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PubMed1996

Management of diabetic pregnancy complicated by coronary artery disease and neuropathy.

Various manifestations of diabetic neuropathy may complicate pregnancies of young diabetic patients. Of all forms of diabetic neuropathy, autonomic neuropathy, and, in particular, gastropathy, may cause the most devastating complications. Because neuropathy is a common abnormality in young asymptomatic diabetic women, screening for this disorder may be advisable and can be accomplished by relatively simple and noninvasive tests. Screening is best performed before conception or early in pregnancy, because pregnancy itself and its possible complications later modify the autonomic nervous function tests and make testing unreliable. Practitioners and obstetricians who provide care and counseling to young diabetic patients should be familiar with the risks and consequences to maternal and fetal health that may be imposed by the different forms of neuropathy. Moderate-to-severe autonomic dysfunction may be considered a relative contraindication to pregnancy, especially if gastropathy is part of the clinical presentation. The management dilemmas and high mortality and morbidity associated with symptomatic diabetic neuropathy may justify the addition of a new independent class, class N (neuropathy), to the current classification systems for diabetes in pregnancy.

Autonomic Nervous System Diseases↗
PubMed1988

The use of Doppler waveform analysis in the evaluation of the high-risk fetus.

The development of Doppler ultrasound evaluation of the uteroplacental and fetoplacental circulations is one of the most important achievements of modern obstetrics. For the first time, the obstetrician has the ability to evaluate, in a noninvasive way, circulatory systems critical to fetal development and the outcome of pregnancy and to obtain information of great value for the management of complicated pregnancies. At this time, Doppler examination of the umbilical artery has become a fundamental part of the evaluation of pregnancies complicated by retarded fetal growth. Doppler examination of the umbilical and uterine arteries has become the most accurate test to establish a fetal prognosis in patients with hypertension in pregnancy. Other indications for the use of this methodology (twins, diabetes, Rh isoimmunization, etc.) are being studied, and the role of Doppler ultrasound probably will extend significantly beyond the now well-established indications for its use.

Blood Flow Velocity↗
PubMed2003

Effectiveness of pulse oximetry screening for congenital heart disease in asymptomatic newborns.

OBJECTIVE: To determine the sensitivity, specificity, predictive value, and accuracy of a program of pulse oximetry screening of asymptomatic newborns for critical congenital cardiovascular malformation (CCVM). METHODS: Pulse oximetry was performed on asymptomatic newborns in the well-infant nurseries of 2 hospitals. Cardiac ultrasound was performed on infants with positive screens (saturation 24 hours). Data regarding true and false positives as well as negatives were collected and analyzed. RESULTS: Oximetry was performed on 11 281 asymptomatic newborns, and 3 cases of CCVM were detected (total anomalous pulmonary venous return x2, truncus arteriosus). During the study interval, there were 9 live births of infants with CCVM from a group of 15 fetuses with CCVM detected by fetal echocardiography. Six infants with CCVM were symptomatic before screening. There was 1 false-positive screen. Two infants with negative screens were readmitted (coarctation, hypoplastic left pulmonary artery with aorto-pulmonary collaterals). Other cardiac diagnoses in the database search were nonurgent, including cases of patent foramen ovale, peripheral pulmonic stenosis, and ventricular septal defect. The prevalence of critical CCVM among all live births was 1 in 564 and among the screened population was 1 in 2256 (sensitivity: 60%; specificity: 99.95%; positive predictive value: 75%; negative predictive value: 99.98%; accuracy: 99.97%). CONCLUSIONS: This screening test is simple, noninvasive, and inexpensive and can be administered in conjunction with state-mandated screening. The false-negative screen patients had lesions not amenable to detection by oximetry. The sensitivity, specificity, and predictive value in this population are satisfactory, indicating that screening should be applied to larger populations, particularly where lower rates of fetal detection result in increased CCVM prevalence in asymptomatic newborns.

Evaluation Studies as Topic↗
PubMedDate not supplied

Applicability of four new antibodies for the detection of fetal nucleated cells out of maternal blood by FISH analysis.

