It grows in Mexico, Canada and the United States. Wild yams contain a sapogenin called diosgenin. Diosgenin is a precursor to the hormone progesterone. Yams do not. Wild yam extract has been shown to reduce the fatigue, inflammation, pain and stress related to menstruation.
Wild yam is a valuable antispasmodic, therefore is also helpful in relieving menstrual cramps.
In pregnant women, it is prompt in relieving the nausea associated with morning sickness and can help prevent miscarriage. It has also been used to relieve the after pains of childbirth. Wild yam has been used by some as a natural contraceptive. When taken over a long period, it causes a temporary sterility that ends when the women discontinues wild yam supplements. Caution should be used when using wild yam as a contraceptive because it may not be effective in preventing pregnancy.