People with oval face can wear almost any types of glasses. Personally, you shall be care to choose lenses if you want to get a pair of good look eyeglasses. Since you have serious myopia, you shall choose high index lenses so as to get thinner prescription lenses to fit for our eyeglasses. As for the eyeglasses frame, a pair of simple designed black eyeglasses frame will be good for you.
Square and rectangular frames add contrast to the curved lines of the oval face. Other shapes are fair game as well, just be sure to keep scale in mind. Ovals biggest downfall is a frame that is too small or too large, throwing off the natural balance of the face.