快樂小藥師 Im pharmacist nichts glücklich

主要理由有以下：

1.The placenta transmits lipids and vitamin K relatively poorly.
2.The neonatal liver is immature with respect to prothrombin synthesis.
3.Breast milk is low in vitamin K, containing about 2.5 μg/L (cow's milk contains 5000 μg/L).
4.The neonatal gut is sterile during the first few days of life.

相關內容可以參考Merck Manual

以上內容感謝彰基藥師bao yuan的分享