An increasing proportion of infants weigh more than 4000 grams at birth

BACKGROUND: To investigate how mean birthweight has changed in the past decade, and to describe changes in the proportion of infants with a birthweight above 4000 grams (g). METHODS: We analyzed data on 43,561 singleton infants born between 1990 and 1999 at Aarhus University Hospital, Denmark. Information on birthweight, gestational age, stillbirths, malformations, mode of delivery, prelabor intervention, and maternal diabetes was obtained from birth registration forms. RESULTS: For all infants mean birthweight increased by 45 g (95% CI: 20-70 g) from 3474 g in 1990 to 3519 g in 1999. For infants born at term the mean increase was 62 g (95% CI: 41-83 g). During the same period the percentage of infants born with a birthweight above 4000 g increased from 16.7% in 1990 to 20.0% in 1999 (p<0.05). Simultaneously we found a decrease in gestational age and an increase in the frequency of induction of labor. There was a statistically significantly higher risk of giving birth to an infant with a birthweight above 4000 g throughout the decade, when gestational age and prelabor intervention was taken into account. CONCLUSIONS: In Denmark mean birthweight has risen during the past decade independently of gestational age and prelabor intervention. Simultaneously the risk of having a baby with a birthweight above 4000 g has increased. Further studies on potential risk factors for birth of large infants are needed.     

Exposure to tobacco smoke in utero and the risk of stillbirth and death in the first year of life

The authors examined the association between exposure to tobacco smoke in utero and the risk of stillbirth and infant death in a cohort of 25,102 singleton children of pregnant women scheduled to deliver at Aarhus University Hospital, Aarhus, Denmark, from September 1989 to August 1996. Exposure to tobacco smoke in utero was associated with an increased risk of stillbirth (odds ratio = 2.0, 95% confidence interval: 1.4, 2.9), and infant mortality was almost doubled in children born to women who had smoked during pregnancy compared with children of nonsmokers (odds ratio = 1.8, 95% confidence interval: 1.3, 2.6). Among children of women who stopped smoking during the first trimester, stillbirth and infant mortality was comparable with that in children of women who had been nonsmokers from the beginning of pregnancy. Conclusions were not changed after adjustment in a logistic regression model for the sex of the child; parity; or maternal age, height, weight, marital status, years of education, occupational status, and alcohol and caffeine intake during pregnancy. Approximately 25% of all stillbirths and 20% of all infant deaths in a population with 30% pregnant smokers could be avoided if all pregnant smokers stopped smoking by the sixteenth week of gestation.     

Virus-mediated oncolysis of thyroid cancer by a replication-selective adenovirus driven by a thyroglobulin promoter-enhancer region

CONTEXT: Currently, there is no effective treatment for iodine-resistant thyroid cancers. OBJECTIVE: As a new approach to treatment, the efficacy of replication-selective, human thyroglobulin (TG) enhancer and promoter-driven, adenovirus (AdhTGEP)-mediated oncolysis was investigated using two well-differentiated thyroid cancer cell lines, XTC (TG positive) and FTC-133 (TG negative), and other control tumor and nontumor cell lines (all TG negative). DESIGN: A cohort study design was used. SETTING: The study setting was laboratory bench-top experiments. SUBJECTS/PARTICIPANTS: In vitro TG-expressing and nonexpressing thyroid cell culture lines, nonthyroid tumor cell lines, as well as preclinical thyroid tumor-bearing mice were studied. INTERVENTION: Adenoviral infection of cell lines was determined by immunohistochemistry, selective replication by one-step growth assays, and cytotoxicity by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulphophenyl)-2H-tetrozolium (MTS) assay. In vivo tumor growth inhibition was determined by a single intratumoral injection of 1 x 10(9) plaque-forming units AdhTGEP, AdLacZ (control virus), or PBS to 50- to 75-mm(3) tumors. XTC cells showed intense immunohistochemical staining, whereas FTC-133 and all other control cell lines showed minimal staining for viral infection with AdhTGEP. MAIN OUTCOME MEASURES: Cell survival and tumor growth inhibition after adenoviral infection were the main outcome measures. RESULTS: One-step growth assays showed at least a more than 60-fold titer of AdhTGEP in XTC than in FTC-133 cells. Cytotoxicity assays showed approximately 68% cell kill in XTC and minimal cell kill in FTC-133 and all other control cell lines at a multiplicity of infection of 250. There was significant in vivo growth inhibition of AdhTGEP-treated XTC tumors (67 +/- 49 mm(3)) compared with AdLacZ-treated XTC (228 +/- 45 mm(3); P < 0.01), PBS-treated XTC (372 +/- 70 mm(3); P < 0.001), or AdhTGEP-treated FTC-133 tumors (598 +/- 168 mm(3)). CONCLUSION: Replication-selective virus-mediated oncolysis is a potential therapy for recurrent, well-differentiated, TG-secreting thyroid cancer that is unresponsive to standard treatment.