Showing papers on "Amniocentesis published in 1984"

Maternal age specific rates for chromosome aberrations and factors influencing them: Report of a collaborative european study on 52 965 amniocenteses

Abstract: Maternal age specific rates for all major chromosome aberrations have been determined in 52 965 pregnancies in mothers 35 years of age and over at the time of amniocentesis. Rates increase exponentially with advancing maternal age for trisomies 21, 18 and 13, and for the XXX and XXY syndromes, but in the autosomal trisomies this rise appears to be followed by a levelling off at the upper end of the age range. A significant inverse relationship with maternal age is found for 45,X cases. It is postulated that these various patterns are the result of the interaction of three principal factors: a maternal age effect acting particularly on first meiotic nondisjunction: a higher spontaneous abortion rate with advancing maternal age for aneuploid as compared to euploid conceptions; and an increased probability of spontaneous abortion before the time of amniocentesis for conceptions with more extensive chromosome imbalance. A stepwise logistic regression analysis of 13 299 pregnancies in which both parental ages are known shows that the father's age does not influence these maternal age specific rates, with the possible exception of the 47,XXY syndrome.

An Endogenous Ouabain-Like Factor Associated with Hypertensive Pregnant Women*

Abstract: Levels of a ouabain-like factor (OLF) were measured in amniotic fluid from 49 undigitalized third trimester pregnant women by means of its cross-reactivity in a digoxin RIA and its inhibition of ouabain-sensitive [Na,K]ATPase. The results from these 2 assays were significantly correlated (P less than 0.05). Of the women included in this study, 25 had blood pressures considered normal for their gestational age, while 24 had developed during their current pregnancy blood pressures judged to be elevated. When levels of OLF in the amniotic fluids from the normotensive and hypertensive pregnant women were compared, significantly higher levels were present in the hypertensive group for both assays (P less than 0.002). Further, there was a significant correlation between the diastolic blood pressures of these women at the time of amniocentesis and the amniotic fluid OLF levels determined by either assay (P less than 0.002). These results are consistent with OLF having a role in hypertensive complications of pregnancy.

Outcome of cases of de novo structural rearrangements diagnosed at amniocentesis

Abstract: The frequency of de novo rearrangements at amniocentesis was determined in 76952 prenatal diagnoses from centres in the United States. Rates for balanced rearrangements are slightly greater than rates previously reported in the newborn, possibly because banding studies were not used in the latter. Rates for unbalanced rearrangements are considerably higher in the amniocentesis data not only because banding was used but also because a substantial loss of abnormal conceptions is to be expected between amniocentesis and birth. The higher frequency of cases with supernumerary markers at amniocentesis is unexplained. A review of 66 apparently balanced de novo rearrangements found at amniocentesis revealed evidence of abnormality in five; in four of these the abnormality was noted in the abortus. The number of cases observed is still too small to rule out a risk of abnormality no greater than the usual rate of abnormalities at birth. Abnormalities were detected in 6 of 10 cases with unbalanced de novo rearrangements. In 33 cases of non-familial supernumerary chromosomes 6 (18.2 per cent) showed abnormality. Non-satellited markers appeared to have a higher rate of abnormality than satellited markers but the difference is not statistically significant. Further studies and improved follow-up of de NOVO cases diagnosed at amniocentesis are required.

Insulin-like growth factors in amniotic fluid

Abstract: The concentrations of insulin-like growth factors I and II (IGF-I and IGF-II) in amniotic fluid were determined by specific immunoassays in 58 women IGF-I concentrations were constant throughout gestation at approximatey 20 ng/ml; the mean IGF-II concentration was 114 ± 13 (±SE) ng/ml at the earliest period of gestation studied and remained unchanged at 26 to 33 weeks despite a greater than 50% decrease in amniotic fluid total protein A precipitous decrease in IGF-II concentration occurred at term which was not explainable by alterations in total amniotic fluid protein concentration The concentrations of IGF-I and IGF-II in amniotic fluid did not correlate with concentrations of these factors in maternal serum (r = 008 and 009, respectively) [125I]IGF-I and [125I]IGF-II, after incubation with amniotic fluid, bound to a 40–45 K protein (or proteins) A carrier protein of greater mol wt, as in serum, was not detected These findings indicate that there is dynamic control of IGF in amniotic fl

Intrauterine Fetal Demise in Multiple Gestation

Abstract: Fifteen cases were reviewed over a five-year period at a perinatal centre with intrauterine demise of one member of a multiple gestation. Nine cases were monozygotic twin pairs, two were dizygotic, and two were triples . Gestational age ranged from 27 to 39 weeks. The management protocol consisted of delivery in all cases after confirmation of the diagnosis. In 4 cases delivery was immediate because of spontaneous labor. In the other cases elective delivery was performed if the gestational age was 37 weeks or greater or there was evidence of preeclampsia or if amniocentesis revealed a mature lecithinsphingomyelin (L/S) ratio. Steroids were given if the L/S was immature or the attempt at amniocentesis was unsuccessful and delivery was performed 48 hours after initiation of steroid therapy. Cesarean section was the mode of delivery in 14 of the 15 cases. All of the cotwins and cotriplets survived. One survivor of a monozygous twin pair has multicystic encephalomalacia possibly implicating perinatal arterial occlusion or in utero disseminated intravascular coagulation (DIC). The intrauterine deaths are categorized into possibly avoidable deaths (2/15), unavoidable due to congenital anomalies (3/15), and unknown or unavoidable deaths (8/15).

