ISSN:0001-6349    

DOI:10.3109/00016348409156963

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Abstract.In 1979—1980 a multicenter study on serum alpha‐fetoprotein (S‐AFP) screening for detection of fetal neural‐tube and abdominal wall defects (NTD/AWD) was carried out in seven different regions in Sweden. A total of 22991 pregnant women, attending 84 public antenatal clinics, were offered an AFP test between their 15th and 18th completed gestational weeks. The average participation rate was 80.8%. The AFP assays were performed by five hospital laboratories, using the same commercially available assay method. In 19704 women screened, all with known pregnancy outcome, 17/22 fetuses affected by open NTD and 6/8 fetuses having AWD, gave S‐AFP levels exceeding 2 MOM. One placental haemangioma was recognized. Controlsampling was undertaken in 10.5% of the women. Amniocentesis was performed in 1.1% of all women screened with no false negative test results. However, three apparently normal fetuses were aborted at the parents request due to AFP levels in amniotic fluid exceeding 3 MoM.Thus, AFP screening in women at low risk enables detection of 3/4 of fetuses affected by NTD/AWD. A program with higher efficiency would be obtained by more accurate gestational dating by ultrasonography, by complementary diagnostic methods such as neurospecific acetylcholinesterase in amniotic fluid, by a reduction of the work‐load by shifting the action limit to 3 MOM and by continous appropriate training of the me

ISSN:0001-6349    

DOI:10.3109/00016348409156964

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Abstract.Alpha‐fetoprotein screening in large scale use implies certain practical consequences in obstetric practice as e.g. performance of a number of control assays in maternal serum (MS‐AFP), amniocentesis and ultrasonic examinations. Considerable regional differences were observed in the incidences of control assays (5.0‐10.5 per cent) and amniocenteses (0.2‐1.9) per cent when a “uniform” AFP‐screening program was run in seven scattered hospital regions in Sweden. The AFP assays were routinely performed by five hospital laboratories using the same commercially available assay method (Phadebas AFP PRIST). A total of 18030 singleton pregnant women were analyzed in their 15th to 17th gestational week.No significant differences were found between the regional distributions of MS‐AFP levels. By pooling the results, generally valid median (MS‐AFP) values, using this assay method, were determined for each relevant gestational week.The individual AFP‐test results were expressed in multiples of the normal median value (MOM) for singleton pregnancies of the same gestational age. There were no significant differences observed between the regional distributions of test results expressed in MOM‐values either.Thus, the variations in regional incidences of diagnostic follow‐up procedures found in the present study seemed to depend on the local obstetricians personal attitude and experience. The efficiency of the general screening program may well be significantly improved by employment of a more strictly standardized protocol for diagnost

ISSN:0001-6349    

DOI:10.3109/00016348409156965

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Abstract.The efficiency of a general AFP‐screening program is considerably affected by the action limit used for recommended diagnostic follow‐up procedures.We have analyzed if this efficiency could be enforced by the use of differential action limits for different purposes.A total of 18 037 pregnancies of known outcome were analyzed for their AFP‐levels in maternal serum (MS‐AFP) between the 15th and 17th gestational weeks. The individual AFP test results were expressed in multiples of the normal median value (MOM) for singleton pregnancies of the same gestational age. MS‐AFP levels ≤ 3 MOM were found in 22/28 pregnancies (78.6 per cent) affected by open neural tube‐ or abdominal wall defects, but only in 0.7 per cent of the 17 872 normal singleton pregnancies.Obstetric risk pregnancies, e.g. multiple pregnancies, impending abortions, and pregnancies eventually ending with perinatal deaths and children with low birth weight, were found to be overrepresented above the MS‐AFP level 1.8 MOM (the 94th percentile). The employment of differential action limits, i.e. at 3 MOM for further diagnostic attempts to eventually detect open neural tube‐ or abdominal wall defects, at 1.8 MOM for identification of certain obstetric risk pregnancies requiring close monitoring and below 0.25 MOM to reveal nonviable pregnancies to be terminated is likely to improve the efficiency of an AFP

ISSN:0001-6349    

DOI:10.3109/00016348409156966

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Abstract.The consequences of erroneous gestational dating on the efficiency of a maternal serum alpha‐fetoprotein (MS‐AFP) screening program has been studied in 1050 early pregnant women. The gestational age of each woman was independently estimated by means of menstrual dates as well as by ultrasonic measurements of the fetal crown‐rump length before the 15th week of gestation.Misinterpretation of the AFP‐test results because of incorrect gestational dating according to menstrual dates was observed in 5.4% of all women screened. 40% of the pregnant women with true “elevated” MS‐AFF values, according to ultrasonic dating, would have been misinterpreted as “normal” using menstrual dating. Incorrect menstrual dating was also found to account for 22% of all elevated MS‐AFP test results observed.Women who intend to take part in MS‐AFP screening programs should preferably have their gestational age determined be ultrasonography pr

ISSN:0001-6349    

DOI:10.3109/00016348409156967

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY