OBJECTIVES: The purpose of this study was to determine the impact of iron status on cadmium dose among pregnant women. METHODS: Iron status and cadmium concentration in blood, urine, and placenta were determined among women followed for 2 years from early pregnancy. RESULTS: Blood cadmium and urinary cadmium were correlated with iron status throughout the study period. Urinary cadmium increased longitudinally among women with exhausted iron stores during their pregnancy. The increase in urinary cadmium with age was more pronounced in multiparous than in nulliparous women. CONCLUSIONS: Iron deficiency during pregnancy leads to increased cadmium absorption and body burden. Multiparous women exhibit additional increases with increasing age.
OBJECTIVES. We sought to describe prenatal care use in the United States and in three European countries where accessibility to prenatal care has been reported to be better than it is in the United States. METHODS. We analyzed the 1980 US National Natality Survey, the 1981 French National Natality Survey, a 1979 sample of Danish births, and a survey performed from 1979 to 1980 in one Belgian province. RESULTS. The proportion of women who began prenatal care late (after 15 weeks) is highest in the United States (21.2%) and lowest in France (4.0%). This contrasts with the median number of visits, which is greater in the United States (11) than in Denmark (10) or in France (7). Across all maternal ages, parities, and educational levels, late initiation of prenatal care is more frequent in the United States, and median number of visits in the United States is equal to or higher than that in the other countries. CONCLUSIONS. In countries that offer nearly universal access to prenatal care, women begin care earlier during pregnancy and have fewer visits than women in the United States.
OBJECTIVES: This study examined the effect of maternal smoking during pregnancy on infant body proportion. METHODS: The ponderal index, defined as birthweight divided by crown-heel length cubed, was examined in 207,607 infants from the Swedish Medical Birth Register for 1991 and 1992. RESULTS: Infant ponderal index was used as the outcome variable in an ordinary least squares continuous regression, which included early pregnancy smoking status, gestational age, and birthweight among the predictors. Ponderal index increased by 0.030 (+/- 0.0014) among infants of moderate smokers and by 0.040 (+/- 0.0017) among infants of heavy smokers, showing a dose response. CONCLUSIONS: Smoking differentially alters the trajectory of weight vs length growth in the fetus.
OBJECTIVES: We sought to determine precise estimates of infant mortality rates and to describe overall trends in infant mortality in Greenland and Denmark from 1973 to 1997. METHODS: We analyzed data from population-based registries of all live-born infants in Greenland and Denmark to calculate infant mortality rates from 1973 to 1997. RESULTS: Between the periods of 1973-1977 and 1993-1997, neonatal mortality rates in Greenland declined from 20.9 per 1000 live-born infants to 15.7, and postneonatal mortality rates declined from 20.9 per 1000 to 5.9. Infant mortality rates were significantly higher in Greenland than in Denmark, and the excess mortality was uniformly distributed over all birthweight percentiles. In Greenland, the risk of infant death was significantly lower if the mother was born outside Greenland. CONCLUSIONS: Postneonatal mortality rates in Greenland have decreased significantly during the past 25 years, but little progress has been made in decreasing neonatal mortality rates. Disparities exist among children with different maternal origins.