I got 2 Sculptra sessions - after first session I lost five pounds and second maybe 2lbs, will it still work?

Even though you lost some weight, Sculptra has not been affected. It will still continue to stimulate your skin to produce more collagen, giving you volume and elasticity.
However, often when we lose weight, we lose more facial fat than we wanted, so if you lost weight in your face, the amount of Sculptra you received may no longer be sufficient to give you the look you want. If you look gaunt, then yes, I’d recommend a third session. If you like the way you look after the weight loss, then there is no need to do a third session.  Please find a board-certified dermatologist to do any further Sculptra injections to ensure beautiful and safe results.

Sculptra works by making collagen. Overall nutrition is important and lack of certain macronutrients and calories will affect the outcome. Also, avoid smoking as it shuts down collagen production. Good luck. Dr. Aldo

Thank you for sharing your question.  Weight loss will not impact your Sculptra results but if you tend to lose volume in the face when you lose weight you may require additional vials of treatment to maintain/add the volume that you originally had.  Hope this helps.