Prediction of fetal anemia in rhesus disease by measurement of fetal middle cerebral artery peak systolic velocity

Quantitative Analysis of Morphology and Function in the Fetal Heart with Severe Tricuspid Regurgitation by Speckle Tracking Imaging

Morphology and function in a fetal heart with severe tricuspid regurgitation remains challenging. The aim of this study was to assess cardiac morphology and function in fetuses with severe tricuspid regurgitation by fetal heart quantification (HQ) and to assess the practical value of fetal HQ. Clinical information was analyzed for 63 pregnant women who underwent fetal cardiac ultrasonography. The women were divided into those who had a fetus with severe tricuspid regurgitation (n = 20) and those with a normal fetus (n = 40). The global sphericity index (GSI), fractional area change (FAC), and global longitudinal strain (GLS) of both ventricles and the sphericity index (SI) and fractional shortening (FS) of 24 segments were quantified by fetal HQ using speckle tracking imaging. Fetuses with severe tricuspid regurgitation had a significantly lower GSI (1.14 ± 0.10 vs. 1.26 ± 0.08, p < 0.001) and a higher GSI Z-score (-0.98 ± 1.01 vs. 0.25 ± 0.87, p < 0.001) as well as a significantly lower right ventricular FAC (36.50 ± 7.34% vs. 45.19 ± 3.39%, p < 0.001), FAC Z-score (-1.02 ± 1.41 vs. 0.49 ± 0.74, p < 0.001), and GLS (-21.01 ± 5.66% vs. 45.19 ± 3.49%, p < 0.001). The SI and SI Z-score were significantly lower in segments 1-18 of the right ventricle in fetuses with severe tricuspid regurgitation (p < 0.05); furthermore, FS of segments 1-12 and 19-24 and the FS Z-score of segments 18-24 were significantly lower in fetuses with severe tricuspid regurgitation (p < 0.05). Fetal HQ is useful for evaluation of cardiac morphology and function in fetuses with severe tricuspid regurgitation and can provide important reference information for both clinical diagnosis and treatment.

Color Doppler ultrasound in high-low risk pregnancies and its relationship to fetal outcomes: a cross-sectional study

Objective

To calculate the multivessel color Doppler indices in high-risk and low-risk pregnancies and relate these to fetal outcomes.

Methods

The investigation involved 60 patients who were pregnant. The patients were separated into groups according to assessment of low and high risk. The patients underwent color Doppler ultrasonography to detect the maternal and fetal blood vessels, and the measured Doppler indices were then analyzed for any association with fetal outcomes.

Results

The gestational stages (in weeks) of the participants at the respective times of investigation and delivery were 32.06 ± 2.98 and 36.2 ± 1.78 in the low-risk group and 29.21 ± 1.95 and 29.83 ± 1.86 in the high-risk group. The pulsatility index (PI), resistive index (RI), and systolic/diastolic ratio (SD) decreased with gestation length in the low-risk group, whereas in the high-risk group, these values increased in the uterine and umbilical arteries. With increased gestational stage, MCA-PSV (peak systolic velocity) in the middle cerebral artery (MCA) increased, while PI decreased. Pulsatile and reversal flow of the uterine vein, the vein of Galen, and the umbilical vein were noted in high-risk pregnancies, and these negatively affected the fetal outcome. The fetal venous parameters were more specific and sensitive for predicting an unfavorable fetal outcome than the arterial factors, with a greater negative predictive value.

Conclusion

The results of our study indicate that abnormal Doppler indices of the blood vessels in high-risk pregnant patients will result in adverse clinical outcomes. Therefore, the patients can be monitored and managed accordingly using Doppler ultrasonography.

