I found out by searching online that wild yam might be able to help deal with morning sickness. But dunno if it will work or whether it is safe, must definitely ask the doctor first.
WILD YAM- VP-K+(in excess)
Actions: nutritive tonic, aphrodisiac, rejuvenative, diuretic, antispasmodic, analgesic
Indications: impotency, senility, hormonal deficiency, infertility, colic, nervous excitability, hysteria, abdominal pain and cramps, nausea, vomiting, morning sickness
The most common use of wild yam is for the hormonal effects, as it contains DHEA, a hormone precursor. This constituent has usefulness for both men and women, as it can be made by the body into many other hormones, but it does have a particular slant towards progesterone, and so is especially useful for women. These progesterone compounds are also used for exhausted adrenal conditions, and it is comparable to licorice in that effect and its effect on balancing blood sugar levels. Also used for digestive system problems of a bilious or gaseous nature. Its alkaloid constituents act as strong relaxants to the stomach muscles and nerves, and so can be very useful in nausea, cramping, and vomiting. Stong rejuvenative powers. Increase semen, milk and other horomal secretions, and increases body weight, tonic for female reproductive system. Soothing and harmonizing effect on digestive organs.