Malone J I
Clin Perinatol. 1975 Sep;2(2):295-307.
A pregnant woman who has adequate nutrition available in the form of a standard diet will provide the vitamins required by the fetus for normal development. Active transport of the water-soluble vitamins plus easy oral absorption after birth insure nutritional sufficiency at any gestational age. The fat-soluble vitamins which have a much slower transfer rate as the result of facilitated diffusion do not achieve the same degree of storage in the developing fetus. Thus, the premature infant who has decreased stores and who may have impaired oral absorption initially may become deficient in a fat-soluble vitamin (A, D, E, K) during the first 4 to 6 weeks of life. Oral or possibly parenteral supplementation following birth, however, would seem more appropriate than subtoxic doses administered to the mother prenatally.
以标准饮食形式摄入充足营养的孕妇会为胎儿正常发育提供所需的维生素。水溶性维生素的主动转运以及出生后易于口服吸收可确保在任何孕周都有充足的营养。由于易化扩散，脂溶性维生素的转运速度要慢得多，在发育中的胎儿体内无法达到相同程度的储存。因此，储存量减少且最初口服吸收可能受损的早产儿在出生后的头4至6周可能会缺乏脂溶性维生素（A、D、E、K）。然而，出生后进行口服或可能的肠外补充似乎比产前给母亲服用亚中毒剂量更为合适。