Risk for chromosome abnormality at amniocentesis following a child with a non‐inherited chromosome aberration a european collaborative study on prenatal diagnoses 1981

Abstract: Based on 2890 prenatal diagnoses from 12 European countries the risk for a chromosomally abnormal fetus at amniocentesis after the birth of a child with a chromosome abnormality has been estimated to be 1.3 per cent when the mother's age is 34 years or less at amniocentesis and 1.8 per cent if the mother is older. This risk does not depend on paternal age, and it is independent of the type of the chromosome abnormality of the index child. Some geographical heterogeneities were detected. Therefore, the overall risk has to be considered as a rough estimate. The chromosome constitution of the abnormal fetus differed from that of the index patient in 21 of 41 cases. Several explanations for the higher risk have been discussed. If the index child had trisomy 18, 13 or a sex chromosome abnormality, the fetus tended to be a female. If the index child was a trisomy 21, the fetal sex ratio was normal.

The fetal face: ultrasound examination.

Abstract: Abnormalities of the fetal face were identified by ultrasound in five cases. Abnormalities such as cleft lip and palate, cyclopia, and forms of holoprosencephaly were diagnosed prenatally. Two of the fetuses had trisomy 13. When facial abnormalities are identified a careful search of the fetus for associated anomalies is indicated; amniocentesis for genetic study may be desirable. In addition, evaluation of the fetal face may be useful when other fetal abnormalities are present.

The frequency of 47,+21,47,+18, and 47,+13 at the uppermost extremes of maternal ages: results on 56,094 fetuses studied prenatally and comparisons with data on livebirths.

Abstract: We examined the proportions (or so called “rates”) of fetuses with 47,+21, 47,+18, or 47,+13 diagnosed prenatally in women at the upper extremes of age. Our analysis was prompted by results from a large scale European study of amniocentesis which indicated that after increasing exponentially from age 35 years, the proportions of the autosomal trisomies reached a peak at a specific age and then leveled off or declined at the upper end of the age range. We analyzed North American data on 56,075 fetuses studied because of no known cytogenetic risk factor (aside from maternal age). This is the largest series to data. For 47,+21, the data from amniocentesis studies provide no evidence for any drop in the rate of change of proportion with maternal age up to 49 years. There is, if anything, a trend in our data to a steepening in the exponential rate of change at the upper extreme of age (above 46 years). Data from livebirths on the Down syndrome phenotype are at least consistent with an exponential rate of increase in proportion affected up to age 49 years. For 47,+18 our data from prenatal diagnoses are more consistent with an exponential increase up to age 43 years and a level proportion (or “rate”) after that. For 47,+13 no cases were observed above age 42 years, consistent with the drop in proportion affected above this age observed in the European series. We emphasize the possible effect of sampling fluctuation and reporting error upon these apparent trends.

Amniocentesis in the identification of inapparent infection in preterm patients with premature rupture of the membranes.

Abstract: Twenty-nine preterm patients with premature rupture of the membranes who were not in labor and who did not have clinical chorioamnionitis underwent successful amniocenteses. Nine fluids were positive for bacteria. Subsequent clinical chorioamnionitis and shorter latency periods were more common in these 9 patients than in the 20 with sterile amniotic fluid. Positive fluids were more likely to be obtained from patients tapped within 48 hours of membrane rupture. In most patients with heavy bacterial growth, clinically apparent infection and/or labor soon supervened.

Rapid Prenatal Diagnosis of Glycogen-Storage Disease Type II by Electron Microscopy of Uncultured Amniotic-Fluid Cells

Abstract: Glycogen-storage disease Type IIa is a fatal, genetically determined disease of infancy or early childhood that is characterized by deficient activity of acid alpha-glucosidase and by the presence of intracellular vacuoles full of glycogen, which are found in most tissues, including skin and liver. On electron microscopy these specific vacuoles are tightly packed accumulations of glycogen particles surrounded by a single membrane. We did electron-microscopical examinations on uncultured amniotic-fluid cells from 26 women whose fetuses were at risk for glycogen-storage disease Type IIa and from 8 normal control pregnant women. We found specific vacuoles in cells from 6 of the 26 high-risk patients. At delivery, glycogen-storage disease Type IIa was present in the infants of these 6 women and absent in those of the other 20 according to results of clinical, biochemical, and electron-microscopical studies of gestational products. After amniocentesis at 15 to 18 weeks of gestation, the prenatal diagnosis made by electron microscopy of uncultured amniotic-fluid cells was available in three to six days, whereas it took from three to six weeks to make the diagnosis by enzymatic analysis of the cultured amniotic-fluid cells. We conclude that the electron-microscopical prenatal diagnosis of glycogen-storage disease Type IIa is rapid, safe, and reliable. It should facilitate earlier diagnosis and thereby help to preserve parental options.