Fetal Ductus Arteriosus Premature Constriction

This study aimed to investigate the connections between the echocardiography indices of fetal ductus arteriosus premature constriction and newborn prognosis by analyzing 22 cases of spontaneous fetal ductus arteriosus premature constriction.An ultrasonic instrument was used to observe prenatal fetal heart state, combine clinical examination data and echocardiographic results after delivery, summarize the ultrasound manifestations and imaging characteristics, and analyze the prognosis of the fetus.In all cases, fetal ductus arteriosus premature constriction occurred in the third trimester of pregnancy (34 + 1 to 41 weeks), and no abnormality in extracardiac organs were observed. Seven neonates required respiratory support due to the accompanying severe tricuspid regurgitation. The remaining 15 neonates did not receive respiratory support, including 4 with severe tricuspid regurgitation, 5 with moderate regurgitation, and 6 with mild regurgitation. Significant differences were observed in the fetal right atrium size and tricuspid regurgitation severity between the neonatal respiratory support group and non-respiratory support group. Furthermore, there were statistical differences in the ductus arteriosus inner diameter and pulsation index between the two groups.The severity of fetal ductus arteriosus premature contraction accompanied by tricuspid regurgitation and right atrium enlargement can predict the immediate prognosis of the newborn and provide guidance for the clinical judgment of the timing of pregnancy termination.

Diagnostic Performance of Doppler Ultrasonography for the Detection of Fetal Anemia: A Meta-analysis

This study evaluates the diagnostic performance of Doppler ultrasound in diagnosing fetal anemia. Data were taken from relevant study reports published in peer-reviewed journals identified after a literature search in electronic databases. Random effects meta-analyses were performed by pooling the effect sizes of diagnostic indices (sensitivity, specificity, positive/negative predictive values, and false-positive rate) or correlation coefficients reported by individual studies. As a result, 31 studies (1848 pregnancies; gestation age, 28.25 weeks [95% confidence interval {CI}, 26.87-29.63]) were included in the meta-analysis. Anemia was found in 63.7% (95% CI, 49.7-77.7) fetuses, and severe anemia was found in 36.7% (95% CI, 26.9-46.4) fetuses. Sensitivity and specificity of Doppler ultrasound for detecting fetal anemia in alloimmunized fetuses at middle cerebral artery peak systolic velocity cutoff of 1.5 multiple of median for gestation age were 83.42% (95% CI, 71.75-95.09) and 80.30% (95% CI, 73.58-87.02), respectively. Positive predictive value, negative predictive value, and false-positive rate were 76.35% (95% CI, 65.98-86.72), 80.0% (95% CI, 76.63-83.37), and 10.4% (95% CI, 5.9-14.9), respectively. Correlation coefficient between hematological anemia and Doppler ultrasound-measured blood flow velocity was -0.706 (95% CI, -0.765 to -0.635; P < 0.00001). In conclusion, Doppler ultrasound-measured middle cerebral artery peak systolic velocity at 1.5 multiple of median provides good diagnostic strength for the detection of alloimmunized fetal anemia. A strong correlation between Doppler velocimetric measures and hematological anemia is also observed.

Magnetic Resonance Imaging: A New Tool to Optimize the Prediction of Fetal Anemia?

INTRODUCTION

The false-positive rate in the prediction of fetal anemia is 10-15%. We investigated if a new, noninvasive MRI method used as a supplement to ultrasound could improve the prediction.

METHODS

Fetuses suspected of anemia and controls were scanned in a 1.5-tesla MRI scanner 1-4 times during pregnancy. Cases were scanned before and after intrauterine blood transfusion with a T1-mapping MRI sequence in a cross-section of the umbilical vein.

RESULTS

Inclusion of 8 cases and 11 controls resulted in 10 case scans (2 cases were included twice) and 33 control scans. In controls, the T1 relaxation time was 1,005-1,391 ms; in cases with severe anemia, 1,505-1,595 ms, moderate anemia 1,503-1,525 ms, and no/mild anemia 1,245-1,410 ms. After blood transfusions, values dropped to 1,123-1,288 ms. The mean value in moderate and severe anemic cases was 275 ms higher than in controls (95% CI 210-341 ms, p < 0.0001), and after blood transfusion it was comparable to controls (3 ms, 95% CI -62 to 68 ms, p = 0.934). A 1,450-ms cut-off would have identified all cases in need of blood transfusion with no false-positive cases.

