Catherine Middleton, the Duchess of Cambridge, who is in her early stages of pregnancy, is undergoing hypnotherapy to help her overcome problems related to morning sickness.

The 31-year-old Duchess, who is expecting her first child in July, has been ordered by her doctors to rest as much as possible, after being released from the King Edward VII last month. Kate Middleton was diagnosed with Hyperemesis Gravidarum (acute morning sickness), which is a "potentially serious" ailment causing vomiting and a bodily reaction against intake of food and liquids. This sickness is commonly found in pregnant women carrying twins but an earlier release from St James' Palace has confirmed the Duchess is not expecting twins.

"Kate still looks at food and feels nauseous. She's been plagued with that feeling you have when you've had food poisoning and your stomach's shrunk," her friend Jessica Hay has told Australia's New Idea magazine.

According to Hay, the pregnant Duchess is on a diet consisting of wholesome meals and snacks with include food such as avacados, berries, oatmeal and broccoli.

"She finds it very hard to eat a full meal and gets full very quickly. The hypnotherapy is taking away any negative thoughts connected with food from the morning sickness, and replacing them with cravings for healthy, nutritious food."

She has also reportedly taken up Pilates to keep fit during her pregnancy and is keeping a regular schedule of three sessions a week.

"All in all, Catherine's very happy. With so much family around her and William, they're starting to enjoy the pregnancy after such a traumatic start," she added.

Kate Middleton has also taken a break from royal duties for a while, and was last seen public on a visit to Starbucks in Kensington, accompanied by a security guard and her cocker spaniel Lupo.

Adding on, her brother-in-law, Prince Harry has also spoken about his excitement over the good news.

"Obviously I'm thrilled for both of them," Prince Harry, who serves as an Apache helicopter Pilot said in a pre-taped interview at the end of his four-month military tour in Afghanistan, "It's about time. I can't wait to be an uncle."

"I spoke to my brother and her, and they're both very well and both very happy obviously," he added.

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