The Viability Of Human Embryos After Transport In A Dry Shipper Between Assisted Conception Laboratories

Problems during transport have been described in the l i t e ra tu re f o r human embryos desp i t e specifically-designed dry shippers, including failure of the dry shipper and poorer outcomes using the transported material. The aim of the present study was to examine the performance after thawing of embryos imported to the Hollywood Fertility Centre in a dry-shipper (MVE SC 4/2V). A total of 926 embryos were imported for 154 women, and a total of 689 have been thawed to date. Thaws were performed using methods that matched the freezing protocols, and the outcomes were compared with a parallel group of women treated at the Hollywood Fertility Centre whose frozen embryos had remained in-house. The survival of thawed imported embryos was significantly reduced for zygotes (69.8% vs 84.6%) and blastocysts (51.7% vs 73.7%) but not early cleavage embryos (60.8% vs 65.7%). However, culture to Day 5/6 of either thawed zygotes or early cleavage embryos gave blastocyst utilization rates for imported embryos that were similar to or better than in-house embryos. The replacement of embryos at an appropriate stage of the cycle showed pregnancy rates that were similar for the imported embryos compared to the in-house embryos. It is concluded that transported human zygotes and blastocysts do not survive as well after thawing compared to equivalent embryos stored in-house. However, the ability of all surviving embryos to grow in vitro and implant is not compromised.