/diagnóstico por imagen , Duodeno/patología , Femenino , Enfermedades Fetales/patología , Edad Gestacional , Humanos , Embarazo , Resultado del Embarazo , Primer Trimestre del Embarazo , Pronóstico , Curva ROC , Remisión Espontánea , Estudios Retrospectivos , Vejiga Urinaria/embriología , Vejiga Urinaria/patología
18.
Ultrasound Obstet Gynecol ; 49(2): 231-239, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27071979

RESUMEN

OBJECTIVE: Pregnancy in women with surgically corrected tetralogy of Fallot (ToF) is associated with cardiac, obstetric and neonatal complications. We compared uteroplacental Doppler flow (UDF) measurements and pregnancy outcome in women with ToF and in healthy women and aimed to assess whether a relationship exists between cardiac function and UDF in women with ToF. METHODS: We evaluated prospectively pregnant women with ToF and healthy pregnant women from the ZAHARA studies. Clinical evaluation, standardized echocardiography and UDF measurements were performed at 20 and 32 weeks' gestation. RESULTS: We included 62 women with ToF and 69 healthy controls. Cardiac complications, mostly arrhythmia, occurred in 8.1% of women with ToF. There was a higher incidence of small-for-gestational age (21.0% vs 4.4%, P = 0.004) and low birth weight (16.1% vs 2.9%, P = 0.009) in the group of women with ToF than in healthy controls. In women with ToF, early diastolic notching of uterine artery waveform at 20 and 32 weeks occurred more frequently (9.8% vs 1.5%, P = 0.034 and 7.0% vs 0%, P = 0.025, respectively) and the umbilical artery pulsatility index at 32 weeks was higher (1.02 ± 0.20 vs 0.94 ± 0.17, P = 0.015) than in healthy controls. Right ventricular function parameters prepregnancy and at 20 weeks' gestation were significantly associated with abnormal UDF. UDF parameters were associated with adverse neonatal outcome. CONCLUSION: The majority of women with surgically corrected ToF tolerate pregnancy well. However, UDF indices are more frequently abnormal in these women, suggesting impaired placentation. The association of impaired right ventricular function parameters with abnormal UDF suggests that cardiac dysfunction contributes to defective placentation or placental perfusion mismatch and may explain the increased incidence of obstetric and neonatal complications. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Ecocardiografía Doppler/métodos , Placenta/diagnóstico por imagen , Tetralogía de Fallot/diagnóstico por imagen , Ultrasonografía Prenatal/métodos , Adulto , Arritmias Cardíacas/diagnóstico por imagen , Femenino , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional , Embarazo , Resultado del Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Estudios Prospectivos , Tetralogía de Fallot/complicaciones , Tetralogía de Fallot/cirugía
19.
Ultrasound Obstet Gynecol ; 50(3): 347-352, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27854382

RESUMEN

OBJECTIVE: In the TRUFFLE (Trial of Randomized Umbilical and Fetal Flow in Europe) study on the outcome of early fetal growth restriction, women were allocated to one of three groups of indication for delivery according to the following monitoring strategies: (1) reduced fetal heart rate (FHR) short-term variation (STV) on cardiotocography (CTG); (2) early changes in fetal ductus venosus (DV) waveform (DV-p95); and (3) late changes in fetal DV waveform (DV-no-A). However, many infants per monitoring protocol were delivered because of safety-net criteria, for maternal or other fetal indications, or after 32 weeks of gestation when the protocol was no longer applied. The objective of the present posthoc subanalysis was to investigate the indications for delivery in relation to 2-year outcome in infants delivered before 32 weeks to further refine management proposals. METHODS: We included all 310 cases of the TRUFFLE study with known outcome at 2 years' corrected age and seven fetal deaths, excluding seven cases with inevitable perinatal death. Data were analyzed according to the allocated fetal monitoring strategy in combination with the indication for delivery. RESULTS: Overall, only 32% of liveborn infants were delivered according to the specified monitoring parameter for indication for delivery; 38% were delivered because of safety-net criteria, 15% for other fetal reasons and 15% for maternal reasons. In the CTG-STV group, 51% of infants were delivered because of reduced STV. In the DV-p95 group, 34% of infants were delivered because of abnormal DV and, in the DV-no-A group, only 10% of infants were delivered accordingly. The majority of infants in the DV groups were delivered for the safety-net criterion of spontaneous decelerations in FHR. Two-year intact survival was highest in the DV groups combined compared with the CTG-STV group (P = 0.05 for live births only, P = 0.21 including fetal death), with no difference between DV groups. A poorer outcome in the CTG-STV group was restricted to infants delivered because of FHR decelerations in the safety-net subgroup. Infants delivered because of maternal reasons had the highest birth weight and a non-significantly higher intact survival. CONCLUSIONS: In this subanalysis of infants delivered before 32 weeks, the majority were delivered for reasons other than the allocated monitoring strategy indication. Since, in the DV group, CTG-STV criteria were used as a safety net but in the CTG-STV group, no DV safety-net criteria were applied, we speculate that the slightly poorer outcome in the CTG-STV group might be explained by the absence of DV data. The optimal timing of delivery of fetuses with early intrauterine growth restriction may therefore be best determined by monitoring them longitudinally, with both DV and CTG monitoring. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Parto Obstétrico , Retardo del Crecimiento Fetal/mortalidad , Monitoreo Fetal , Ultrasonografía Prenatal , Arterias Umbilicales/fisiopatología , Cardiotocografía , Femenino , Retardo del Crecimiento Fetal/fisiopatología , Feto/irrigación sanguínea , Edad Gestacional , Humanos , Recién Nacido , Masculino , Países Bajos , Embarazo , Resultado del Embarazo , Flujo Pulsátil , Análisis de Supervivencia , Arterias Umbilicales/diagnóstico por imagen
20.
Ultrasound Obstet Gynecol ; 50(1): 71-78, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27484356

