Abstract:

To evaluate the results of vitrified human unfertilized oocytes and discarded embryos by selfmade modified Hemistraw or Cryoleaf. Methods98 unfertilized oocytes and 76 discarded embryos, which derived from conventional IVF or ICSI cycles, were randomly divided into group A（Cryoleaf）and B（modified Hemistraw）. After thawing, the frozen samples were continuously observed. The survival rate of unfertilized oocytes, the 24?h survival rate  and the cleavaged rate were measured. Also the survival rate of embryos, the keeping survival rate of 24?h and the blastocyst rate were calculated. ResultsIn group A, 43 unfertilized oocytes were vitrified, of them 29 (67.4%) survived, 23(53.5%) kept survival for 24?h, and 3(7.0%) were cleavaged. In group B, 55 unfertilized oocytes were vitrified, of them 31(56.4%) survived, 25 (45.5%) survived for 24?h, and 1 (1.8%) had cleavage. The above indexes had no statistical significances between the two groups(P＞0.05). 39 and 37 discarded embryos were respectively vitrified by Cryoleaf and modified Hemistraw, the survival rate of embryos, the 24?h survival rate and the blastocyst rate showed no significant differences (74.4% vs 89.2%, 71.8% vs 89.2%, and 12.8% vs 2.7%, P＞0.05).ConclusionThe modified Hemistraw may be an alternative  method to Cryoleaf due to its widespread resource, low price and similar survival rate of vitrification.

Key words: Ovum; Embryo; Vitrification; Carrier; Cryopreservation