SEARCH · PubMed Health
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
One hundred and seventy-six amniocenteses were performed in the Johannesburg Amniocentesis Clinic in 1976. These were for genetic studies, assessment of fetal lung maturity and assessment of the severity of rhesus disease. The indications for amniocentesis and the results are discussed. The overall complication rate was low. This was due to certain precautions and approaches taken, which are detailed.
Explore the source record for details and available documents.
Amniocentesis for estimation of the lecithin: sphingomyelin (L/S) ratio was performed on 483 patients on 552 occasions. The introduction of this test has been associated with a highly significant (p less than 0-001) decrease of 59 per cent in the incidence of respiratory distress syndrome. The finding of a low L/S ratio (less than 2-0) enabled delivery to be deferred until lung maturity had been reached in 43 (10-3 per cent) of the 419 patients who had successful amniocentesis. Fetal death occurred after amniocentesis in two patients (0-41 per cent). One fetus died after haemorrhage occurred behind an anterior placenta and the other died of exsanguination. Failed amniocentesis occurred in 64 patients (13-2 per cent), and was more common when the placenta was anterior or was not located before the procedure and when fetal growth was retarded. Fetal distress in labour occurred more commonly after failed amniocentesis. Spontaneous labour followed amniocentesis in 47 patients (9-7 per cent) and was significantly more prone to occur after 38 weeks gestation. Rhesus isoimmunization did not occur in any of the rhesus-negative patients who delivered rhesus-positive babies and who were screened six or more months after amniocentesis, although anti-D immunoglobulin was not given routinely after amniocentesis. Suggestions are made as to how the success rate of this valuable procedure can be improved and how some of the serious fetal and maternal sequelae can be avoided.
Three hundred eighty amniocenteses in 200 parturients were reviewed for success or failure in obtaining amniotic fluid, number of attempts for each amniocentesis, premature rupture of the fetal membranes, presence of blood, and the perinatal outcome. The highest success rate was in cases in which amniocentesis was performed between the symphysis and the presenting part of the fetus. The total incidence of spontaneous rupture of fetal membranes within 5 days after the last amniocentesis was 13.5%. When the amniocentesis was performed behind the fetal neck, the membranes ruptured significantly more frequently (P less than 0.05) than after amniocentesis at other sites. It is concluded that the area behind the fetal neck should be avoided if possible at amniocentesis. There were no severe be avoided if possible at amniocentesis. There were no severe fetal or neonatal complications from amniocentesis in these patients.
A review of the literature indicates a small but significant incidence of fetal-maternal hemorrhage following amniocentesis. In these studies, consideration has not been given to the frequency with which erythrocytes containing hemoglobin F are to be found in the maternal circulation in the absence of amniocentesis. In this investigation, Kleihauer-Betke analysis was carried out before and after amniocentesis. This study confirms previous reports that spontaneous fetal maternal hemorrhage is not uncommon during normal intrauterine gestation and that amniocentesis is probably only an occasional cause of fetal-maternal hemorrhage. This impression is based on the findings that most Kleihauer-positive maternal blood samples after amniocentesis were also positive before amniocentesis. In spite of these findings, and since Rh-immune serum globulin is apparently harmless to the fetus and mother, its use is still advocated in nonsensitized Rh-negative mothers after amniocentesis.
Amniocentesis is a technic to which it is now made more and more reference, even when feto-maternal incompatibility is not involved, for many various indications and at variable chronology along pregnancy. Our study concerns the risk developing Rh immunization among Rh negative women, undergoing amniocentesis early in pregnancy. 233 women had 243 amniocentesis between 16 and 21 weeks of pregnancy. Fetal cells in the maternal circulation were searched for using the Kleihauer's acid elution technic. In 154 cases, the Kleihauer's method was also used just before the amniocentesis, in order to run out a spontaneous foeto-maternal haemorrhage and to correlate the 25 (16,2%) transplacental haemorrhage reported to amniocentesis. When ever the result was positive, we observed a feto-maternal ratio varying from 1/20 000 to 100/20 000 but it is very difficult at this early period of fetal life to assure a precise volume of blood from this ratio. Placental localization preceeding amniocentesis does not seem minimizing the risk of bleeding. Althrough the occurence of a fetal bleeding seems to be more frequent in cases where blood can be demonstrated in the amniotic fluid (8/25 = 32%) than in cases it is not, the estimated volume of the foeto-maternal haemorrhage is not related to the presence or absence of blood in the amniotic cavity. In 3 cases the intra-amniotic blood was tested by the Kleihauer's method. In two instances there was a mixture of adult and fetal cells. In the 3rd case only fetal cells were present. In this last case, as in 17/25 bloody amniotic fluid (68%) no feto-maternal haemorrhage could be demonstrated. The risk of Rh immunization commands prophylaxis. In such Rh negative women, we inject intravenously a 85 mug dose of anti-D immunoglobulin, soon after performing amniocentesis, what ever the result of Kleihauer test is positive or negative.
