We examined the relation between the vitamin A status of Spanish women during pregnancy and concentrations of vitamin A in breast milk. The subjects were 57 healthy, lactating women aged 18-35 y. Vitamin A intake was determined during the third trimester of pregnancy by using a 5-d dietary record that included a Sunday and by recording the quantities provided by supplements. HPLC was used to determine vitamin A concentrations in subjects' serum during the third trimester, in transitional breast milk (on days 13-14 of lactation), and in mature breast milk (on day 40). During the third trimester, 33.3% of subjects had vitamin A intakes from diet and supplements < 800 microg/d, the recommended value. These subjects had serum and breast milk vitamin A concentrations that were significantly lower than those of subjects who consumed greater quantities of the vitamin. Furthermore, subjects with serum vitamin A concentrations < 1.05 micromol/L during the third trimester (22.8%) had lower mean (+/- SD) concentrations of the vitamin in mature breast milk than did subjects with higher serum concentrations (1.8 +/- 1.2 micromol/L compared with 2.6 +/- 0.8 micromol/L; P < 0.05). These results show that vitamin A intake and serum vitamin A concentrations during pregnancy influence the composition of breast milk. Given that 12.3% of subjects had < 1.40 micromol vitamin A/L in mature breast milk, it seems advisable to follow and, if necessary, improve vitamin A status during pregnancy and lactation.

No abstract

Thiamin deficiency remains an important public health problem in some populations. The aim of the present investigation was to study thiamin status during the third trimester of pregnancy and its influence on the concentration of this vitamin in transition (days 13 -14 of lactation) and mature breast milk (day 40 of lactation) in a group of Spanish women. The pregnancies and lactation periods of fifty-one healthy women 18 -35 (mean 26·7 (SD 3·7)) years old were monitored. Vitamin intake during the third trimester was determined by recording the consumption of foods over 5 d and of the quantities provided by dietary supplements. Thiamin status during this stage of pregnancy was determined by measuring the activation coefficient of erythrocyte transketolase (a-ETK). Milk thiamin content was estimated (in 41% of the subjects) by oxidizing thiamin to thiocrome and measuring fluorescence. Subjects with thiamin intakes above that recommended (group H) had more satisfactory serum a-ETK coefficients (1·01 (SD 0·19)) than did those with lower intakes (group L) (1·21 (SD 0·30); P,0·05). Mature milk thiamin concentrations were significantly higher in group H subjects (0·59 (SD 0·44) mmol/l) than group L subjects (0·25 (SD 0·07) mmol/l). Subjects with a-ETK coefficients . 1·25 in the third trimester had significantly lower mature milk thiamin concentration (0·31 (SD 0·10) mmol/l) than did subjects with more satisfactory a-ETK levels at this time (0·55 (SD 0·42) mmol/l; P, 0·05). The thiamin status of women can be improved since 25·5% of subjects took less than that recommended and 13·7% showed signs of severe deficiency (a-ETK .1·25). The influence of maternal thiamin intake on a-ETK coefficients and on mature breast milk thiamin concentration is confirmed.

If the concentration of antioxidants (vitamin C) in smokers' breast milk is also lower, this might aggravate the peroxidation problems of their newborn.

The estrogenic compound diethylstilbestrol (DES) is widely studied because of its potential endocrine disruption effects. The prohibition of the use of diethylstilbestrol as a growth promoter has not been enough to ensure the total disappearance of this compound from environmental matrices. Due to the low levels of DES present in the environment, preconcentration and clean up methods are necessary for its analysis. This paper describes the synthesis and use of a molecularly imprinted polymer (MIP) as sorbent for on-column solid-phase extraction of DES from aqueous samples. The selectivity of the DES-MIP was evaluated towards several selected estrogens such as hexestrol (HEX), estrone (E1), estriol (E3), estradiol (E2) and ethynylestradiol (EE2). HPLC-DAD was used to quantify all analytes at 230-nm wavelength. The method has been successfully applied to the analysis of DES in spiked river and tap water samples, with recoveries of 72% and 83% respectively.