The availability of fetal cells from the maternal peripheral blood opens up the possibility for a noninvasive prenatal diagnosis. Until now this prospect has been hampered by the fact that there are no highly specific antibodies to fetal cells. In the present study, four as yet untested monoclonal antibodies - 2G5, 3F9, EPO-R and Flk1 - were analyzed in view of their effectiveness to stain fetal nucleated cells. Therefore, 20 ml of peripheral blood from 40 women carrying a male fetus were collected in the 16th to 28th weeks of pregnancy. Mononucleated cells, enriched by density gradient, were stained with one of the four antibodies and isolated with magnetic cell sorting. Subsequently, fluorescence in situ hybridization with chromosome X and Y centromere probes was performed which allowed us to analyze the maternal or fetal origin of the enriched cells. For evaluation, 500 nuclei per case were examined. The antibody 3F9 detected 0.2 cells on average (n = 5), 2G5 1.2 (n = 11), EPO-R 1.6 (n = 10) and Flk1 1.8 cells (n = 8) with fetal specific Y-positive hybridization signals. The antibody against CD71 (n = 6) used as control gave no Y-specific signals. Considering these results, the tested antibodies, especially Flk1, appear to be more successful in detecting fetal cells than the commonly used CD71 antibody.

Antibodies, Monoclonal↗
PubMed1998

The routine obstetric ultrasound examination.

Ultrasound is a readily available, noninvasive, and safe means of evaluating fetal health, determining gestational age, and assessing the intrauterine environment. It is an indispensable tool for the practice of obstetrics. The routine ultrasound examination is a beginning. It is a diagnostic test, yielding results that must be interpreted and integrated in a knowledgeable way. As is true for physical examination, the ultrasound study is most helpful when performed in a consistent and reproducible fashion, carefully documenting the pertinent positive and negative findings that are important in clinical decision making. The information gained from routine obstetric ultrasound may provide reassurance, guide therapy, or identify a pathologic condition that merits further investigation. It is always informative.

Diagnostic Tests, Routine↗
PubMed2004

Use of maternal plasma for noninvasive determination of fetal RhD status.

Determination of the fetal RhD typing using free fetal DNA in maternal plasma is beginning to enjoy widespread acceptance in Europe. Case 1, the partner of an RhD-sensitized patient, was identified with a heterozygous paternal phenotype by serologic testing. Maternal plasma was drawn at 18 weeks' gestation to determine the fetal RhD status. The result was unable to be reported as RhD negative; the patient subsequently underwent amniocentesis to confirm an RhD-negative fetus. Case 2, a partner of another RhD-sensitized patient, was similarly identified with a heterozygous paternal phenotype by serologic testing. Maternal plasma was also drawn at 18 weeks' gestation to determine the fetal RhD status. It returned RhD negative and allowed for the avoidance of invasive testing for the remainder of the pregnancy. Therefore, maternal plasma testing for fetal RhD status represents a new tool in the management of the cases of RhD alloimmunization in pregnancy.

Adult↗
PubMed2003

Noninvasive tests to predict fetal anemia: a study comparing Doppler and ultrasound parameters.

OBJECTIVE: This study was undertaken to compare test characteristics of ultrasound and Doppler parameters in the prediction of fetal anemia in alloimmunized pregnancies. STUDY DESIGN: In a prospective cohort study, 16 nonhydropic fetuses with red blood cell alloimmunization were evaluated with ultrasound and Doppler imaging. Middle cerebral artery (MCA) peak systolic velocity, intrahepatic umbilical venous (IHUV) maximum velocity, liver length, and spleen perimeter were measured. Results before first fetal blood sampling (FBS) or delivery were analyzed. Fetal anemia was defined as hemoglobin deficit 5 SD or greater. Sensitivity and specificity were calculated. RESULTS: Six fetuses were anemic and required intrauterine transfusion, and 10 were not severely anemic at birth. MCA Doppler imaging was the best predictor of fetal anemia (100%), followed by IHUV (83%). Sensitivity was low for spleen perimeter (66%) and liver length (33%). CONCLUSION: Doppler evaluation of MCA peak systolic velocity is better than IHUV maximum velocity, liver, or spleen size in the prediction of fetal anemia in red blood cell alloimmunization.

Blood Transfusion, Intrauterine↗
PubMed1987

Prenatal diagnosis and screening.

