Impact of the size of zona pellucida thinning area on vitrified-warmed cleavage-stage embryo transfers: a prospective, randomized study.

Purpose: The aim of this study was to determine if the size of zona pellucida thinning area by laser assisted hatching could affect the rates of pregnancy and implantation for vitrified-warmed embryo transfers at the cleavage-stage.

Methods: A total of 120 vitrified-warmed cleavage-stage embryo transfers were randomly assigned to either quarter or half of zona pellucida thinning group.

Results: The rates of clinical pregnancy (46.

Case report: successful delivery following the transfer of a human re-vitrified day-7 spontaneously hatched blastocyst developed from vitrified cleaved embryos.

Purpose: To report a successful delivery after the transfer of a re-cryopreserved day-7 hatched blastocyst.

Methods And Results: A 30-year-old woman underwent a long-treatment protocol for ovarian stimulation. Fourteen mature oocytes were obtained, and twelve were fertilized.

Perinatal outcomes following transfer of human blastocysts vitrified at day 5, 6 and 7.

Little information is available on perinatal outcome of cryopreserved day-7 blastocyst transfer. In the present report, perinatal outcomes for transfers of cryopreserved blastocysts by a vitrification method were examined with respect to the day of blastocyst expansion among on day 5, 6 or 7 before cryopreservation. We investigated 263 cycles of vitrified-warmed blastocyst stage embryo transfer performed between April 2005 and April 2009, which were reviewed retrospectively.

Vitrified human day-7 blastocyst transfer: 11 cases.

This case report describes successful pregnancies after vitrification of human day-7 blastocysts. A total of 16 day-7 blastocysts were vitrified and warmed. All 16 blastocysts survived after warming and were transferred to 11 patients.

Case report: two successful pregnancies following the transfer of re-vitrified human day 7 blastocysts developed from vitrified cleaved embryos.

Purpose: To report successful pregnancies after the transfer of re-vitrified human day 7 blastocysts developed from vitrified cleaved embryos.

Methods And Results: A total of five day 7 blastocysts developed from vitrified cleaved embryos were re-vitrified and re-warmed. All of five re-vitrified day 7 blastocysts (100%) survived after warming and were transferred to three patients.

Effect of the size of zona pellucida opening by laser assisted hatching on clinical outcome of frozen cleaved embryos that were cultured to blastocyst after thawing in women with multiple implantation failures of embryo transfer: a retrospective study.

Purpose: To evaluate the effect of the size of zona pellucida opening by laser assisted hatching for frozen cleaved embryo that were thawed after both fresh and frozen cleaved embryo transfer cycles failed and were cultured to blastocyst after thawing in patients with multiple implantation failures.

Materials And Methods: Of 101 consecutive procedures (October 2003 to June 2006), 30 patients declined to perform assisted hatching and were selected as control group, 40 patients had 40 microm opening of the zona (October 2003 to January 2005), 31 patients had 50% of the zona opening (February 2005 to June 2006).

Results: The pregnancy, implantation and delivery rates were significantly higher in 50% opening group (74%, 52% and 65%) compared to control group (17%, 10% and 13%; P < 0.

Zona pellucida removal and vitrified blastocyst transfer outcome: a preliminary study.

The objective of this study was to investigate whether a change in assisted hatching technique from partial opening to total removal of the zona pellucida improved the outcome of vitrified blastocyst transfer. This was a preliminary observational study conducted from November 2003 to April 2006. Partial opening using acid Tyrode's solution was performed in 45 cycles, while total removal using a laser and mechanical pipetting was performed in 57 cycles.

Vitrification of human hatched blastocysts: a report of 4 cases.

Background: Vitrification is a fairly well-established technique for cryopreservation of human zona-intact blastocysts. However, little is known about the efficacy of the vitrification technique for zona-free hatched blastocysts.

Case: A total of 4 hatched blastocysts from 4 healthy, infertile women undergoing in vitro fertilization were vitrified and warmed.

Successful dizygotic twin pregnancy after recryopreservation by vitrification of human expanded blastocysts developed from frozen cleaved embryos on day 6: a case report.

Background: Vitrification has evolved into an established technique for cryopreservation of human blastocysts. However, it is still unclear whether the blastocysts developed from frozen embryos can be cryopreserved a second time by vitrification for further embryo transfer.

Case: A 31-year-old woman underwent a long-treatment protocol for ovarian stimulation.

Blastocoele collapse by micropipetting prior to vitrification gives excellent survival and pregnancy outcomes for human day 5 and 6 expanded blastocysts.

Background: Manual puncture of the trophectoderm of human blastocysts with a needle before vitrification increases their survival rate, but the embryos take a long time to re-expand. This study examined whether causing human blastocysts to collapse by manual pipetting before vitrification would allow more rapid re-expansion and improve pregnancy rates.

Methods: After embryo transfer in IVF cycles, surplus embryos that developed to the expanded blastocyst stage were placed in cryoprotectant and then artificially shrunk by mechanical pipetting with a fine hand-drawn glass pipette slightly smaller in diameter than the blastocyst.

Case report: successful pregnancy after vitrification of a human blastocyst that had completely escaped from the zona pellucida on day 6.

This case report describes a successful pregnancy after vitrification of a human hatched blastocyst. A 31-year-old woman, after failed stimulated and thaw cycles, underwent short-treatment protocol stimulation, and oocytes were recovered transvaginally with ultrasound guidance. Eight mature oocytes were obtained and six were fertilized with conventional IVF.