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A study on the preservation of fresh amniotic membrane.

OBJECTIVE
To establish the standard preservation methods of fresh amniotic membrane for clinical use.


METHODS
Human placentas were collected aseptically from selective caesarean sections in normal women in time. Amniotic or placental membrane were peeled and preserved in N. S, P. B. S or DMEM at 4 degrees C or cultured in DMEM at 37 degrees C, 5% CO2. Trypan-blue staining, light and electronic microscopy were observed every six hours after preservation.


RESULTS
Seventy percent of amniotic epithelial cells survived after preservation in N.S for 6 hours, PBS 12 hours, DMEM 24 hours and 1 week in tissue culture. The amount of living epithelial cells maintained in placental membrane preservation was less than that in amniotic membrane preservation at the same time (t-test, P < 0.01). No collagen degeneration was found during preservation.


CONCLUSION
Preservative solution and time will affect the maintenance time of fresh amniotic membrane greatly. Fresh amniotic membrane should be preserved within 6 hours in N. S, 12 hours in P. B. S, 24 hours in DMEM at 4 degrees C and 1 week in tissue culture for clinical use.