Showing papers on "Amniocentesis published in 1979"

Prenatal genetic diagnosis in 3000 amniocenteses.

Abstract: We analyzed 3000 consecutive amniocenteses for prenatal diagnosis to assess the frequency of abnormalities, safety of the procedure, technical and interpretive difficulties and overall diagnostic accuracy. Chromosomal abnormalities were detected in 2.4 per cent of the 2404 pregnancies tested because of advanced maternal age (≥35 years), in 1.2 per cent of 240 monitored because of prior trisomy 21 and in 9.1 per cent of 55 examined for other cytogenetic indications. Mosaicism was detected in 0.4 per cent, and unexpected translocations in 0.4 per cent. Amniotic fluid was obtained on the first attempt in 99.3 per cent of the last 1000 cases, and cultures established from 99.7 per cent of patients attending our clinic. The fluid was discolored in 1.2 per cent of patients, a quarter of whom had missed abortions. The rate of spontaneous abortion after amniocentesis was 1.5 per cent. There were 14 diagnostic errors, six serious enough to affect the outcome of pregnancy. The karyotyping error rate was 0....

Fetal cervical teratoma as a cause of polyhydramnios

Abstract: The production and removal of amniotic fluid has been the subject of much speculation and investigation. Excessive amounts of amniotic fluid occur in less than one-half of 1% of all pregnancies and the etiology is frequently unknown.1 Fetal malformations are associated with polyhydramnios in 20% to 40% of cases.1,2 In view of this, it is important for obstetricians and pediatricians to attempt to identify the presence of fetal anomalies through radiographic and sonographic investigation before delivery, as this information may modify obstetrics management, or facilitate pediatric and surgical care. An unusual cause of polyhydramnios is fetal cervical teratoma.3,4 The present case is reported to demonstrate that polyhydramnios can be investigated prenatally. Additionally, the diagnostic and therapeutic problems of cervical teratoma are reviewed. CASE REPORT A 25-year-old, Latin American woman, gravida 4, para 2, aborta 1, at 36 weeks of gestation was referred for the evaluation of polyhydramnios. The patient had noticed an increase in abdominal girth which had occurred rapidly over the two weeks before admission and led to a shortness of breath. On sonographic examination a marked excess in amniotic fluid was identified and the fetal biparietal diameter was 95 mm; fetal anomalies could not be detected. To relieve the mother9s respiratory discomfort amniocentesis was done on two separate occasions and 3,800 ml of amniotic fluid was removed slowly. In order to evaluate fetal swallowing and gastrointestinal tract patency, 30 ml of 50% sodium-diatrizoate (Hypaque) were injected transabdominally into the amniotic sac. On a radiograph taken 12 hours later, the amniotic fluid was radiopaque, but no contrast material was identified in the fetal gastrointestinal tract.

Chromosomal abnormalities ascertained in the collaborative perinatal survey of 7- and 8-year-old children.

Abstract: Anxiety was measured and compared in three groups of 12 pregnant couples undergoing amniocentesis for prenatal diagnosis of chromosomal disorders. Significant elevations in anxiety were found in all groups prior to counseling on the day of the procedure and prior to receiving test results. Women who had previously given birth to a child with a chromosomal disorder displayed higher anxiety levels prior to amniocentesis than women whose indication for the procedure was age. Fathers in the previous trisomy group had higher anxiety levels prior to the receipt of test results as well as before the amniocentesis when compared to fathers in the maternal-age group. An experimental group of couples in which the women were over 35, received weekly calls from the genetic counselor. This intervention did not reduce median anxiety scores significantly for either men or women but did lower anxiety among the minority of extremely anxious mothers. Parental anxiety levels were interpreted based on interview data. Conditions which promote anxiety were contrasted to those which diminish it. Suggestions were made for amniocentesis counseling earlier in pregnancy and for identifying parents who would benefit by extra attention from counselors.

Sixteen years' experience of counselling, diagnosis, and prenatal detection in one genetic centre: progress, results, and problems.

Abstract: The work of one Genetic Centre over 16 years, covering about 14 000 kinships, is described. The numbers registered in a year increased from an average of 477 in the early 1960s to 1612 in 1976/1977. The increase is largely, but not entirely, attributable to the advent of prenatal diagnosis, and an account is given of our experience with this. In 1916 patients who had a successful amniocentesis, results indicative of fetal abnormality were found in 4.3% and a balanced translocation was found in an additional 0.9%. Results indicative of fetal abnormality were found in 3.5% of mothers referred because of a maternal age of 40 or more, 3.9% referred because of a high risk of neural tube defect, and 19.3% referred because of a high risk of an inborn error of metabolism. A number of cases with difficult diagnostic problems are described.

Congenital haemolytic anaemia resulting from glucose phosphate isomerase deficiency: genetics, clinical picture, and prenatal diagnosis.

