Cardiac blood flow studies in fetuses with homozygous alpha-thalassemia-1 at 12-13 weeks of gestation.
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OBJECTIVE: Fetuses affected by homozygous alpha-thalassemia-1 develop anemia as early as the first trimester. Our objective was to study hemodynamic indices in affected fetuses at 12-13 weeks of gestation to determine whether these would be useful in the prediction of anemia. DESIGN: Prospective observational study. SUBJECTS: Women referred before 14 weeks of gestation for the prenatal diagnosis of homozygous alpha-thalassemia-1. METHODS: Transabdominal and/or transvaginal Doppler sonography was performed to measure the flow velocities in the fetal ascending aorta and pulmonary artery at 12-13 weeks. The Doppler indices were compared between those that were subsequently confirmed to be affected by homozygous alpha-thalassemia-1 and those that were unaffected. RESULTS: Between June 1997 and April 1998, 60 eligible women were recruited. Doppler examination was successful in 58 fetuses. Of these, 22 were subsequently confirmed to be affected by homozygous alpha-thalassemia-1. The diagnosis was made by chorionic villus sampling and DNA analysis in two affected fetuses and by cordocentesis and hemoglobin evaluation in 20 affected fetuses. Hemoglobin concentrations could be measured in ten fetuses and these ranged from 4 to 8 g/dl. The affected fetuses had significantly higher peak velocities at the pulmonary valve and ascending aorta and a larger inner diameter of the pulmonary valve than that in unaffected fetuses. The total cardiac output was increased by one-third in affected fetuses and was mainly due to an increase of the right-side cardiac output. CONCLUSION: In the early stage of anemia, the fetus responds mainly by increasing its right-side cardiac output. However, there is extensive overlap of the values of cardiac output between the affected and the unaffected fetuses, precluding its use in the prediction of anemia. (+info)
Women's knowledge, concerns and psychological reactions before undergoing an invasive procedure for prenatal karyotyping.
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OBJECTIVES: To evaluate women's reasons for having an invasive procedure, their knowledge, how information was obtained, their satisfaction with this information, their concerns about complications and psychological reactions and distress evoked by the procedure. METHODS: Ninety-four pregnant women undergoing early amniocentesis or chorionic villus sampling (CVS) at 10-13 weeks' gestation participated in a questionnaire study. The women could choose between early amniocentesis (n = 38) and CVS (n = 31), or to be randomized to either of them (n = 25). RESULTS: Apart from two items, no differences were found between the groups. Age was the main reason for testing, and anxiety was stated as a reason by 38.3%. The women knew more about methods for fetal karyotyping, what the tests can reveal and how they are performed, than about the risks and reliability of the tests. The main source of information had been doctors and midwives at the antenatal care center. For a majority of women (64.9%) the decision to have the test was made together with their partner. The women's concerns were focused on worry about fetal injury, miscarriage and waiting for the result. The test did not have a major psychological impact on the women in general, but a substantial minority reacted with anxiety and distress. CONCLUSIONS: Knowledge of factors important to women and their concerns is essential for professionals working with genetic counselling and performance of invasive procedures. (+info)
Studies of the mechanism of amniotic sac puncture-induced limb abnormalities in mice.
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The principal advantage of chorionic villus sampling (cvs) over amniocentesis for the determination of the genetic constitution of the embryo is that it may be undertaken earlier in pregnancy. If carried out too early in pregnancy, it has the risk of inducing craniofacial and limb abnormalities, a condition termed the oromandibulofacial limb hypogenesis (OMFL) syndrome in genetically normal infants. It is believed that the defects observed have a vascular origin, possibly due to anoxia of tissues due to fetal blood loss or thrombus formation at the site of biopsy with distal embolization. We believe that this does not adequately explain the findings from the experimental animal literature involving amniotic sac puncture (ASP). Based on these experimental findings, we have hypothesised that (i) the defects observed following cvs may result from the consequences of oligohydramnios following the inadvertent puncturing of the amniotic sac during this procedure, and (ii) that cleft palate and the postural limb defects observed (e.g., clubfoot and clubhand) are secondary to embryonic/fetal compression. Our experimental studies shed new light on the mechanism of induction of the limb defects seen, but particularly syndactyly. Evidence of hypoperfusion of the peripheral part of the developing limb bud is observed, which interferes with apoptosis that occurs in the digital interzones, or induces an abnormal degree of cellular proliferation and/or tissue regeneration in these sites, possibly because of over-expression of critical genes involved in limb pattern specification. Cleft palate, tail abnormalities and abnormalities of sternal ossification are also observed in our model. (+info)
The use of chorionic villus biopsy catheters for saline infusion sonohysterography.
