Sivakumar B, Panth M, Shatrugna V, Raman L
National Institute of Nutrition, Indian Council of Medical Research, Hyderabad, India.
Int J Vitam Nutr Res. 1997;67(4):232-6.
Plasma vitamin A responses were examined in 30 low income pregnant women before and after supplementation with vitamin A. In the groups of women who had an initial (at < 20 weeks) plasma vitamin A of less than 30 micrograms/dl retinol, typical changes representing a peak at mid gestation and a significant decline at term were observed. Supplementation with vitamin A tablets equivalent to 1800 micrograms of retinol daily for 12 weeks was able to raise the plasma vitamin A content at term. On the other hand, those women who had an initial plasma vitamin A concentration of more than 30 micrograms/dl did not show any appreciable changes even with vitamin A supplementation. Consistent beneficial effects of supplementation on maternal and cord vitamin A and maternal hemoglobin and progesterone were noted in our previous studies only when the supplementation lasted for 12 weeks and not after 10 weeks. Using these data with dietary intake obtained from other studies, an attempt was made to estimate the requirements of vitamin A during pregnancy. The approximate requirement of 780 retinol equivalents (RE) obtained, is in agreement with earlier recommendations of FAO and Indian Council of Medical Research (ICMR) Expert Committees, but is higher than the recent ICMR recommendations.
对30名低收入孕妇在补充维生素A前后的血浆维生素A反应进行了检测。在初始（孕20周前）血浆维生素A低于30微克/分升视黄醇的女性组中，观察到典型变化，即妊娠中期达到峰值，足月时显著下降。每天补充相当于1800微克视黄醇的维生素A片，持续12周，能够提高足月时的血浆维生素A含量。另一方面，那些初始血浆维生素A浓度超过30微克/分升的女性，即使补充维生素A也未显示出任何明显变化。仅在补充持续12周而非10周时，我们之前的研究才注意到补充对母体和脐带维生素A以及母体血红蛋白和孕酮有持续的有益影响。利用这些数据以及从其他研究中获得的饮食摄入量，试图估算孕期维生素A的需求量。得出的约780视黄醇当量（RE）的需求量与粮农组织和印度医学研究理事会（ICMR）专家委员会早期的建议一致，但高于ICMR最近的建议。
