Gestational age, and

Prenatal (general population) Developmental Reduced birth weight and/or reduced gestational age, and/or increased incidence of stillbirth and neonatal death 12-17 Bornschein et al. 1989 McMichael et al. 1986 Moore et al. 1982 Ward et al. 1987 Wibberley et al. 1977... 

H.E. Meyer Zu Schwabedissen, M. Grube, B. Heydrich, K. Linnemann, C. Fusch, H.K. Kroemer, and G. Jedlitschky. Expression, localization, and function of MRP5 (ABCC5), a transporter for cyclic nucleotides, in human placenta and cultured human trophoblasts Effects of gestational age and cellular differentiation. Am J Pathol. 166 39 18 (2005). 

Andrews KW, Savitz DA, Hertz-Picciotta I Prenatal lead exposure in relation to gestational age and birth weight a review of epidemiologic studies. AmJ Ind Med 26 13-32, 1994... 

The analysis was adjusted for gestational age and took account of two covariates the standard gestational age was 39 weeks and ... 

Ballard PL, Ballard RA, Ning Y, Cnann A, Boardman C, Pinto-Martin J, Polk D, Phibbs RH, Davis DJ, Mannino FL, Hart M. Plasma thyroid hormones in premature infants effect of gestational age and antenatal thyrotropin-releasing hormone treatment. TRH Collaborative Trial Participants. Pediatr Res 1998 44(5) 642-9. 

G.W. Mihaly and D.J. Morgan, Placental drug transfer Effects of gestational age and species, Pharmac. Ther. 23 (1984) 253-266. 

I-cell disease is suspected clinically by the phenotype and is confirmed biochemically (cf. Biochemical Perspectives section). The infant with I-cell disease is usually small for gestational age and is clinically differentiated from having Hurler s syndrome by earlier onset of signs and symptoms, the absence of excessive mu-copolysacchariduria, short stature, and the rapidly progressive course, leading to death usually by age 4 years. 

In order to determine the statistical distribution of amniotic fluid samples taken at different gestation weeks, two relations are studied rupture of foam films (VP = 0) and development of RDS, and formation of a bilayer foam film (W = 1) and normal respiratory status of neonates. These correlations allowed to develop a new diagnostic method for estimation of lung maturity [20]. The function of the threshold dilution of various amniotic fluid samples (corresponding to C,) on the gestation age and the clinical results (i.e. yes/no RDS in neonates) is given in Fig. 11.5. The respiratory status of the neonates is studied with the screening system of Masson et al. [26], modified by Hobel et al. [29]. 

A syndrome resembling that of the fetal alcohol syndrome has been described in infants who had been exposed to toluene in utero (54). Of all toluene-exposed infants, 39% were born prematurely and 9% died during the perinatal period 54% were small for gestational age and 52% had continued postnatal growth deficiency 33% had prenatal microcephaly, 67% postnatal microcephaly, and 80% developmental delay. In 83% there were craniofacial features similar to the fetal alcohol syndrome, and 89% of these children had other minor anomalies. The authors suggested that toluene and alcohol have a common mechanism of craniofacial teratogenesis, namely deficiency of craniofacial neuroepithelium and mesodermal components owing to increased embryonic cell death. 

Rauch, S.A., Braun, J.M., Boyd Barr, D., Calafat, A.M., Khoury, J., Montesano, M.A., Yolton, K., Lanphear, B.P. Associations of prenatal exposure to organophosphate pesticide metabolites with gestational age and birth weight. Environ. Health Perspect 120, 1055-1060... 

The risks of exchange transfusion are essentially the same as those described above for massive transfusions, and their magnitude depends on the health of the newborn infant and its gestational age and weight. The transfused blood should be as fresh as possible and should not have been stored for more than 4-5 days. It must be free from antigens that react with antibodies in the maternal plasma. Technical errors involving perforation of the umbilical vein, wrong placement of the cannula, or air embolism are fortunately only rare complications. 

Since lipoprotein lipase activity is reduced in premature babies and babies who are small for gestational age, and since bacterial and viral infections adversely affect lipoprotein lipase activity and can precipitate fat overload, it follows that fat emulsion should be administered with great caution, or even temporarily withheld, in small infants with proven or suspected sepsis (134). 

The early part of the SWHS looked at the relation of pregnancy outcome to maternal TCDD levels measured in serum collected shortly after the explosion. Ninety-seven pregnancies (10.9%) ended as spontaneous abortions. TCDD was associated with a nonsignificant adjusted decrease in gestational age and a 20-50% nonsignificant increase in the odds of preterm delivery. The exposed population also reported symptoms of immune system and neurological disorders however, studies found no link to dioxin. Increases in some forms of cancer found in the exposed population have suggested a link between dioxin and some cancers. 

After estimating fetal exposure, clinicians should consider the potential health effects on the fetus. Potential fetal health effects other than cancer are a function of gestational age and radiation dose (13). The information in Table 4.4 can help physicians advise their pregnant patients, but the table does not provide definitive recommendations. However, clinicians should consider these basic principles in providing advice to pregnant women exposed to radiation ... 

The detection and false-positive rates achievable depend on many factors includmg (1) the test combination chosen, (2) the risk cutoff chosen, (3) the method of dating used to establish gestational age, and (4) the maternal ages of the women being tested. Table 54-3 summarizes the impact of these factors in a hypothetical cohort of women having the maternal age distribution found in the United States in 2000. In the United States, many laboratories use the triple test (AFP, uEj, CG) and a cutoff equivalent to the risk of a 35-year-old woman (1 270 in the second trimester or 1 350 at term). At this risk cutoff and with use of the date of the... 

Figure 54-10 A comparison of the associations between gestational age and the four second trimester maternal serum markers for Down syndrome. For each of the analytes, the median at 15 weeks gestation has been assigned a value of 100%. Each subsequent median is represented as a percentage of that initial median. The marker that has the weakest association with gestational age is dimeric inhibin A (DIA).The strongest associations are found for unconjugated estriol (uEa) and chorionic gonadotropin (CG).The association between gestational age and alpha fetoprotein (AFP) is intermediate.

Gronowski AM, Parvin CA. Prediction of risk for respiratory distress syndrome using gestational age and the TDx FLM II assay. Am J Obstet Gynecol 2003 189 1511-2. 

Uauy R, Mena P. Wegher B. Nieto S, Salem N Jr. Long chain polyunsaturated fatty acid formation in neonates effect of gestational age and intrauterine growth. Pediatr Res 2000 47(1) 127-135. 

Nahata MC, Powell DA, Durrell DE, et al. Effect of gestational age and birth weight on tobramycin kinetics in newborn infants. J Antimicrob Chemother 1984 14 59-65. 

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