What Is an Amniotic Graft?
Chronic wounds, including diabetic foot ulcers (DFUs), venous leg ulcers (VLUs), and pressure injuries, represent a growing challenge across outpatient clinics, mobile wound care providers, and hospital-based teams. As traditional treatments fall short, many clinicians turn to advanced wound care options like amniotic grafts. But what exactly is an amniotic graft? How is it made, and where does it fit in clinical decision-making? Those questions, plus others, we will answer here so that providers, practice managers, care teams, and any other stakeholder in the medical field may have a clear, accurate, and science-based overview for this increasingly common and vital tool.
What Is Amniotic Tissue?
The amniotic membrane is the innermost layer of the three distinct tissue layers, amnion, intermediate, and chorion, that make the placental membrane. During pregnancy, the amnion membrane surrounds and protects the fetus, providing both a barrier and a biochemical support system for development. The amniotic membrane comprises a single layer of epithelial cells, a basement membrane, and collagen-rich extracellular matrix. It is naturally avascular and anti-inflammatory, and it contains structural proteins (collagen types I, III, IV, V, and VII) and growth factors. These characteristics make it a compelling option for tissue coverage in medical applications, especially when processed into a biologic allograft.
Note: Most amniotic grafts used in wound care today are decellularized and dehydrated, meaning they do not contain live cells but instead serve as a biologically compatible scaffold.
How is an Amniotic Graft Made?
Amniotic grafts are made from donated placental tissue following scheduled cesarean and live-birth deliveries. Tissue banks screen donors rigorously, following FDA and American Association of Tissue Banks (AATB) guidelines for eligibility and safety.
The membrane is then processed using various methods, such as:
- Aseptic recovery and preservation
- Dehydration (for room-temperature storage)
- Cryopreservation (to preserve tissue structure and flexibility)
- Powdered or particulate formats
Early development and use of placental membrane in medicine chiefly utilized the amnion membrane, however rapid utilization of all three membranes has produced a larger variety of graft types providing unique characteristics for specialized treatments. Some of these variations include:
- Single-layer (amnion only)
- Dual-layer (amnion and chorion)
- Full-membrane (amnion, intermediate, and chorion)
These products are regulated under Section 361 of the Public Health Service Act, provided they meet criteria for minimal manipulation and homologous use.
What Is the Clinical Purpose of an Amniotic Graft?
Amniotic grafts are used in wound care primarily as protective coverings for hard-to-heal wounds. They do not replace standard of care but are typically introduced when wounds stall in healing. Amniotic grafts are typically used to:
- Provide coverage and protection over chronic wounds
- Support a moist wound healing environment
- Offer a biological scaffold for cell migration and matrix remodeling
A beneficial characteristic for amniotic grafts is that they are non-immunogenic due to their lack of blood vessels and low expression of Human Leukocyte Antigens (HLA), making them suitable for allogeneic use.
Important: These products are not considered drugs or biologics under FDA HCT/P regulations and are not intended to diagnose, treat, or cure any condition. Clinical judgment determines appropriate application.
Where Are Amniotic Grafts Typically Used?
Amniotic grafts are often used by:
- Podiatrists (for diabetic foot ulcers)
- Wound care specialists
- Plastic or general surgeons
- Mobile wound care teams
- Outpatient hospital departments or office-based practices
They are commonly applied to:
- DFUs and VLUs
- Pressure injuries
- Surgical dehiscence
- Non-healing traumatic wounds
The graft is placed directly over the wound bed, secured per protocol (often with a non-adherent secondary dressing), and left in place to resorb or be removed based on product type.
How Do Amniotic Grafts Compare to Other Graft Types?
Amniotic grafts are one of several skin substitute categories. Others include Collagen-based products, synthetic scaffolds, dermal allografts, and blood-derived matrices (e.g., red clot or PRP-based systems). Each has distinct handling, shelf life, and clinical characteristics. Selecting the right graft depends on wound type, provider preference, and coverage considerations. We’ll explore these differences in future posts.
Final Thoughts
Amniotic grafts represent a valuable tool in advanced wound care, especially when conventional treatments fail to produce results. While they are not magic bullets, they offer clinicians a biocompatible, naturally derived scaffold to support the healing process. Understanding what they are, and what they’re not, is the first step in using them responsibly.