We have limited the scope of this article to those disorders that have already been successfully diagnosed or excluded in utero. We currently have the potential to diagnose a number of others for which the opportunity has not yet arisen. If a biochemical, morphologic, chromosomal, or DNA alteration is known for a specific condition and is likely to be expressed in one of the fetal tissues or secretions, attempt at prenatal diagnosis is reasonable. Our ability to detect the inherited disorders of the skin in utero will continue to improve both in the number of specific disorders successfully diagnosed or excluded and in the increasingly earlier stages of pregnancy at which the disorder can be detected. Advances in instrumentation will, it is hoped, decrease the risk of the invasive methods of prenatal diagnosis, and improvement in noninvasive methods, such as maternal serum screening, may eliminate the need for invasive procedures altogether. Detection of useful DNA polymorphisms linked to genes for specific genodermatoses and development of specific gene probes will improve the accuracy of diagnosis and reduce the need for specific fetal tissues. The entire genome of an individual is present in each cell, even though a specific gene product may not be expressed in that cell. Thus, DNA restriction endonuclease studies can be performed on amniotic fluid cells, chorionic villi, fetal cells in maternal circulation, and fetal tissues with equal facility. The usefulness of prenatal diagnosis will always be limited by the ability to detect pregnancies at risk. If carrier detection is unavailable, the only way to identify couples at risk for offspring with an autosomal recessive condition is by the birth of an affected child. For autosomal dominant and X-linked recessive and dominant conditions, new mutations will continue to occur. As mentioned previously, screening of all pregnancies for all defects is not possible now and is unlikely ever to be feasible, either economically or technically. The reliability of prenatal diagnosis will continue to depend upon accurate diagnosis in the index case and upon the availability of a specific and sensitive test (or tests), with no overlap in values between heterozygotes and homozygotes for autosomal recessive conditions or between normal and affected fetuses with autosomal dominant and X-linked recessive disorders. Correct interpretation of test results is subject to experience, recognition of artifact, and variation in the expression of a given disorder in utero.(ABSTRACT TRUNCATED AT 400 WORDS)

Amniocentesis↗
PubMedDate not supplied

Fetal rhd genotyping from maternal plasma in a population with a highly diverse ethnic background.

OBJECTIVE: To establish the performance of conventional PCR as a noninvasive method for fetal genotyping, by free fetal DNA analysis of distinct RHD regions from maternal plasma, in a population of a diverse ethnic origin. METHODS: We conducted a validity of the diagnostic test by analyzing 81 plasma samples from RhD-negative Brazilian pregnant women, from 4 to 41 gestational weeks. We tested for exon 10 and intron 4 gene regions by allele specific-PCR. Fetal RHD genotyping by PCR on maternal plasma was compared to serologic RhD typing in the neonatal period. RESULTS: Samples were obtained as follows: 15 in the 1st, 37 in the 2nd and 29 in the 3rd trimester. General accuracy was 97.3%, sensitivity of 98.3% and specificity of 93.8%. CONCLUSIONS: Conventional PCR is an accurate method for fetal RHD genotyping on maternal plasma, even in a population of mixed ethnic origin.

Brazil↗
PubMed1978

Antepartum evaluation of the pre-ejection period of the fetal cardiac cycle.

The pre-ejection period (PEP) of the cardiac cycle was studied in 65 antepartum fetuses by means of a noninvasive technique which used simultaneous recordings of abdominal fetal electrocardiogram (FECG) and ultrasound fetal Doppler cardiogram (FDCG). Although most of the fetuses were products of high-risk pregnancies, 45 fetuses had uneventful perinatal courses. The PEP's from these fetuses demonstrated a significant positive relationship with gestational age (p is less than 0.01). Uterine contractions induced for antepartum stress testing of the fetus were founnd to prolong the PEP by approximately 9.1 per cent in five cases (four fetuses). The average PEP of antepartum fetuses between 38 and 40 weeks was shorter than that of intrapartum fetuses by approximately 9.5 per cent. Comparison between clinical outcome and the PEP's of the fetuses who were born within a week after the last determination of PEP revealed a strong correlation between prolonged PEP duration and abnormalities in the perinatal course.

Electrocardiography↗
PubMed2005

Magnetocardiograms in clinical medicine: unique information on cardiac ischemia, arrhythmias, and fetal diagnosis.

Cardiac diseases are the leading cause of death in population. Diagnostic tests to detect cardiac dysfunction at an early stage of the disease are desirable. The major focus has been centered on tests evaluating the perfusion of the heart with imaging techniques or detecting alterations in electrical or mechanical function of the heart. The heart generates magnetic fields that can be detected by body surface mapping utilizing super conducting quantum interference device sensors giving magnetocardiograms (MCGs). The advantages of MCG over traditional electrocardiograms (ECGs) are increased sensitivity to small signals and lack of conductivity in body tissues, presentation of direct component signals and primary currents. This review will highlight the basic principles and recent advantages of MCGs, and the application of MCG in clinical diagnosis, especially in cases whose ECGs are non-diagnostic or not specific, such as detecting baseline shift in ischemic heart disease, noninvasive His potential recording, detection of arrhythmic mechanism defining reentrant circuits vs non reentrant mechanism, diagnosis of fetal arrhythmias and prolongation of QT interval. Areas of future basic and clinical research are also discussed.

