some progesterone facts

Progesterone is a steroid hormone involved in the female menstrual cycle, pregnancy (supports gestation) and embryogenesis of humans and other species. The use of progesterone and its analogues have many medical applications -- both to address acute situations, and to address the long-term decline of natural progesterone levels. Because of the poor bioavailability of progesterone when taken orally, many synthetic progestins have been designed. Progesterone is poorly absorbed by oral ingestion unless micronised and in oil, or with fatty foods; it does not dissolve in water. Progesterone can be given by injection, but because it has a short half-life they need to be daily. Implants, for a longer period, are also available.