Medically reviewed by Anita Sadaty, MD Progesterone is a naturally occurring hormone that helps prepare the lining of your uterus for pregnancy. Progestin is any natural or man-made substance that has ...

"Some birth control is monophasic — meaning it's ... in the cycle without disrupting the hormone increase. However, triphasic pills increase your hormone dosage and starting your period in ...

In Demand from the Start The birth control pill was the ... from the market and biphasic and triphasic oral contraceptives were introduced. These low-dose pills varied the amount of progesterone ...

However, their effect on athletic performance is unclear. Objectives: To examine the effects of a moderate dose, triphasic oral contraceptive on measures of athletic performance in highly trained ...