Can tissue expanders be used for labia MAJORA to stretch the skin back out to normal?

Tissue expanders work best when the tissues have a good blood supply and are elastic. It seems that your tissues don't have a good blood supply and are not elastic. This is a consequence of your previous surgeries. The predictable risks of proceeding under these conditions would be significant pain, wound dehiscence, infection, and capsular contracture. In brief, it's not a good option for you and might even worsen your situation. Fat injections done over several sessions spaced months apart should not be dismissed as a viable option. Also, it is possible to improve vaginal gaping with a perineoplasty without the need to operate on the labia majora.

Q: Is it possible to expend the labia majora skin for esthetic and functional improvements?
A: I agree with both advisors, Dr. Marko Pelosi III and Dr. Michael P. Goodman, that skin tissue is possible; however, Your problem is not only related to the skin of the labia majora but under the skin is the adipose sac, has also been partially removed. The adipose sac, I discovered and published in the mainstream, reputable journal (Ostrzenski et al. Arch Gynecology Obstet 2016 Sept;294(3):549-554). Resection of this anatomical structure causes flattening of the labia majora.
What type of surgery can help you? It is not a procedure for vaginal gaping, as Dr. Marko Pelosi III suggests in his surgical video, which is not an exact procedure that should be offered for this condition.
Your corrective surgery for labia majora falls into the following steps:
1. Labiolysis (surgical separation of the fusion between the labia majora, intralabial crease, and labia minora (please see my clinical-scientific article (Ostrzenski A. Ann Plast Surg. 2019 Nov;83(5):558-567).
2. The labia majora skin expansion should be considered for accommodating the adipose sac and fat transplant into the sac (not centrifuged fat). The sac must be open, and then after the successful fat transplant, it must be closed
3. Labiopexy is a reconstruction of the structure (the Colles’ fascia) on which the labia majora rest. To the same degree, this operation will rebuild the natural shape of the labia majora. My study results on this topic were published in the medical literature, and you and your prospective doctor can get this article online (Ostrzenski A. Aesthetic Plast Surg. 2014 Jun;38(3):554-60).I concentrated predominantly on the labia majora because your question concerned this aspect of your external genitalia. However, other esthetic problems should be addressed if you choose to do so.
With regards,Prof. Dr. Adam OstrzenskiUSA

Tissue expanding devices are available, but may need to be specifically adapted for use under the skin in the area of the labia majora, towards the goal of later insufflating a fat product in order to
"re-build" modest sized labia majora. (See "Tissue expanders; review of indications, results and outcome during 15 years' experience" by Karimi et al in the Journal of Burns in 2019.) If you wish to research this, do a Google search using the key words "tissue expanders, Pubmed" and you will get real usable information from the medical literature. After full surgical healing and tisssue expanding, most likely the best material for expansion would be micronized nanofat + PRP (platelet-rich plasma.) Best of luck in your quest! Michael P Goodman, MD, FACOG, IF, AAACS. Revision Specialist, Davis, CA, USA