Pregnancy rates following the exclusive transfer of twice frozen twice thawed embryos using a modified slow cool cryopreservation technique.

Purpose: To determine the pregnancy rate following the exclusive transfer of twice frozen twice thawed embryos.

Materials And Methods: All day 3 transfers of exclusive twice frozen-twice thawed embryos were retrospectively identified over a 13-year time-period. The cryopreservation technique used a simplified slow cool freezing protocol.

Oocytes from women of advanced reproductive age do not appear to have an increased risk of zona pellucida hardening.

Purpose: To test the hypothesis that very advanced reproductive age leads to an increased risk of zona pellucida hardening by comparing fertilization rates and rates of failed fertilization with conventional oocyte insemination vs intracytoplasmic sperm injection (ICSI).

Methods: Women aged > or = 45 were given the option of ICSI vs conventional oocyte insemination in circumstances where there was no male factor present. They were advised of the theoretical benefit of ICSI overcoming zona hardening but also advised that ICSI might lower pregnancy rates and is more costly.

Effect of method of oocyte fertilization on fertilization, pregnancy and implantation rates in women with unexplained infertility.

Purpose: To determine if intracytoplasmic sperm injection (ICSI) offers an advantage over conventional oocyte insemination for women undergoing in vitro fertilization (IVF) and embryo transfer for unexplained infertility.

Methods: A retrospective seven-year review of outcome following IVF with conventional insemination vs ICSI for the category of unexplained infertility. The decision on which method of insemination to use was made by the couple after hearing pros and cons with the consulting physician.