Alpha fetoprotein in amniotic fluid: An index of gestational age

1972 ◽  
Vol 114 (5) ◽  
pp. 595-598 ◽  
Author(s):  
M. Seppälä ◽  
E. Ruoslahti
Keyword(s):  
Amniotic Fluid ◽  
Gestational Age ◽  
Alpha Fetoprotein

Reactivity of amniotic fluid alpha-fetoprotein with concanavalin A in relation to gestational age: clinical implications.

1980 ◽  
Vol 26 (12) ◽  
pp. 1656-1659 ◽  
Author(s):  
K Toftager-Larsen ◽  
E Kjaersgaard ◽  
J C Jacobsen ◽  
B Nørgaard-Pedersen
Keyword(s):  
Amniotic Fluid ◽  
Clinical Significance ◽  
Concanavalin A ◽  
Gestational Age ◽  
Normal Values ◽  
Alpha Fetoprotein ◽  
Clinical Implications ◽  
Fetal Malformation ◽  
Average Decrease ◽  
Normal Outcome

Abstract We used concanavalin A crossed-line affinity immunoelectrophoresis to determine the percentage of concanavalin A nonreactive alpha-fetoprotein in amniotic fluid samples from pregnancies with normal and abnormal fetuses. In 167 samples from pregnancies with a normal outcome and normal values for total alpha-fetoprotein concentration in amniotic fluid the percentage decreased from a median value of 27.4% in the 13th week to 8.5% in the 21st week of gestation, and a statistically significant (p < 0.001) average decrease of 1.7% per week was found from the 14th to the 19th week. A similar average decrease (2.2%) was found in 22 pregnancies from which two or more samples were obtained. The clinical significance of this decrease is discussed. Of 108 samples from patients with above-normal values for total alpha-fetoprotein and a normal outcome, seven had a total alpha-fetoprotein above recommended cut-off values, and only one of these had a low percentage of concanavalin A nonreactive alpha-fetoprotein. In contrast, for all 27 samples from pregnancies with a severe fetal malformation this percentage was low, even in one case where the total alpha-fetoprotein concentration was below the recommended cut-off value.

Concanavalin A binding of alpha-fetoprotein in amniotic fluid as an aid in the diagnosis of neural tube defects.

1981 ◽  
Vol 27 (10) ◽  
pp. 1658-1660 ◽  
Author(s):  
P K Buamah ◽  
P Taylor ◽  
A M Ward
Keyword(s):  
Spina Bifida ◽  
Amniotic Fluid ◽  
Neural Tube ◽  
Neural Tube Defects ◽  
Concanavalin A ◽  
Gestational Age ◽  
Alpha Fetoprotein ◽  
Normal Outcome ◽  
Fetal Malformations ◽  
Open Spina Bifida

Abstract Concanavalin A nonreactive alpha-fetoprotein was determined in samples of amniotic fluid from 16 abnormal pregnancies complicated by anencephaly (7), open spina bifida (6), intra-uterine death (1), anencephaly with exomphalos (1), or open spina bifida with exomphalos (1), and in amniotic fluid from 50 normal pregnancies with gestational age between 13 and 24 weeks. In all 16 cases with fetal malformations, the proportion of nonreactive alpha-fetoprotein was significantly decreased (median 5.3%) as compared with amniotic fluid from pregnancies with a normal outcome (median 39.7%). The results confirm that this measurement is useful in the diagnosis of neural tube defects, especially when the concentration of alpha-fetoprotein in amniotic fluid is normal or only slightly above normal and gestational age is uncertain.

Fetal-maternal distribution of ovine alpha-fetoprotein.

1978 ◽  
Vol 235 (1) ◽  
pp. E27 ◽  
Author(s):  
P C Lai ◽  
G J Mears ◽  
G R van Petten ◽  
D M Hay ◽  
F L Lorscheider
Keyword(s):  
Amniotic Fluid ◽  
Gestational Age ◽  
Maternal Serum ◽  
Alpha Fetoprotein ◽  
Neonatal Development ◽  
Fetal Serum

The concentration of ovine alpha-fetoprotein (AFP) was determined in sheep fetal, maternal, and neonatal sera and amniotic fluid by radioimmunoassay. The fetal serum AFP concentration was highest during the first third of pregnancy and continued to decline with fetal and neonatal development. Total fetal synthesis of AFP was highest during the late middle and early latter third of pregnancy. Amniotic fluid AFP concentration was highest during the early middle third of pregnancy. Maternal serum AFP was not elevated above nonpregnant control levels during the first two-thirds of pregnancy, but instead showed a tendency to be elevated only during the last third of pregnancy. The fetal physiological distributions of ovine and human AFP in fetal serum and amniotic fluid appear to be similar, whereas in maternal serum the pattern of AFP levels differs in the two species as a function of gestational age.

Implementation of a screening program for diagnosing open neural tube defects: selection, evaluation, and utilization of alpha-fetoprotein methodology.