CONCLUSIONS

Our findings indicate a potential for this new MRI method to improve the prediction of fetal anemia as a supplement to ultrasound.

Review of the correlation between blood flow velocity and polycythemia in the fetus, neonate and adult: appropriate diagnostic levels need to be determined for twin anemia-polycythemia sequence

Twin anemia-polycythemia sequence (TAPS) is recognized increasingly antenatally by the demonstration of an anemic twin and a polycythemic cotwin using the middle cerebral artery peak systolic velocity (MCA-PSV). While the MCA-PSV has been shown to correlate well with anemia in singleton fetuses, the evidence to support its use to diagnose fetal polycythemia appears to be less clear-cut. We aimed to evaluate fetal, neonatal and adult literature used to support the use of MCA-PSV for the diagnosis of polycythemia. Comprehensive literature searches were performed for ultrasound evidence of polycythemia in the human fetus, neonate and adult using key search terms. Only manuscripts in the English language with an abstract were considered for the review, performed in June 2014. Fifteen manuscripts were found for the human fetus, including 38 cases of TAPS. Nine of these defined fetal polycythemia as MCA-PSV < 0.8 multiples of the median (MoM), five used < 1.0 MoM and one used 0.8-1.0 MoM. Only two studies, involving a total of 15 cases, proposed a diagnostic level, acknowledging false-positive and -negative cases, though neither reported sensitivities or specificities. Six neonatal studies (96 neonates) demonstrated evidence of decreased cerebral velocities in polycythemia and a consequent increase with hemodilution. In the adult, five studies (57 polycythemic adults) demonstrated increased flow or velocity with hemodilution. Neither neonatal nor adult studies conclusively defined levels for screening for polycythemia. Despite widespread adoption of a cut-off of < 0.8 MoM in the published literature for the polycythemic fetus in TAPS, this is based upon minimal evidence, with unknown sensitivity and specificity. We recommend caution in excluding TAPS based purely upon the absence of a reduced MCA-PSV.

A prospective cross-sectional study of fetal middle cerebral artery peak systolic velocity in a normal obstetric population attending an Indian Medical College

PURPOSE

Fetal middle cerebral artery peak systolic velocity (MCA-PSV) is now an established method of noninvasive diagnosis of moderate to severe fetal anemia of different origins. This being a population-based parameter, it may have different values in individuals from different locations. A standard local reference range of normal individuals specific to each geographic locality is therefore needed.

MATERIALS AND METHODS

Fetal MCA-PSV was measured in 1,015 healthy pregnant women attending the antenatal ultrasound clinic at least once between 12 and 40 weeks of gestation (35 patients per week of gestation). Statistical analysis was done using the SPSS 12 software.

RESULTS

A positive correlation between MCA-PSV and gestational age was found. MCA-PSV was seen to increase with advancing gestational age. The Tukey-Kramer multiple comparisons test showed a normal distribution that was highly significant (p < 0.01). The multiples of median values of fetal MCA-PSV to label a fetus as severely anemic were consistently and significantly lower than internationally accepted values.

CONCLUSIONS

A normal reference range of fetal MCA-PSV for local use was thus scientifically and successfully constructed. Significant differences between local values and internationally accepted value were found.

Middle cerebral artery peak systolic velocity and ductus venosus velocity in the investigation of nonimmune hydrops

PURPOSE

This study was performed to investigate the cause of nonimmune hydrops fetalis by measuring the peak systolic velocity (PSV) in the middle cerebral artery (MCA) and velocity waveforms of the ductus venosus (DV) with Doppler.

METHODS

This cross-sectional study was done on 19 pregnancies referred to three university teaching hospitals for further investigation of nonimmune hydrops fetalis in 2007 and 2008. The MCA-PSV and DV velocity waveforms were recorded in all fetuses. Anemia was investigated in cases with MCA-PSV values greater than 1.50 MoM (multiple of the median). Cardiovascular causes and chromosomal abnormalities were investigated in fetuses with abnormal DV velocity.

RESULTS

Four of 19 fetuses had MCA-PSV values greater than 1.50 MoM. The causes of anemia were cytomegalovirus, parvovirus B19 infections, congenital heart disease, and Turner syndrome. Four cases had reversed flow in the DV; three of them had congenital heart disease on echocardiography; and one had a normal echocardiogram, but an abnormal karyotype was detected.

CONCLUSION

Assessment of the MCA-PSV and DV velocity waveforms during sonographic examination of fetuses with nonimmune hydrops fetalis may improve our knowledge about the etiology of this condition.

Identification of fetuses with hemoglobin Bart's disease using middle cerebral artery peak systolic velocity

OBJECTIVES

To determine the sensitivity and specificity of middle cerebral artery peak systolic velocity (MCA-PSV) in mid-pregnancy for the identification of homozygous alpha-thalassemia-1 (hemoglobin (Hb) Bart's disease) in fetuses at risk of the disease.

METHODS

A total of 88 pregnancies (91 fetuses) at risk of Hb Bart's disease and undergoing MCA-PSV measurement before cordocentesis at 18-22 weeks of gestation were recruited into the study. Definitive diagnosis was made using the gold standard technique of Hb typing by high-performance liquid chromatography.

RESULTS

The mean +/- SD age of the 88 pregnant women recruited into the study was 28.3 +/- 5.7 years, the gestational age was 18.8 +/- 1.1 weeks and the incidence of Hb Bart's disease was 22% (20 fetuses). Using MCA-PSV above 1.5 multiples of the median as a cut-off point, the sensitivity of MCA-PSV for detecting affected fetuses was 85% (17/20 cases), with a specificity of 100%, and positive and negative predictive values of 100% and 95.9% respectively. Three of 20 fetuses with Hb Bart's disease had normal MCA-PSV.

CONCLUSIONS

MCA-PSV assessment in mid-pregnancy is a useful method for identifying Hb Bart's disease with high sensitivity and specificity among fetuses at risk, and may allow avoidance of unnecessary cordocentesis in some cases.

Prenatal diagnosis of transient abnormal myelopoiesis in a Down syndrome fetus

We report a case of transient abnormal myelopoiesis in a Down syndrome fetus diagnosed at 28⁺³ weeks of gestation that rapidly progressed to intrauterine death 10 days later. Fetal hepatosplenomegaly with cerebral ventriculomegaly, although not specific, may be a suggestive finding of Down syndrome with transient abnormal myelopoiesis. Prompt fetal blood sampling for liver function test and chromosomal analysis are mandatory for early detection and management.

Middle cerebral artery peak systolic velocity of healthy fetuses in the first half of pregnancy

OBJECTIVE

The purpose of this study was to establish normative data of middle cerebral artery (MCA) peak systolic velocity (PSV) in the first half of normal pregnancies (11-22 weeks).

METHODS

A prospective cross-sectional descriptive study was conducted in which low-risk pregnant women whose pregnancies were singleton with accurate gestational age were recruited into the study. All neonates were subsequently proven to be healthy at birth. The sonographic measurements of MCA PSV were performed by the same examiner with a high-resolution machine.

RESULTS

The total number of measurements was 410, and the number of measurements for each gestational week ranged from 30 to 40. The best regression model between gestational week and placental thickness was observed to be a linear function, and reference curves were constructed. The results showed a continuous increase in MCA PSV over the period from 11 to 22 weeks. During the period of study, 3 fetuses with hemoglobin Bart disease in the first half of pregnancy were encountered, and all of them had PSV of greater than the 95th percentile as well as 1.5 multiples of the median for each gestational week.