On the basis of the large, well-controlled, prospective study from the NICHD, it can be stated that midtrimester ammniocentesis is safe if properly performed. The details of performance, with emphasis on possible pitfalls, are presented in an effort to encourage more practicing obstetricians to begin performing the procedure in cooperation with their area genetics laboratories (11). Emphasis is also placed on performing this procedure in a manner most likely to produce success. This success is measured not only in obtaining the fluid, but more importantly in gaining useful information from the analysis of the fluid. Although the aspects of diagnosing and preventing genetic disease have been emphasized, perhaps the greatest value of midtrimester amniocentesis is the reassurance afforded the more than 95% of couples when the fluid analysis is normal (19). The consumer demand for amniocentesis is rapidly increasing. Although the medicolegal implications of the techniques are not fully understood at present, it is clear that failure on the part of a clinician to offer indicated diagnostic amniocentesis may make the clinician vulnerable to litigation if the pregnancy outcome is abnormal. The demand for amniocentesis and laboratory analysis of the fluid will soon overtax existing facilities. Until such time as new and expanded facilities are available, discretion must be used in offering the procedures. Governmental action may soon be forthcoming to provide facilities designed to make midtrimester diagnostic amniocentesis available to all for whom it is indicated.
A total of 2702 transabdominal amniocenteses performed at the Los Angeles County--University of Southern California Medical Center were reviewed, with particular emphasis on 392 samples performed beyong 41 weeks' gestation. A significant rise in the percent of amniocenteses with meconium staining was found to occur at an beyond 39 weeks. Meconium-stained fluid at amniocentesis was found to be associated with an increased incidence of babies weighing greater than 4000 g, maternal diabetes mellitus, and cesarean deliveries, in comparison to samples with clear amniotic fluid. Infants with meconium-stained fluid had an increased incidence of low 1-minute Apgar scores, but all 5-minute Apgar scores were 7 or greater. Ten perinatal deaths occurred after an amniocentesis with clear fluid in prolonged pregnancy, with four of these occurring within 7 days of amniocentesis. Lecithin/sphingomyelin (L/S) ratios less than 2.0 were found in 6% of amniocenteses performed beyond 41 weeks. However, none of the newborns with low L/S ratios develop subsequent neonatal respiratory distress syndrome. Amniotic fluid creatine values or blood-contaminated fluid were not found to be correlated with fetal outcome. No fetal mortality was attributable to amniocentesis. In view of the significant amount of false-positive and false-negative results, and the rare inherent danger associated with amniocentesis, its use solely to demonstrate the presence or absence of meconium staining appears to be of questionable value in the management of prolonged pregnancy.
This prospective study of the safety and accuracy of midtrimester amniocentesis involved 1,040 subjects and 992 controls. Immediate complications of amniocentesis (vaginal bleeding or amniotic fluid leakage) occurred in approximately 2% of the women. There was no statistically significant difference between the two groups in rate of fetal loss (3.5% for the subjects, 3.2% for the controls) or incidence of complications of pregnancy of delivery. Newborn examination indicated no significant differences between the two groups in incidence of congenital anomalies and no evidence of physical injury resulting from amniocentesis. The two groups did not differ significantly in physical, neurological, or developmental status at one year of age. Diagnostic accuracy was 99.4%. Midtrimester amniocentesis is a highly accurate and safe procedure that does not significantly increase the risk of fetal loss or injury.
A study was designed to determine whether there is an increased risk of complications when amniocentesis for fetal sex determination is performed on hemophilia carriers. Questionnaires were sent to 112 medical centers providing this service in the United States, and to 19 outside the United States. Responses were received from 76% of the centers in the United States. Data on 11,819 taps were obtained. Only 75 taps (0.64%) were performed for the indication of hemophilia. The frequency of fetal deaths in the general sample (1.84%) was not significantly different from that in the subsample of hemophilia carriers (1.33%). The results of this survey correspond very closely to data from a National Registry on amniocentesis for various indicaions in such variables as the number of taps needed for diagnosis, color of the fluid obtained, and number of dry taps. Carrier women who had bleeding problems during the monitored pregnancy are described. The problems might have been related to the amniocentesis in three women. It is calculated that only 2-4% of hemophilia carrier women who might have amniocentesis are utilizing the service.
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.
In 139 patients for prenatal diagnosis 186 amniocenteses were required. The repetiion of amniocentesis followed in 12.3% due to failure of cell growth, in 1.1% due to failure to obtain fluid, and in 10.2% to performe the fetography. In 3 pregnant women 2 repetitions were indicated. Although the amniocentesis were performed without ultrasound, in 92% the first insertion of needle were already succeeded in obtaining fluid. In repeated amniocenteses no significant differences were found. Brownish fluid were observed in 4.7% of the first amniocentesis. With 24.4% it was significantly more frequent in the repeated amniocenteses. Bloody taps appeared in each fifth puncture, but only in 2.8% blood fluid were also withdrawed for cell culture. 82.9% of the first amniocentesis followed between 16 and 19 week's gestational age and the result was present after 20.3 days on an average. The abortion rate was 4.3%. Among the newborns one hydrocephalus with questionable needle mark, one microcephalus and one further child with questionable needle mark were found. In one duodenal atresia and in one achondroplasia an inconclusive result was obtained. Two erroneous diagnoses of sex occurred and no diagnosis was obtained in two women.
Needle puncture of the fetus has rarely been reported with midtrimester amniocentesis. This paper contains the report of five cases of needle scars in infants born after second-trimester amniocentesis for prenatal diagnosis of fetal genetic disorders. Since this complication may be more frequent than has been previously believed, there is the possibility that damage to the fetus may occur. It is suggested that the products of all abortions and all live-born and stillborn infants delivered following amniocentesis should be examined for evidence of injury.
The indications, technique, and potential complications of the now commonly used obstetric procedure, amniocentesis, have been reviewed. Although amniocentesis is considered by many a routine and a very safe procedure, there are potential complications, especially for the fetus, but for the mother as well. The frequency of these complications can be reduced by meticulous attention to technique and especially by preliminary placental localization. The latter is probably best accomplished by the ultrasound B scan. Because there are potential complications, the indications and timing of amniocentesis must always be carefully weighed before it is carried out.
The value of preliminary ultrasonography as a guide for amniocentesis in the early second trimester of pregnancy was prospectively evaluated. One hundred and fifty patients were alternately assigned to a control group or to an ultrasound group who underwent examination with a real-time scanner immediately prior to amniocentesis. All amniotic fluid samples were assessed as to the presence of blood by: (1) visual observation during the amniocentesis; (2) appearance of the centrifugate; and (3) microscopic analysis. Ultrasonography did not reduce the failure rate, the incidence of multiple needle insertions, or the proportion of amniotic fluid samples containing blood.
With the increased use of routine ultrasonography at the time of genetic amniocentesis, twins are increasingly likely to be discovered at the time when the procedure is to be carried out. In the presence of twins the likelihood of finding an abnormality may be significantly increased, but at the same time problems such as discordance between the twins for the abnormality, or the inability to test both twins may occur. This altered situation may affect the parents' decision as to whether or not to undertake amniocentesis, and the need for additional counseling prior to proceeding with the amniocentesis is stressed.
Since 1972, we have performed 951 early amniocentesis in 902 pregnant women. There were 19 twin pregnancies, all diamniotic, representing 2.1% of the sample. Diagnosis was always suspected before the amniocentesis. It was confirmed by echography in the 14 cases in which this technique was used. Out of the first 5 cases without echography, we punctured only one sac. In the 14 last cases, the process was successful in 13 cases thanks:--the perfection of echography showing the exact location of the fetuses and the position of the septum--the injection of congo red (12 cases) or methylene blue (2 cases) into the first sac. The indications were as follows: chromosomal aberrations (14 cases) metabolic diseases (1 case), sex-linked disorders (1 cases) neural tube defects (3 cases). No complications due to amniocentesis were observed but three abortions and one fetal death occurred. The reason why is discussed. We have made only one therapeutic abortion.
212 amniocentesis were performed at the Gynecological Clinic of the University Graz in cooperation with the Institute for Human Genetics of the same University from 1.7.1974 to 1.4.1978 for prenatal detection of genetic disorders or inherited disorders of metabolism. In 9 cases (4,2%) pathological results or special chromosomal aberrations were found. Five pregnancies (2,3%) had to be interrupted with prostaglandins. One case of Down-Syndrome ended by spontaneous abortion. Three women had a miscarriage following amniocentesis up to 6 weeks afterwards. In two cases (0,9%) a primary connection of puncture and loss of pregnancy could be documented. 4 cases (1,8%) suffered of amniotic fluid leakage after amniocentesis. Three patients delivered healthy term babies. This study demonstrates the high accuracy of the described diagnostic procedures.