1986 ◽  
Vol 32 (10) ◽  
pp. 1812-1817 ◽  
Author(s):  
R L Christensen ◽  
M R Rea ◽  
G Kessler ◽  
J P Crane ◽  
R Valdes
Keyword(s):  
Amniotic Fluid ◽  
Neural Tube ◽  
Neural Tube Defect ◽  
Gestational Age ◽  
Screening Program ◽  
Maternal Serum ◽  
Alpha Fetoprotein ◽  
Standard Curve ◽  
Analytical Recovery ◽  
Commercial Kit

Abstract We evaluated and compared three different commercial kit immunoassays for alpha-fetoprotein (AFP) before we implemented our neural tube defect screening program. Each kit can be used with either serum or amniotic fluid. Analytical recovery ranges for AFP reference sera within each kit's standard curve limits (in kilo-int. units/L) were 97-108% (7.5-180) for the Kallestad kit, 77-101% (21.8-436) for Amersham, and 92-100% (0-177) for Hybritech. CVs, within each manufacturer's standard-curve limits, for combined intra-assay (amniotic fluid pools) and inter-assay (kit serum controls) averaged 3.6-7.3% (Kallestad), 2.4-9.3% (Amersham (y) kit results showed a correlation of r = 0.97, y = 1.05x + 5.5 kilo-int. units per liter of maternal serum (n = 66; range, 2.0-98.5). Gestational age did not influence these assay correlations. The Kallestad AFP assay demonstrated a maternal serum positivity rate of 2.9% at greater than or equal to 2.5 (n = 655) and 8.9% at less than 0.5 (n = 423) multiples of the median. All kits performed well analytically.

Sonographic Assessment of Amniotic Fluid Volume using Single Deepest Pocket (SDP) among Igbo Women with Uncomplicated Singleton Pregnancies.

2019 ◽  
Vol 2 (1) ◽  
pp. 1-18
Author(s):  
Chijioke Okeudo ◽  
B.U. Ezem
Keyword(s):  
Amniotic Fluid ◽  
Gestational Age ◽  
Cross Sectional Study ◽  
Fluid Volume ◽  
Singleton Pregnancy ◽  
Cross Sectional ◽  
South Eastern ◽  
Amniotic Fluid Volume ◽  
The Mean ◽  
Singleton Pregnancies

Background: The amniotic fluid is fundamental for proper fetal development and growth. Ultrasound visualization of the amniotic fluid permits both subjective and objective estimates of the amniotic fluid. Objective: The objective of this study was to determine the reference values of normal single deepest pocket (SDP) – upper and lower limits, mean SDP and variation of the SDP with gestational age among Igbo women of South-Eastern Nigeria extraction carrying uncomplicated singleton pregnancy. Methodology: This was a prospective cross sectional study involving 400 women carrying uncomplicated singleton pregnancies and who were sure of the date of the first day of their last menstrual period. The single deepest pocket / maximum vertical pool were determined once at presentation at the hospital.. The study was conducted from January 1st to December 31st 2015. The second author carried out all the scanning. The SDP was obtained. Results: The womens’ mean and median ages were the same at 28 years. The gestational age range of the pregnancies was 14-41 weeks. The mean SDP was 5.8cm, while the 5th and 95th percentiles were 3.3cm and 8.5cm respectively. There was no difference in the mean SDP in both term and preterm. There was irregular but continuous rise of mean SDP to a peak of 6.8cm at gestational age of 39 weeks. In conclusion, the participants had a mean SDP of 5.8cm. There was also a positive correlation between SDP and Gestational age. We therefore recommend a longitudinal study to assess perinatal outcome and abnormal amniotic fluid volume among Igbo women of South-Eastern Nigeria. Key words: Single Deepest Pocket, Uncomplicated Singleton Pregnancy, Igbo Women.

Laser Ablation of Posterior Urethral Valves by Fetal Cystoscopy

2015 ◽  
Vol 37 (4) ◽  
pp. 267-273 ◽  
Author(s):  
José María Martínez ◽  
Narcis Masoller ◽  
Roland Devlieger ◽  
Esther Passchyn ◽  
Olga Gómez ◽  
...  
Keyword(s):  
Renal Failure ◽  
Laser Ablation ◽  
Amniotic Fluid ◽  
Gestational Age ◽  
Significant Risk ◽  
Operation Time ◽  
Posterior Urethral Valves ◽  
Consecutive Series ◽  
Urethral Valves ◽  
Median Operation Time

Objective: To report the results of fetal cystoscopic laser ablation of posterior urethral valves (PUV) in a consecutive series in two referral centers. Methods: Twenty pregnant women with a presumptive isolated PUV were treated with fetal cystoscopy under local anesthesia. Identification and fulguration of the PUV by one or several firing-contacts with diode laser were attempted. Perinatal and long-term outcomes were prospectively recorded. Results: The median gestational age at procedure was 18.1 weeks (range 15.0-25.6), and median operation time was 24 min (range 15-40). Access to the urethra was achieved in 19/20 (95%) cases, and postoperative, normalization of bladder size and amniotic fluid was observed in 16/20 (80%). Overall, there were 9 (45%) terminations of pregnancy and 11 women (55%) delivered a liveborn baby at a mean gestational age of 37.3 (29.1-40.2) weeks. No infants developed pulmonary hypoplasia and all were alive at 15-110 months. Eight (40% of all fetuses, 72.7% of newborns) had normal renal function and 3 (27.3%) had renal failure awaiting renal transplantation. Conclusion: Fetoscopic laser ablation for PUV can achieve bladder decompression and amniotic fluid normalization with a single procedure in selected cases with anyhydramnios. There is still a significant risk of progression to renal failure pre or postnatally.

CAUTION IN INTERPRETATION OF AMNIOTIC FLUID INDICES OF FETAL PULMONARY MATURITY

PEDIATRICS ◽  
1989 ◽  
Vol 84 (2) ◽  
pp. A24-A24
Author(s):  
Student
Keyword(s):  
Amniotic Fluid ◽  
Gestational Age ◽  
Caesarian Section ◽  
Misleading Information

When gestational age has been firmly established by standard obstetric criteria, the risks of routine amniocentesis prior to repeat caesarian section in the uncomplicated term gestation [to obtain amniotic fluid indices of fetal pulmonary maturity] outweigh the usefulness of the potentially uninformative or misleading information gained.

Sign in / Sign up

Export Citation Format

Share Document