Vitamin K2 has a higher rate of transport across
the placenta than vitamin K1.38 When mothers receive injections of vitamin K2, the placenta rapidly accumulates it and then releases it slowly to the fetus over time.39 Vitamin K1 is found in leafy greens while vitamin K2 is found in fermented foods and grass - fed animal fats — especially natto, goose liver, cheese, and to a lesser extent butter and egg yolks.40