Arrhythmias, Cardiac↗
PubMed1998

[Tri-test: clinical considerations on 1784 cases].

BACKGROUND: To evaluate the triple screen serum test as a noninvasive screening test for expectant mothers > 35 years old, who are not usually considered for invasive screening for trisomy 21. METHODS: 1784 tri-tests (triple serum screening tests) were performed on expectant mothers between their 15th and 18th week of pregnancy, using the radioimmunological Ria-Kodak with an Alpha program (Logical Medical System LTD) with a cut-off value of 1:350. RESULTS: 244 positive equal to 13.60%. The percentage of false positives was respectively 12.9% (age < 35) and 28% (age > 35). Only in two of these cases did we have a positive response in amniocentesis for a fetus affected with Down syndrome. Of the 1540 patients with a negative tri-test, one woman gave birth to a fetus with Down syndrome. CONCLUSIONS: Our study revealed a sensitivity of 66%. The elevated number of false positives has led us to decide on a variation on the cut off in the future: from 1:350 to 1:300.

Chorionic Gonadotropin↗
PubMed1993

Prediction of cerebral palsy in high-risk neonates: a technetium-99m-HMPAO SPECT study.

In infants who have experienced prenatal or perinatal injury, it is often difficult, on the basis of clinical examination and conventional investigations (electroencephalogram, cranial ultrasound scan), to diagnose those with brain damage and to predict the type and the severity of subsequent neurological handicaps. We investigated the predictive value of 99mTc-HMPAO brain SPECT performed in the first weeks of life in high-risk neonates. Right-left asymmetries in tracer uptake had no predictive value, regardless of their localization or severity. On the other hand, a change in antero-posterior rCBF distribution was found in 7/10 of neonates with adverse outcome (death, major neurological sequelae) and in none of the 78 neonates with no major motor neurological sequelae. Compared to conventional investigations, 99mTc-HMPAO brain SPECT did not provide additional predictive information when neurological examination, electroencephalogram and cranial ultrasonography were all normal or all abnormal. Conversely, in the 30 patients with anomalies on one or two of the above investigations, SPECT showed an abnormal antero-posterior pattern in 4/6 neonates with major neurological sequelae and no change in the antero-posterior rCBF distribution in the 24 infants who developed normally. In conclusion, our results suggest that 99mTc-HMPAO brain SPECT, when performed in the first weeks of life, can be useful in high-risk neonates to predict occurrence of major neurological handicaps. Because of the relative invasive character of HMPAO scan in neonates and the overall accuracy of the noninvasive tests, radionuclide examination should not be performed in every high-risk neonate. According to our results, 99mTc-HMPAO brain SPECT might be indicated in those children where noncongruent results were obtained with conventional studies.

Cerebral Palsy↗
PubMed2002

Isolation of fetal nucleated red blood cells from maternal blood in normal and aneuploid pregnancies.

Fetal nucleated red blood cells (NRBC) have been widely reported in maternal blood during pregnancy. However, there is no consensus with regard to their presence in all pregnancies. Therefore, the usefulness of developing a fetal NRBC-based noninvasive method suitable for clinical prenatal diagnosis remains uncertain. Fluorescence in situ hybridization (FISH) method was used to evaluate the ability of one of our own monoclonal antibodies (mAb), 2B7.4, to isolate fetal NRBC from maternal blood by magnetic activated cell sorting (MACS). Our mAb was able to isolate from 25 to 822 NRBC from all of the 45 maternal blood samples included in this study. A correct diagnosis was achieved in 21 out of 24 pregnancies carrying trisomic fetuses (87.5%), with a fetal/maternal NRBC frequency of 8.4%. In contrast, a significantly lower percentage of fetal NRBC (0.2%) was observed in 22% of pregnancies carrying a chromosomally normal male fetus, that were correctly predicted. In conclusion, using 2B7.4 mAb we succeeded in isolating NRBC from the maternal blood samples, but most of the isolated cells were maternal in origin. Nevertheless, a higher number of fetal NRBC was found in the peripheral blood of pregnant women carrying aneuploid fetuses, which could allow development of a screening method for prenatal diagnosis of fetal aneuploidies.

