Efficacy and Safety of BtH Body 2.2% (Injectable Hyaluronic Acid) in Volumizing and Contouring Large Areas of the Body: Prospective Clinical Investigation.

Inclusion Criteria: * Adults (≥18 years old) * Presence of extensive body areas (gluteal region, thighs, or abdomen) showing aesthetic concerns such as: * loss of volume * flaccidity * contour asymmetries * skin irregularities * cellulite * Willingness and ability to comply with all study visits and procedures. * Sufficient predisposition and capacity, in the investigator's judgment, to complete study questionnaires. * Negative urine pregnancy test for women of childbearing potential at required visits. * Use of appropriate contraception for women of childbearing potential, as outlined in the protocol. Exclusion Criteria: * Allergy or sensitivity to any of the components of the investigational product. * Planned pregnancy or breastfeeding. * Presence of active pathology or bacterial, fungal, or viral infection in or near the area to be treated, or undergoing active treatment for these conditions * Presence of clinical signs of inflammation in or near the area of interest or undergoing active treatment for these conditions. * Individuals with a known tendency to develop hypertrophic scars or keloids. * Individuals undergoing anticoagulant therapy. * Presence of volumetric defects that are too large and require surgical procedures, in the opinion of the healthcare specialist. * Subjects who have undergone any interventional cosmetic procedure in the 6 months prior to entering the study or during the study, such as laser, radiofrequency, electrotherapy, intradermal fillers, lipotransfer, thread lifts, platelet-rich plasma, among others. * Subjects with disproportionate expectations regarding the expected results of treatment. * Subjects with any of the following contraindications: Chronic conditions (Active autoimmune diseases (or under immunosuppressive treatment): Systemic lupus erythematosus, scleroderma, active rheumatoid arthritis, or Sjögren's syndrome; Active infections or inflammatory processes in the area of application: Herpes simplex, pustular acne, folliculitis, or cellulitis; Uncontrolled coagulation disorders or use of anticoagulants; Immunocompromised patients (due to disease or treatment): Uncontrolled HIV, chemotherapy, systemic corticosteroids, or organ transplantation) and medications (medications that increase the risk of bleeding or bruising: anticoagulants (warfarin or acenocoumarol) and antiplatelet agents (salicylic acid, prasugrel, or ticagrelor), immunosuppressants and biologics (prolonged systemic corticosteroids such as methotrexate, azathioprine, cyclosporine, mycophenolate mofetil, biologic drugs such as infliximab or adalimumab), systemic retinoids (isotretinoin), antidepressants, oral antidiabetics/insulin)