RESUMEN

OBJECTIVES: To explore whether, in early fetal growth restriction (FGR), the longitudinal pattern of fetal heart rate (FHR) short-term variation (STV) can be used to identify imminent fetal distress and whether abnormalities of FHR recordings are associated with 2-year infant outcome. METHODS: The original TRUFFLE study assessed whether, in early FGR, delivery based on ductus venosus (DV) Doppler pulsatility index (PI), in combination with safety-net criteria of very low STV on cardiotocography (CTG) and/or recurrent FHR decelerations, could improve 2-year infant survival without neurological impairment in comparison with delivery based on CTG monitoring only. This was a secondary analysis of women who delivered before 32 weeks and had consecutive STV data recorded > 3 days before delivery and known infant outcome at 2 years of age. Women who received corticosteroids within 3 days of delivery were excluded. Individual regression line algorithms of all STV values, except the last one before delivery, were calculated. Life tables and Cox regression analysis were used to calculate the daily risk for low STV or very low STV and/or FHR decelerations (below DV group safety-net criteria) and to assess which parameters were associated with this risk. Furthermore, it was assessed whether STV pattern, last STV value or recurrent FHR decelerations were associated with 2-year infant outcome. RESULTS: One hundred and forty-nine women from the original TRUFFLE study met the inclusion criteria. Using the individual STV regression lines, prediction of a last STV below the cut-off used by the CTG monitoring group had sensitivity of 42% and specificity of 91%. For each day after study inclusion, the median risk for low STV (CTG group cut-off) was 4% (interquartile range (IQR), 2-7%) and for very low STV and/or recurrent FHR decelerations (below DV group safety-net criteria) was 5% (IQR, 4-7%). Measures of STV pattern, fetal Doppler (arterial or venous), birth-weight multiples of the median and gestational age did not usefully improve daily risk prediction. There was no association of STV regression coefficients, a low last STV and/or recurrent FHR decelerations with short- or long-term infant outcomes. CONCLUSION: The TRUFFLE study showed that a strategy of DV monitoring with safety-net criteria of very low STV and/or recurrent FHR decelerations for delivery indication could increase 2-year infant survival without neurological impairment. This post-hoc analysis demonstrates that, in early FGR, the daily risk of abnormal CTG, as defined by the DV group safety-net criteria, is 5%, and that prediction is not possible. This supports the rationale for CTG monitoring more often than daily in these high-risk fetuses. Low STV and/or recurrent FHR decelerations were not associated with adverse infant outcome and it appears safe to delay intervention until such abnormalities occur, as long as DV-PI is within normal range. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Retardo del Crecimiento Fetal/diagnóstico por imagen , Corazón Fetal/fisiología , Frecuencia Cardíaca Fetal/fisiología , Arteria Cerebral Media/diagnóstico por imagen , Adulto , Cardiotocografía , Preescolar , Femenino , Retardo del Crecimiento Fetal/mortalidad , Retardo del Crecimiento Fetal/fisiopatología , Humanos , Lactante , Recién Nacido , Estudios Longitudinales , Arteria Cerebral Media/fisiología , Embarazo , Resultado del Embarazo , Flujo Pulsátil , Análisis de Supervivencia , Ultrasonografía Prenatal
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