Table 1.

Biomaterials in reproductive tissue engineering and their applications.

Classification	Merits and demerits	Biomaterials	Applications	Ref.
Synthetic polymers	Inexpensive and can be manipulated easily; tunable mechanical properties and high malleability; lack of or limited biocompatibility Foreign body response; adverse immunologic reactions; lack of adhesion to living tissues	PLA	Combined with autologous chondrocytes to construct penile prostheses	[22]
		PGA	Combined with cells to reconstruct the smooth muscle tissue of the cavernous body	[23]
		PDMS	Coculture of embryonic stem cells and testicular cells; Microfluidic devices	[26,90]
		PLGA	In vitro spermatogenesis of immature spermatogenic germ cells	[27]
		PEG	3D follicular culture	[92]
Natural polymers (hydrogels)	High-water content; excellent biodegradability and biocompatibility; environmental stresses similar to tissue; can be easily loaded with other factors; maintain the 3D culture environment; ensure the effect of cell–cell interactions; Insufficient mechanical strength	Hyaluronan-based hydrogels	In vitro maturation of follicles	[29]
		Gelatin-based hydrogel	Constructing placental barrier models	[31]
		Soft agar hydrogel	Coculture of spermatogonia and somatic cells	[81]
		Alginate-based hydrogels	In vitro follicular culture; in vivo transplantation of isolated preantral follicles and ovarian cells; 3D culture system for testicular cells	[32,54]
		Fibrin hydrogels; fibrin-alginate hydrogels; fibrin-collagen composites	Primordial follicle transplantation	[57,58]
		Collagen-based hydrogel	In vitro oocyte maturation of ovary follicles	[51]
		Matrigels	Generation of functional spermatids from human SSCs in vitro; testicular, ovarian, and endometrial organoids	[[40], [41], [42], [43], [44], [45],55]
Natural polymers (scaffolds)	Porous structure, good tissue integration; can be loaded with cell growth factors and drugs; improve angiogenesis Insufficient mechanical strength	Collagen scaffolds	Loaded with human umbilical cord-derived mesenchymal stem cells/bone marrow mesenchymal stem cells for endometrial regeneration	[28,117]
		Alginate-based macroporous scaffolds	Culture and growth of primitive follicles	[126]
		Gelatin-based scaffolds	Create a bioprosthetic ovary; endometrial repair; functional reconstruction of injured corpus cavernosa	[30,59,119]
Acellular matrices	Retention of the bioactive matrix; Structural integrity with better mechanical performance Need improvements in terms of the morphology and precise structure of the original tissue after decellularization; cell filling rate during the recellularization process needs to be improved	Acellular porcine small intestinal submucosa graft	Cervicovaginal reconstruction	[127]
		Corpora collagen matrices	Functional restoration of the penis	[62,66]
		Autologous cartilage rods	Penile prostheses	[67]
		Amniotic membrane	Penile reconstruction (treatment of Peyronie's disease)	[128]
		Acellular uterus	Recellularized in vitro with primary uterine cells (Bioengineered uterine tissue)	[[68], [69], [70], [71]]
		Bovine pericardium	Potential scaffold for testicular repair	[72]
		Ovarian scaffolds	Artificial ovaries	[63,64]
		Decellularized placental scaffold	3D dynamic culture of mouse embryonic fibroblasts	[70]
		Acellular testis	Testicular organoid construction	[[73], [74], [75]]