CONCLUSIONS

A nomogram of MCA PSV for each gestational age from 11 to 22 weeks was constructed. These reference ranges may be useful noninvasive tools in risk assessment for fetal anemia in early pregnancy, especially due to hemoglobin Bart disease.

Hemodynamic changes in the fetal arteries during the second half of pregnancy assessed by Doppler velocimetry

The applicability of Doppler velocimetry has been well established regarding intrauterine growth restriction and fetal hypoxia. This method can also be used to determine fetal anemia and cardiac malformations. The main fetal arteries evaluated by Doppler velocimetry are the middle cerebral artery and the umbilical artery. However, the fetal aorta is responsible for the distribution of blood flow to the upper and lower extremities of the human body and should also be properly valued. In order to characterize abnormalities in the arteries of high-risk fetuses, it is necessary to know the hemodynamic modifications of normal fetuses. On this basis, the authors performed a review of fetal hemodynamics evaluated by Doppler velocimetry in the fetal aorta and middle cerebral and umbilical arteries during the second half of pregnancy. The study of fetal vessels by Doppler velocimetry indirectly evaluates the hemodynamic changes occurring in fetuses at risk. In this respect, we emphasize the changes in Doppler velocimetry occurring in fetal anemia, in restricted intrauterine growth, and in normal fetuses.

Doppler waveform indices of the Middle Cerebral Artery of normal fetuses in the first half of pregnancy in the Thai population

OBJECTIVE

To establish the reference ranges of middle cerebral artery (MCA) Doppler indices including pulsatility index (PI), resistance index (RI) and peak systolic velocity (PSV) of the Thai fetuses at gestational age of 11-20 weeks.

METHODS

A descriptive cross-sectional study was conducted at Department of Obstetrics and Gynecology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand. Normal singleton pregnancies between 11 and 20 weeks of gestation were recruited into the study for measurements of MCA Doppler indices between November 2005 and August 2006. The trans-abdominal ultrasound, Aloka Model Prosound 5000 (Tokyo) was used. The MCA Doppler data were analyzed for median, 5th, and 95th percentile for each gestational week. The best-fit mathematical model was derived.

RESULTS

A total of 300 measurements, with average of 30 +/- 7.35 per gestational week (mean +/- SD) and range 23-45 per gestational week, were obtained from 149 patients. Regression analysis yielded the best-fitted equation of quadratic function as follows: PI = 8.421 - 0.705(GA) + 0.018(GA(2)) (r (2) = 0.452), RI = 1.54 - 0.073(GA) + 0.002(GA(2)) (r (2) = 0.309), PSV = -63.456 + 9.425(GA) - 0.262(GA(2)) (r (2) = 0.504).

CONCLUSION

A nomogram for MCA Doppler indices, including PI, RI and PSV ratio for each gestational age during 11-20 weeks was constructed. This may be a useful aid in the early detection of abnormalities in fetal cerebral blood flow, especially in fetal anemia secondary to hemoglobin Bart's disease.

Prediction of severe fetal anemia in red blood cell alloimmunization after previous intrauterine transfusions

OBJECTIVE

This study was undertaken to determine the detection of fetal anemia and false-positive rates by fetal middle cerebral artery peak systolic velocity (MCA-PSV) and the estimated daily decrease of hemoglobin (Hb) in red blood cell alloimmunized pregnancies that had previous fetal transfusions.

STUDY DESIGN

We examined the relation between MCA-PSV measured before cordocentesis, and fetal Hb at the time of the second (n = 42) and third (n = 31) intrauterine blood transfusions. In addition, the daily Hb drop between the transfusions was calculated.

RESULTS

The MCA-PSV provided significant prediction of severe anemia (Hb deficit > or = 6 g/dL) for the second but not for the third transfusion. Detection of 95% of severely anemic fetuses was achieved with a false-positive rate of 37% for the second transfusion and 90% for the third, compared with 14% in our previous study for the first transfusion. In patients who had received 2 previous transfusions, the only significant predictor of fetal anemia was the estimation of the Hb from the measured posttransfusion Hb after the second transfusion and the assumption that the rate of decrease in fetal Hb is 0.3 g/dL per day.

