If that information helps anyone, they are welcome to it. Because of the excellent results in my patients, I have stuck to that delivery system and therefore know little of the other products on the market. Since absorption through mucosa is more rapid and and more efficient than through the dermis, I would suspect that its progesterone effects are more rapid than the cream. Most of my patients through the years are content to use the cream, especially because of its obvious benefit to skin where applied. Oestradiol, for instance, given as a trans-dermal patch containing 0.05 mg applied twice weekly is equivalent to oral doses of 1 mg daily.
Similar efficiency occurs with testosterone and progesterone.
In applying progesterone-containing cream, I recommend using the largest possible areas of relatively thin skin, rotating among various skin sites daily for maximum absorption. Skin sites recommended are the inner aspects of the arms and thighs, the face and neck, the upper chest and the abdomen. In dermal transport, progesterone is first absorbed into the subcutaneous fat layer and then passively diffused throughout the body via blood circulation. Initially, in progesterone-deficient patients, much of the progesterone is absorbed into body fat. With continued use, fat levels of progesterone reach an equilibrium such that successive doses of progesterone result in increased blood levels and stronger physiological effects.