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BACKGROUND: Saline infusion sonohysterography is one of the recent refinements of ultrasonography that has the ability to enhance imaging of the uterine cavity in a safe, inexpensive and expedient manner. The technique can be difficult in women with a stenotic cervical os. This report describes a single-pass technique using chorionic villus sampling (CVS) catheters for saline infusion sonohysterography. METHOD: Saline infusion sonohysterography requires the transcervical passage of a catheter, through which saline is infused. The subsequent distension of the uterine cavity enhances the ability to detect intrauterine pathology with ultrasonography. In women with cervical stenosis, a catheter can be used in place of the more conventional two-pass technique, which requires the use of a uterine sound or probe followed by a conventional catheter. EXPERIENCE: We have used CVS catheters in women with cervical stenosis on 12 occasions. All have been successful and without significant discomfort to the patient. CONCLUSION: The use of CVS catheters for saline infusion sonohysterography in women with cervical stenosis can alleviate the need to remove the cervical probe prior to introduction of the catheter. (+info)
The impact of placental malaria on gestational age and birth weight.
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Maternal malaria is associated with reduced birth weight, which is thought to be effected through placental insufficiency, which leads to intrauterine growth retardation (IUGR). The impact of malaria on preterm delivery is unclear. The effects of placental malaria-related changes on birth weight and gestational age were studied in 1177 mothers (and their newborns) from Tanzania. Evidence of malaria infection was found in 75.5% of placental samples. Only massive mononuclear intervillous inflammatory infiltration (MMI) was associated with increased risk of low birth weight (odds ratio inverted question markOR, 4.0). Maternal parasitized red blood cells and perivillous fibrin deposition both were associated independently with increased risk of premature delivery (OR, 3.2; OR, 2.1, respectively). MMI is an important mechanism in the pathogenesis of IUGR in malaria-infected placentas. This study also shows that placental malaria causes prematurity even in high-transmission areas. The impact of maternal malaria on infant mortality may be greater than was thought previously. (+info)
Prenatal diagnosis of beta-thalassaemia using fetal erythroblasts enriched from maternal blood by a novel gradient.
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We have assessed a new technique for the isolation of fetal erythroblasts from maternal blood for the non-invasive prenatal diagnosis of pregnancies at risk of beta-thalassaemia. This method relies on the separation of erythroblasts from maternal nucleated cells by a novel step gradient and high speed centrifugation. In four of the six cases examined, single erythroblasts were identified by immunohistochemistry for zeta (zeta) globin. These were individually micromanipulated and analysed by single cell polymerase chain reaction (PCR) and subsequent sequencing of the region of beta-globin locus where the mutations most common to the region of Puglia, Italy, are clustered. In each of the four instances where fetal erythroblasts were identified by antibody staining, the fetal beta-globin genotype was correctly determined. To date, this represents the largest series of non-invasive prenatal diagnoses performed for this haemoglobinopathy. (+info)
Maternal uniparental heterodisomy of chromosome 14: chromosomal mechanism and clinical follow up.
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To our knowledge, 22 cases of chromosome 14 maternal uniparental disomy (UPD(14)mat) have been reported so far. The majority of cases were ascertained because of an abnormal phenotype associated with a Robertsonian translocation involving chromosome 14. We report here on a child with UPD(14)mat detected prenatally and resulting from trisomy rescue in a maternal meiosis I non-disjunction trisomic zygote. After four years of clinical follow up, in addition to intrauterine growth retardation (IUGR), only short stature and small hands and feet were observed. These clinical data as well as the ascertainment and mechanism of origin of UPD(14)mat were compared with those observed in previously reported cases. It appears that the clinical spectrum of UPD(14)mat is milder in our patient than in patients with UPD(14)mat resulting from other chromosomal mechanisms. In addition, a hypothesis based on abnormal imprinting is proposed to explain the variability of the UPD(14)mat. (+info)
A 47,XXY fetus conceived after ICSI of spermatozoa from a patient with non-mosaic Klinefelter's syndrome: case report.
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The birth of 12 healthy infants to fathers with non-mosaic Klinefelter's syndrome has been reported so far. The spermatozoa for these pregnancies was obtained from frozen-thawed ejaculate in one pregnancy (twins) and from the testis in the remaining 10 infants. All of them had a normal karyotype. We describe a patient with non-mosaic Klinefelter's syndrome from whom a testicular biopsy was obtained and motile spermatozoa were collected. Of 16 oocytes that were injected, 14 fertilized and cleaved. Three embryos were transferred, resulting in a triplet pregnancy. Karyotype analysis from chorionic villous sampling revealed 46,XX, 46,XY and 46,XXY from the three fetuses. The affected 46,XXY fetus was reduced on the 14th gestational week. The pregnancy culminated with the birth of a healthy male and female, on the 36th gestational week, weighing 3600 and 2660 g respectively. This case report proves the presence of hyperploid spermatozoa in the seminiferous lumen, and strengthens the necessity of genetic diagnosis of the embryos or fetuses in such pregnancies to fathers with non-mosaic Klinefelter's syndrome. (+info)