CONCLUSION

Prediction of severe fetal anemia after one transfusion is less accurate than in nontransfused fetuses. The MCA-PSV is not useful in predicting severe anemia in fetuses that already had 2 previous transfusions.

Serial blood donations for intrauterine transfusions of severe hemolytic disease of the newborn with the use of recombinant erythropoietin in a pregnant woman alloimmunized with anti-Ku

BACKGROUND

The management of a pregnant woman with the rare Ko phenotype and anti-Ku is a special challenge, because matched blood is extremely rare and the possibility of severe hemolytic disease of the newborn is high.

CASE REPORT

A 30-year-old woman with rare Ko (Knull) phenotype presented at 18 weeks of gestation with positive indirect agglutination test results. She had anti-Ku due to previous blood transfusion, one pregnancy, and two abortions.

STUDY DESIGN AND METHODS

During this pregnancy, anti-Ku titers ranged from 1024 to 4096. At the 26th week of gestation ultrasound showed a hydropic fetus and urgent intrauterine exchange transfusion was performed with the maternal red blood cells (RBCs). Recombinant human erythropoietin (rHu-EPO) and intravenous (IV) iron were administered to the mother to ensure an adequate supply of matched RBCs for intrauterine transfusions and possible perinatal hemorrhage.

RESULTS

Intrauterine transfusions were repeated every 1 to 3 weeks. By 35 weeks 2 days of gestation, the mother had donated 4 units of blood, and four intrauterine transfusions had been performed. Cesarean section was then decided and a healthy male newborn was born. He was treated with phototherapy but without exchange transfusions. By the 15th day of life rHu-EPO was administrated to the newborn because of anemia. The maternal RBCs completely disappeared from the child's blood by Day 100.

CONCLUSIONS

As shown in this case, treatment with rHu-EPO and IV Fe has effectively increased the mother's capacity to donate RBCs for autologous use and intrauterine transfusions, with no adverse effects to the mother or the child.

Middle cerebral artery peak systolic velocity: is it the standard of care for the diagnosis of fetal anemia?

OBJECTIVE

The aim of this work was to review the use of middle cerebral artery peak systolic velocity (MCA PSV) for the diagnosis of fetal anemia.

METHODS

With the use of a computerized database (MEDLINE), articles on the diagnosis of fetal anemia with ultrasonography were reviewed. Other pertinent references were obtained from the references cited in these articles. In addition, my own institution's clinical experience of the past 18 years was reviewed.

RESULTS

Several ultrasonographic parameters have been used to diagnose noninvasive fetal anemia. On the basis of robust data, the MCA PSV is the best ultrasonographic parameter used in the management of fetuses at risk for anemia due to different causes. It is also superior to amniocentesis for the diagnosis of fetal anemia in cases of red cell alloimmunization.

CONCLUSIONS

Middle cerebral artery peak systolic velocity is effective for diagnosis of noninvasive moderate and severe fetal anemia. This parameter should not yet be considered the global standard of care for diagnosis of fetal anemia because incorrect use by an inexperienced operator may cause more harm than good; however, if there is a reasonably close medical center with sonographers or sonologists trained to assess the MCA PSV, patients at risk for fetal anemia should be referred to this center.

Comparison of different reference values of fetal blood flow velocity in the middle cerebral artery for predicting fetal anemia

OBJECTIVES

To compare different normal reference ranges of fetal blood flow velocity in the middle cerebral artery for predicting fetal anemia.

METHODS

Eight reference ranges of either middle cerebral artery peak or time-averaged mean velocities were compared using the area under the receiver-operating characteristics (ROC) curve for 113 fetal blood samples from 60 women at risk of fetal red blood cell alloimmunization.