Aneuploidy↗
PubMed2006

Urine interleukin-8 as a marker of vesicoureteral reflux in infants.

OBJECTIVE: Vesicoureteral reflux (VUR) is a common finding in children presenting with urinary tract infection (UTI) and prenatally diagnosed urinary tract dilatation and in relatives of index patients. Children with VUR are at risk for ongoing renal damage with subsequent infections. Detecting VUR and renal scarring currently depends on imaging modalities with associated problems of radiation, invasiveness, and expense. Noninvasive methods would greatly facilitate diagnosis and would also help in identifying relatives of index cases who should be screened. Interleukin-8 (IL-8) is produced by epithelial cells of the renal tract in response to inflammatory stimuli and has been shown to increase during acute UTI. The objective of this study was to assess the urine levels of IL-8 as a noninvasive marker of VUR in infants in the absence of a recent UTI episode. METHODS: We evaluated urine concentrations of IL-8 in 59 infants aged 1 month to 2 years. All infants were free of UTI for a minimum of 3 weeks before IL-8 evaluation. Infants were divided into 3 groups: group A, subjects with proven VUR (24 infants aged 0.15-1.95 years, median 0.43); group B, subjects with a history of UTI but negative investigation for VUR (14 infants aged 0.32-1.95 years, median 0.57); and group C, subjects without any history of acute or chronic condition that might impair renal function (21 infants aged 0.08-1.92 years, median 0.33). IL-8 concentrations were determined by a commercially available quantitative enzyme-linked immunosorbent assay. To avoid dilution effects, urinary levels of IL-8 were expressed as the ratio of cytokine-to-urinary creatinine. RESULTS: Results were presented as medians and ranges. The Kruskal-Wallis test, the Mann-Whitney rank sum U test, and the Spearman rank order correlation test were performed for the univariate analysis. Two-tailed P values were calculated and the conventional level of significance P < .05 was applied in all cases. Infants in groups A and B had been free of UTI for a period of 3 to 52 weeks (median, 5.0 weeks) and 3 to 78 weeks (median, 4.5 weeks), respectively, before IL-8 determination. No significant difference was noted in the length of the UTI-free period between groups A and B (P = .469). Urine creatinine concentrations did not differ among groups A, B, and C (medians 1.15, 2.25, and 1.15 micromol/mL, respectively; P = .080). The median urine IL-8/creatinine concentrations (pg/micromol) were 40.5 (range, 2.04-3874) in group A, 1.91 (range, 0.001-386) in group B, and 2.47 (range, 0.002-55.6) in group C. Urine IL-8/creatinine concentrations were significantly higher in group A than both in group B (P = .0003) and in group C (P < .0001). No significant difference was observed between groups B and C (P = .749). In group A, no significant correlation was shown between IL-8/creatinine concentrations and the presence of renal parenchymal damage (P = .506), reflux grade (P = .770), or time from UTI (P = .155). A receiver-operator characteristic curve was constructed by plotting the sensitivity versus the specificity for different cutoff concentrations of IL-8/creatinine. With a cutoff concentration of urinary IL-8/creatinine at 5 pg/micromol, the sensitivity of this marker in diagnosing VUR was 88%, the specificity 69%, the positive prognostic value 66%, and the negative prognostic value 89%. In higher cutoff concentrations, specificity of the marker increased but sensitivity rapidly decreased. CONCLUSIONS: We present evidence that urine IL-8 concentrations remain elevated in infants with VUR even in the absence of UTI and that a cutoff of 5 pg/micromol IL-8/creatinine is of high sensitivity and adequate specificity for diagnosing VUR. Elevated urine IL-8 levels in VUR and renal scarring have already been reported; however, the present study is, to our knowledge, the first to confirm significant differences between infants with VUR and infants with a history of UTI alone and healthy controls, and to suggest a reliable cutoff concentration for diagnosing VUR. Our findings additionally suggest that inflammatory process in VUR is ongoing even after UTI has resolved, pointing against the currently held belief that sterile reflux cannot harm kidneys. The chronic inflammatory cell infiltrate associated with reflux nephropathy rather than VUR itself might offer an explanation for the secretion of IL-8, which may well be independent of reflux grade. Using urine IL-8 for diagnosing VUR is not free of limitations, because IL-8 may be elevated as a result of urinary tract manipulation or undetected UTI. In addition, this study focused on infants and not in older children with longstanding VUR. Increased urine IL-8 concentrations after UTI has resolved is a promising noninvasive marker for an initial screening for VUR in infancy with high sensitivity and adequate specificity.

