Underwood B A
WHO Nutrition Unit, World Health Organization, Geneva, Switzerland.
Am J Clin Nutr. 1994 Feb;59(2 Suppl):517S-522S; discussion 522S-524S. doi: 10.1093/ajcn/59.2.517S.
Early fetal vitamin A supplies must be regulated to avoid teratogenic consequences from too little or too much. Late in gestation, adequate maternal vitamin A status is important for newborn reserves and for sustaining adequate breast-milk concentrations. Vitamin A supplements are not needed for most pregnant women in Western countries who consume the recommended dietary allowance during their reproductive years. Increased consumption of vitamin A-rich foods can meet increased needs during lactation. Women in developing countries whose habitual intakes are near basal needs should receive an additional 100 micrograms retinol equivalents (RE) during pregnancy and 300 micrograms RE during lactation. Supplements not above 3000 micrograms RE (10,000 IU) daily are safe for fertile women where circumstances preclude obtaining the needed increment through diet. The first postpartum month is the only safe period during which to provide deficient lactating women with a single high-dose supplement to benefit the mother and breast-feeding infant for several months.
必须对胎儿早期的维生素A供应进行调节，以避免因摄入过少或过多而产生致畸后果。在妊娠后期，孕妇充足的维生素A状况对于新生儿储备以及维持母乳中足够的维生素A浓度非常重要。在西方国家，大多数在生育期摄入推荐膳食营养素供给量的孕妇不需要补充维生素A。增加富含维生素A食物的摄入量可以满足哺乳期增加的需求。在发展中国家，那些日常摄入量接近基本需求的妇女，在孕期应额外补充100微克视黄醇当量（RE），在哺乳期应额外补充300微克视黄醇当量。在因情况所限无法通过饮食获得所需增量的情况下，对于育龄妇女而言，每日补充量不超过3000微克视黄醇当量（10,000国际单位）是安全的。产后的第一个月是唯一的安全期，在此期间可以为维生素A缺乏的哺乳期妇女提供单次大剂量补充剂，以使母亲和母乳喂养的婴儿在几个月内受益。