RESULTS

The areas under the ROC curves of the different ranges were not significantly different but there were marked differences in sensitivity (range, 7.14-91.78%) and specificity (range, 31.25-96.88%) with the currently used cut-offs. Except for Mari's range, the best theoretical cut-offs, defined as those having the best sensitivity with the best specificity, differed from those in current use, especially when using time-averaged mean velocity.

CONCLUSIONS

Any of the previously reported reference ranges perform well in the non-invasive prediction of fetal anemia. However, with the exception of Mari's curve, the currently employed cut-offs for predicting fetal anemia should be changed, some of them markedly, in order to provide reliable support for clinical decisions.

Diagnosis, surveillance, and treatment of the anemic fetus using middle cerebral artery peak systolic velocity measurement

The in utero course of the anemic fetus has improved dramatically, owing to early diagnosis and cordocentesis transfusion. In utero invasive procedures such as amnio- and cordocentesis have become important modalities in the evaluation and treatment of anemic fetuses. However, they carry risks for both the mother and fetus. A valid and sensitive noninvasive means of following the anemic fetus is the evaluation of changes in the middle cerebral artery peak systolic flow velocity (MCA-PSV). This is a sensitive tool for both the evaluation of fetal anemia and response to treatment. Intracerebral vessels respond earliest to the fetal anemic state, and are readily accessible for ultrasound examination. We describe the methodology and evolving clinical applications of MCA-PSV measurement in the fetus, through an overview of the literature describing the development and application of MCA-PSV measurement in fetuses at risk of fetal anemia of various immune and nonimmune etiologies, illustrated by index cases from our center. MCA-PSV measurement is essential in the diagnosis, evaluation, and management of cases of fetal anemia. The use of this modality lessens the need for invasive procedures. The method is readily accessible and should be integrated into the repertoire of all obstetric ultrasound centers.

Fetal middle cerebral artery peak systolic velocity in the investigation of non-immune hydrops

OBJECTIVE

In some cases of non-immune hydrops there is congenital or acquired fetal anemia. The aim of this study was to investigate the potential value of fetal middle cerebral artery peak systolic velocity (MCA-PSV) in the assessment and management of non-immune hydrops due to anemia.

METHODS

Fetal MCA-PSV and fetal hemoglobin concentration, in blood obtained by cordocentesis, were measured in 16 singleton pregnancies referred to our unit for further investigations because of a diagnosis of non-immune hydrops fetalis. In all cases a detailed ultrasound examination demonstrated moderate or severe ascites, with or without skin edema, and pericardial or pleural effusions. Furthermore, there were no obvious malformations to account for the hydrops. In each fetus the measured MCA-PSV and hemoglobin concentration were expressed as delta values (the difference in SD from the normal mean for gestation). Regression analysis was used to determine the significance of the association between delta MCA-PSV and delta fetal hemoglobin concentration. In addition, we searched our database to identify the sonographic features and hemoglobin concentration of fetuses with congenital infection.

RESULTS

In the 16 cases of non-immune hydrops there were seven with parvovirus B19 infection, one each of alpha-thalassemia and primary cardiomyopathy and seven with no obvious explanation for the hydrops. There was a significant association between delta MCA-PSV and delta hemoglobin concentration (delta hemoglobin = (delta MCA-PSV + 0.1437)/-0.4154; R(2) = 0.7202; P < 0.0001). In 10 of the cases the fetal hemoglobin concentration was more than 4 SD below the normal mean for gestation and in all these cases the MCA-PSV was more than 2 SD above the normal mean for gestation. Our computer search identified an additional nine fetuses with parvovirus B19 infection and in all cases the predominant sonographic finding was ascites and the hemoglobin concentration was more than 4 SD below the normal mean. In contrast, only 3/14 fetuses with cytomegalovirus, toxoplasmosis, coxsackie B or Treponema infection had ascites and only 2/14 had a hemoglobin deficit of 4-6 SD.

CONCLUSION

In the management of non-immune hydrops, measurement of fetal MCA-PSV can help identify the subgroup with fetal anemia.