Medicinal plant used for extraction of steroids for oral contraceptives preparation is

The medicinal plant used for extraction of steroids for oral contraceptive preparation is Medicinal Yam.
Medicinal yams are robust, perennial, branched, climbers native to tropical Asia, Africa and South America. The underground rhizomes or tubers contain alkaloids like diosgenin, and pannogenin and are used for the synthesis of antiarthritic, anti-inflammatory, antifertility and anabolic drugs.