Abstract: Glucose phosphate isomerase (GPI) deficiency with severe haemolysis and hydrops fetalis was found in the first child of unrelated, healthy Caucasian parents. The child died at 3 hours. Both parents were found to have 50% of normal red cell GPI activity and qualitative tests on their red cells and white cells showed that each was heterozygous for a different GPI variant allele associated with enzyme deficiency. Tests on the placenta showed that the propositus was a 'compound' heterozygote. Examination of amniotic cells obtained by amniocentesis on the mother at 28 weeks in her second pregnancy led to the prenatal diagnosis of GPI deficiency. This second child, a 'compound' heterozygote at the GPI locus indistinguishable from the first, was successfully treated by immediate exchange transfusion and subsequent blood transfusions.

Amniotic Fluid Cell Culture

Abstract: Cellular pleomorphism is a characteristic feature of amniotic fluid examined microscopically immediately following amniocentesis. Multiple cell types (with differing sites of origin) adhere to glass or culture vessels within 12-24 hr of plating (see Chapter 9 for more details). In amniotic fluid obtained in the late third trimester, many authors have noticed the presence of cells that stain orange with Nile blue sulfate (Brosens and Gordon, 1965; Anderson and Griffiths, 1968; Brosens et al., 1969). The four types of amniotic fluid cells observed after Nile blue sulfate cell staining are the parabasal, the blue intermediate, the anucleated blue squamous, and the anucleated orange staining (Husain and Sinclair, 1971). The appearance of these stained cells seems to correlate with the earliest keratinization of the stratum corneum, starting at about 17 weeks’ gestation (Serri and Montagna, 1961; Parmley and Miller, 1969). It is just possible that this evidence of keratinization prior to 20 weeks of pregnancy may ultimately lead to the prenatal detection of hereditary disorders of keratin, such as the ichthyoses (Goodman, 1970).

Fetal Cells in the Maternal Circulation

Abstract: Since the development of new, accurate methods for the detection of chromosome abnormalities and sensitive techniques for diagnosis of biochemical disorders, the whole field of prenatal diagnosis has come into a completely new light. Amniocentesis is nowadays carried out as a routine procedure in most major medical centers throughout the world, and the risks of complications associated with the procedure seem to be very low (see Chapter 2).

Measurement, Characterization, and Source of Somatostatin-like Immunoreactivity in Human Amniotic Fluid

Abstract: Somatostatin-like immunoreactivity (SLI) is widely distributed in tissues and biological fluids. To determine whether SLI is also present in amniotic fluid, samples obtained by amniocentesis from 30 normal and 27 abnormal pregnancies were studied by radioimmunoassay. Direct incubation of [125I-Tyr1]tetradecapeptide somatostatin (SRIF) with amniotic fluid resulted in 89% tracer degradation. Damage was reduced to <5% when samples were acidified and boiled before the assay. With this technique, SLI was detectable in all normal amniotic fluid samples; the mean level at 15-20 wk of gestation (320±55 pg/ml, n = 15) being 4.5 times higher than the mean at 32-43 wk (70±12 pg/ml, n = 15) (P < 0.001). In cases of preeclampsia (n = 6), gestational diabetes (n = 5), anencephaly (n = 1), and meningomyelocele (n = 1), SLI values were in the normal range, but in one juvenile diabetic and one patient with chronic renal failure, SLI was undetectable (<10 pg/ml). In a pair of monochorionic diamniotic twins, SLI levels were very different (33 and 197 pg/ml), which suggests that fetal factors are more important than materno-placental ones in determining amniotic fluid SLI. Serial dilutions of amniotic fluid showed parallelism with standard SRIF. When concentrates of pooled amniotic fluid were chromatographed on Sephadex G-25 columns, all SLI eluted in the void volume ahead of SRIF even after treatment with 8 M urea and dithiothreitol. This “big” SLI incubated in amniotic fluid showed 100% stability over 24 h at 37°C, whereas SRIF was rapidly inactivated (t½ ≅ 7 min). Extracts of placenta and fetal membranes contained no SLI, but small amounts (6-20% of total amniotic fluid SLI) were found in cells from fresh fluid. Radioimmunoassay of SLI in extracts of seven paired cord arterial and venous plasma samples showed no arteriovenous gradient consistent with fetal origin of cord blood SLI. It is concluded that (a) amniotic fluid contains SLI which is of fetal origin and (b) normal levels vary with gestational age. The SLI has a higher molecular weight (≥5,000) and is more stable in amniotic fluid than SRIF.

Utilization of Trophoblast for Early Prenatal Diagnosis

Abstract: Recent studies concerning the efficacy of amniocentesis for second trimester prenatal diagnosis have demonstrated the overall risk to be very low and the results to be very accurate.

Neonatal small-bowel obstruction associated with amniocentesis.

Abstract: volume, and total lung capacity.5 Any reduction in pulmonary mechanical efficiency must be avoided in respiratory failure, and controlled use of carbimazole may permit a fall in basal metabolic oxygen requirement but with thyroid function remaining within the normal range. Carbimazole would seem suitable for a double-blind controlled trial of treatment in chronic irreversible respiratory failure, and the drug may have a role in otherwise intractable cases while the results of such a study are awaited.