In general, an approximately 30 lb weight loss is noticeable in the face and neck. If you were planning on losing 10 lbs, I would say that it would not matter whether you did Ultherapy now or later. If you are planning on losing 20 lbs, I would consider waiting until after you have lost all the weight first. If you are planning on losing 30 lbs, I would definitely recommend waiting.
The additional weight loss may affect the appearance of your face and neck in the form of volume loss, as well as sagging skin. It makes more sense to treat these areas once you’ve achieved your target weight than to do it half way through your weight loss. Imagine having a treatment now and being happy with your results, only to develop more sagging as a result of additional weight loss. In addition, addressing your face and neck after your complete weight loss also allows your physician to tailor your treatment to give you the best results possible. Hope this helps! Good luck!
Dr.Sunder