Conservative versus aggressive management of preterm rupture of membranes. A randomized trial of amniocentesis

Abstract: Amniocentesis to guide the management of preterm pregnancies complicated by premature rupture of the membranes (PROM) has been adopted at several centers. The purpose of this study was to evaluate this practice prospectively among comparable groups of patients, which has not previously been reported. Forty-seven patients with PROM at 26 to 34 weeks of gestation and an accessible pocket of amniotic fluid by ultrasound examination were randomly assigned to an "amniocentesis group" (N = 25) or to a "no amniocentesis group" (N = 22). Amniocentesis results were utilized when making management decisions in the amniocentesis group, whereas a clinical basis alone was used in the no amniocentesis group. Demographic variables were similar between the two study populations at the time of randomization. There were no antepartum fetal deaths and one neonatal death in each group. Fetal distress, as judged by the fetal monitor tracing, was more frequent in the no amniocentesis group (P less than .05). The number of days the infant remained in the hospital was significantly less in the amniocentesis group (median = 8.5 days, range 2 to 88 days) than in the no amniocentesis group (median = 22 days, range 2 to 110 days, P less than .01). This difference in neonatal hospital days appeared to be mainly due to a slower resolution of the multiple problems of prematurity. No significant differences in these complications were demonstrated individually. No differences in antepartum hospital days, postpartum hospital days, postpartum endometritis, or sepsis were apparent between the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Parental response to mid-trimester therapeutic abortion following amniocentesis.

Abstract: This article reports the results of a retrospective study designed to examine the responses of couples to genetic amniocentesis and subsequent therapeutic abortions due to birth defects. Fourteen women and 12 men were interviewed by experienced interviewers using a structured format designed by the authors, and each interview was audiotaped for later rating. The 5 raters (all women) were instructed to independently rate each interview using forms designed by the authors to elicit information about many aspects of the participant's individual responses as well as perceptions of spouse's responses to the process of pregnancy, amniocentesis, therapeutic abortion, and sequelae. Ratings of all 5 raters were conjoined and an homogeneous narrative was constructed for each interview. Results indicate, in general, that the respondent couples coped well with this experience. In fact 70 per cent of the respondent couples described their marital relationships as becoming closer as a result of their experience. Only a few participants reported long-term deleterious effects. Most couples coped by relying on relatives, friends, and occasionally, professional counsellors. In addition, most participants in this study suggested ways to improve the medical and psychological aspects of this experience.

Predictive value of amniotic acetylcholinesterase analysis in the diagnosis of fetal abnormality in 3700 pregnancies.

Abstract: The value of acetylcholinesterase (AChE) analysis as an adjunctive test to amniotic alpha fetoprotein (amAFP) for the diagnosis of fetal abnormality has been investigated in a series of 3785 amniotic fluid samples. Quantitative analysis of AChE performed retrospectively on a selected group of 541 amniotic fluid samples failed to discriminate between normal and open neural tube defect pregnancies. Qualitative analysis of AChE by polyacrylamide gel (PAG) electrophoresis in the same series of 541 fluids correctly identified 251 of the 255 pregnancies with open neural tube defect and 29 of the 31 pregnancies with false positive amAFP results. The failure of the test to diagnose 4 cases of open neural tube defect was probably attributable to the age and condition of the stored AF samples. Routine diagnostic testing of AChE isoenzymes in a further 3244 AF samples successfully identified all 170 cases of open neural tube defect and 20 cases with other fetal defects. Thirteen fluids gave false positive AChE results (0.4 per cent) compared to 59 of the series in which there were false positive amAFP results (1.8 per cent). Six of the 13 false positive AChE cases had AChE bands of low intensity which would not be regarded as diagnostic of fetal abnormality, and in five the AChE band may have been the result of significant blood contamination. False positive AChE results contributed to the decision to abort three apparently normal fetuses, but a normal AChE result undoubtedly helped to save a number of pregnancies with false positive amAFP results. Our experience suggests that repeating the amniocentesis may help in resolving the rare diagnostic difficulty of a positive AChE result with or without an elevated amAFP in the absence of ultrasound evidence of fetal abnormality, particularly where there is blood contamination of the amniotic fluid sample.

Prenatal diagnosis of citrullinemia: elevated levels of citrulline in the amniotic fluid in the three affected pregnancies.

Abstract: In three pregnancies at risk for citrullinemia affected fetuses were predicted both by strongly increased levels of citrulline in the amniotic fluid and by the reduced incorporation of 14C-citrulline into TCA-precipitable material in cultured amniotic fluid cells. The prenatal diagnoses of affected fetuses were confirmed after termination of the pregnancies by direct and indirect assays of argininosuccinate synthetase in the fetal livers and fibroblasts respectively. Measurement of the citrulline concentration in amniotic fluid appears to be a valuable adjunct in the prenatal diagnosis of citrullinemia.