Biomarkers↗
PubMed1998

Fetal cell detection in maternal blood: a study in 236 samples using erythroblast morphology, DAB and HbF staining, and FISH analysis.

A protocol to detect fetal nucleated red blood cells (NRBCs) was tested in 217 pregnant women and in 19 nonpregnant controls. All the pregnant women were sampled after chorionic villus sampling (CVS); 20 were also sampled pre-CVS. NRBC recognition was based upon morphology by using staining of hemoglobin with 3,3-diaminobenzidin (DAB) or by immunocytochemical staining for fetal hemoglobin (HbF). This was combined with FISH analysis for both the X- and Y-chromosomes on the same cells. Progressive refinement of the methods increased the number of cases where NRBCs were detected from 53% (DAB) to 75% and 78% for DAB and HbF staining, respectively, with on average 43 NRBCs (range, 1-220). DAB gave a slightly higher yield than HbF in the lower cell count range (<25). In 6 out of 18 controls, NRBCs were detected with DAB, vs. 1 out of 19 (5%) with HbF. FISH analysis in 41 cases resulted in correct sex prediction in 80% (DAB) and 89% (HbF), respectively. Our data demonstrated an increase of cases with NRBCs (30% to 75%), as well as a rise of the mean number of NRBCs (6 to 29 cells), after CVS. We conclude that DAB staining is a straightforward way to screen for the presence of NRBCs in maternal blood, but is not specific for NRBCs of fetal origin. HbF immunophenotyping is a reliable marker for fetal NRBCs, which detected slightly fewer NRBCs than DAB-staining, but improved sex prediction and significantly reduced false-positive results. CVS at 10-13 weeks of gestation causes a significant increase of NRBCs in maternal blood. These data indicate that further refinement of NRBC detection is needed before application of noninvasive prenatal diagnosis using maternal blood is feasible.

Chorionic Villi Sampling↗
PubMed2007

Doppler ultrasound in mice.

Color, power, spectral, and tissue Doppler have been applied to mice. Due to the noninvasive nature of the technique, serial intraindividual Doppler measurements of cardiovascular function are feasible in wild-type and genetically altered mice before and after microsurgical procedures or to follow age-related changes. Fifty-megahertz ultrasound biomicroscopy allows to record the first beats of the embryonic mouse heart at somite stage 5, and the first Doppler-flow signals can be recorded after the onset of intrauterine cardiovascular function at somite stage 7. Using 10- to 20-MHz ultrasound transducers in the mouse embryo, cardiac, and circulatory function can be studied as early as 7.5 days after postcoital mucous plug. Postnatal Doppler ultrasound examinations in mice are possible from birth to senescent age. Several strain-, age-, and gender-related differences of Doppler ultrasound findings have been reported in mice. Results of Doppler examinations are influenced by the experimental settings as stress testing or different forms of anesthesia. This review summarizes the present status of Doppler ultrasound examinations in mice and animal handling in the framework of a comprehensive phenotype characterization of cardiac contractile and circulatory function.

Age Factors↗
PubMed2001

Detection of fetal erythroid cells from maternal blood using fluorescence in situ hybridization and liquid culture.

Fetal nucleated erythrocytes circulating in maternal blood are a potential source of fetal DNA for noninvasive prenatal genetic diagnosis. However, the estimated ratio of fetal to maternal cells is extremely small. In order to enrich these cells, we performed direct culture using a two-phase liquid system. Mononuclear cells were obtained from maternal blood samples at 8-10(+3) weeks of gestation and cultured in the first phase. After 4-5 days, the nonadherent cells were harvested and recultured with erythropoietin in the second phase for another 3-5 days. We examined cellular morphology, and counted the number of benzidine- positive cells and the percentage of glycophorin A/CD71 positive erythroid cells. We also did Kleihauer-Betke stain for Hb F, polymerase chain reaction (PCR) for SRY/DYZ1, chromosome analysis, and fluorescence in situ hybridization (FISH). The number of total erythroid cells reached about 0.1 x 10(6)-1.0 x 10(6)/mL with a purity of 84.0-97.3%. Hb F stain showed total erythroid cells of approximately 0.4 x 10(4)-9.8 x 10(4)/mL. Male DNA was detected in one case by PCR. In this case, the XY karyotype was confirmed by FISH and amniocentesis. This approach provides enriched source of fetal cells for further prenatal genetic analysis without complicated separation or sorting procedures.

Cell Culture Techniques↗