Influence of selected factors on serum AFP levels in pregnant women in terms of prenatal screening accuracy — literature review

Alpha-fetoprotein (AFP) is one of the biochemical components of the triple (T-3) and quadruple (T-4) test used so far in prenatal screening mainly for trisomy 21 (T21) and neural tube defects (NTDs). Based on many years of experience and data collected during these studies, a variety of factors have been identified that can affect a pregnant woman's serum AFP level, and thus the risk assessment of trisomy 21 (T21) and neural tube defects. These include both unaccounted for purely medical data (e.g., from baseline information about the patient, assisted reproduction methods used, comorbidities and emerging pregnancy pathologies) and errors made during statistical analysis. Since the triple or quadruple test is usually performed between 15 and 20 weeks of pregnancy, most scientific studies are based solely on results from this period of pregnancy — limited data are available for the first and third trimesters of pregnancy. In the era of new improved screening tests, AFP has the potential to become an independent marker for pregnancy well-being evaluation

Hepatic aminotransferases of normal and IUGR fetuses in cord blood at birth

Background: The accepted standard for assessing the wellbeing of the newborn is the Apgar score and blood gas analysis. However, the prediction of neonatal morbidity or mortality is limited. In small-for-gestation (SGA) fetuses at 18-38 weeks of gestation, pO(2) is <5th centile both in the umbilical artery and vein in 30%. In a previous study in singleton term neonates cardiac specific enzymes (B-type natriuretic peptide, BNP and cardiac troponin T, cTnT) are increased in growth-restricted fetuses compared with normals. Aims: To test the hypothesis, that fetuses with intra uterine growth restriction (IUGR) have elevated AST (GOT) and ALT (GPT) aminotransferases as a result of hypoxic liver cell injury, and to establish references ranges. Study design: Prospective cohort study, serum of umbilical artery (n = 156) and vein (n = 180), 599 normal singletons at 37(+0)-42(+0) weeks, neonates with IUGR (n = 41). analysis for pH, birthweight and maternal weight, spontaneous vs cesarean section, vein vs artery and for the sex. Outcome measures: Aspartate aminotransferase (AST. GOT) and Alanine aminotransferase (ALT, GPT) were measured in normals and IUGR neonates. Results: Neonates with IUGR (n = 41) had AST values that were not different from the reference group, but had significantly lower ALT (-1.49, 95% CI - 1.98 to - 1.00 vs 0.14, 95% CI - 0.42-0.13), (p<0.001), (Fig. 3). Conclusions: In neonates with IUGR, hypoxic hepatic injury markers in cord blood were not elevated. Rather, a substantially reduced ALT suggests a down-regulated hepatic activity. (C) 2011 Elsevier Ireland Ltd. All rights reserved

Alpha-fetoprotein (AFP) — new aspects of a well-known marker in perinatology

Alpha-fetoprotein (AFP) is a serum protein, which is characteristic of the fetal development period and a well-known oncological marker. The predominance of AFP among serum proteins is common in fetal life, whereas after birthing its functions are gradually taken over by albumins. An understanding of the mechanism of AFP transfer between fetus and mother has led to the development of screening tests for identifying neural tube defects and Down’s syndrome. Currently, the knowledge on patophysiology and the possible importance of AFP in perinatology and fetal medicine extends far beyond those 2 disease states. Throughout the 50 years of research on AFP, there has been dynamic progress of diagnostic techniques, from the qualitative ones that are used solely for scientific studies to the widely used radioimmunoassays and immunoenzymatic assays (enzyme-linked immunosorbent assay, chemiluminescence immunoassay, time-resolved fluorescence immunoassay). Some genetic mutations cause complete inhibition of AFP production by the fetus. This affects the results of screening tests during pregnancy, and also leads to constantly high levels of AFP in adults, which are not linked to oncogenesis.

Biochemical tissue-specific injury markers of the heart and brain in postpartum cord blood

OBJECTIVE: We sought to establish references ranges and to test the hypothesis that biochemical tissue-specific markers for the heart in umbilical cord blood of newborns with cardiac defects and intrauterine growth restriction (IUGR) are abnormal. STUDY DESIGN: A prospective study was conducted. Serum samples of the umbilical vein (n = 280) and artery (n = 156) from 599 healthy newborns at 37(+0)-42(+0) weeks of gestation were collected. Total creatine kinase (CK), CK-MB heart type (CK-MB), cardiac troponin T (cTnT), myoglobin, N-terminal pro-B-type natriuretic peptide (NT-proBNP), and S100 were measured. Reference ranges for each marker were constructed. Concentrations of tissue-specific markers from umbilical cord blood of neonates with cardiac defects (n = 10) and IUGR (n = 41) were plotted against the established reference ranges. RESULTS: Reference ranges for each studied marker were established for both umbilical artery and vein. In fetuses with cardiac defects, both NT-proBNP (4/6 [66%] in the artery, 7/10 [70%] in the vein) and cTnT (2/10 [20%] in the vein) were increased. In fetuses with IUGR in the vein, NT-proBNP (10/41 [24%]) and cTnT (5/41 [12%]) were increased, whereas S100 (9/41 [21%]) was decreased. CONCLUSION: In a subset of neonates with cardiac defects or growth restriction, irrespective of the pH at birth, tissue-specific injury markers for the heart in umbilical cord blood are abnormal

Associations between the Level of Trace Elements and Minerals and Folate in Maternal Serum and Amniotic Fluid and Congenital Abnormalities

Congenital birth defects may result in a critical condition affecting the baby, including severe fetal/neonatal handicap and mortality. Several studies have shown that genetic, nutritional, and environmental factors may have an impact on fetal development and neonatal health. The relevance of essential and toxic elements on fetal development has not yet been fully investigated, and the results of recent research indicate that these elements may be crucial in the assessment of the risk of malformations in neonates. We determined the association between essential and toxic elements and the level of folate in maternal serum (MS) and amniotic fluid (AF), along with neonatal abnormalities. A total of 258 pregnant Polish women in the age group of 17–42 years participated in this study. AF and MS were collected during vaginal delivery or during cesarean section. An inductively coupled plasma mass spectrometry technique was used to determine the levels of various elements in AF and MS. The results of this exploratory study indicate that the levels of essential and toxic elements are associated with fetal and newborn anatomical abnormalities and growth disorders.Land and Food Systems, Faculty ofOther UBCNon UBCReviewedFacult