Dawson E B, Albers J, McGanity W J
Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston 77550.
Am J Clin Nutr. 1989 Oct;50(4):848-52. doi: 10.1093/ajcn/50.4.848.
Serum zinc and iron concentrations in a group of pregnant teen-agers supplemented with a multivitamin were compared during pregnancy with a group supplemented with a multivitamin containing 18 mg Fe. Serum measurements were at 13 wk of gestational age (prestudy) and during supplementation at 20, 32, and 38 wk, delivery, and 4 and 12 wk postpartum. Hematocrit measurements were used to adjust the measured metal concentrations for the diluting effect of the normal blood-volume increase. The non-Fe-group mean, adjusted serum Zn concentrations showed no change, but the serum Fe decreased to 28% below prestudy concentrations at 38 wk. In contrast, the Fe-supplementation group showed a progressive increase in Fe concentrations to a maximum of 38% above prestudy concentrations at 4 wk postpartum and a 35% decrease from prestudy Zn concentrations during the third trimester. The results of this study suggest that 18 mg Fe/d is adequate supplementation for nonanemic teen-age pregnancy and depresses the serum Zn concentration.
对一组补充多种维生素的怀孕青少年的血清锌和铁浓度在孕期与另一组补充含18毫克铁的多种维生素的青少年进行了比较。血清测量在孕13周（研究前）以及补充期间的孕20周、32周、38周、分娩时以及产后4周和12周进行。血细胞比容测量用于针对正常血容量增加的稀释作用调整所测金属浓度。非铁组经调整后的血清锌浓度平均值无变化，但血清铁在孕38周时降至比研究前浓度低28%。相比之下，铁补充组的铁浓度逐渐升高，在产后4周时最高比研究前浓度高出38%，并且在孕晚期血清锌浓度比研究前降低了35%。本研究结果表明，每日18毫克铁对非贫血青少年孕期来说是足够的补充量，且会降低血清锌浓度。
