Often, infertility patients wonder whether the technology will affect the outcome of their babies. We have been reassured by several reports regarding the obstetrical outcomes and risk of birth defects with human oocyte cryopreservation.

Chian et al.(2008) reported on the obstetrical outcomes of over 200 babies resulting from oocyte vitrification in three centers, comparing them to spontaneously conceived, or ART conceived neonates. Mean birth weights and rate of anomalies was similar

Noyes et al. published a meta-analysis of more than 600 babies born from oocyte cryopreservation, almost half from vitrification, which showed a 1.3% rate of birth defects, well within the expected rate for naturally conceived babies.

Forman et al. (2012) found no increase in embryonic chromosomal errors when vitrified ova were compared to non-vitrified ova. These investigators utilized cycles of 44 patients with a mean age of about 30 years, utilizing 588 mature oocytes. Fertilization rates using ICSI and blastocyst development rates were lower with vitrification. However, pregnancy rates were similar when blastocysts were transferred (54% vs. 58%).

Recently, Goldman et al (2015) using age-matched controls, demonstrated that although blastulation (development to blastocyst) rates of vitrified ova were lower than with fresh ova (54.5% vs 66.2%), they had equivalent rates of euploidy, implantation and live birth when compared to blastocysts derived from fresh oocytes. In this study, all embryos were biopsied and underwent Preimplantation Genetic Screening (array Comparative Genome Hybridization).

Although further study is warranted, it seems that we can reassure patients that there is no increased risk associated with oocyte vitrification.

Dr. Patricia McShane has been involved in reproductive medicine since the early days of IVF in the US. She has been the medical director for a large private fertility center as well as taught and practiced in academic medicine. She was very gratified when egg freezing became a practical clinical reality. Dr. McShane is the medical director of The World Egg Bank.

Dr. Kimball O. Pomeroy is the Science Director for The World Egg Bank. He has directed several clinical laboratories throughout the US. He was trained in Bristol, England as a human embryologist and prior to that was educated at Colorado State University, receiving a PhD in Animal Physiology, and then worked at the Salk Institute for Biological Studies, where he did post-doctoral work in molecular biology. At the Salk Institute, Dr. Pomeroy was a molecular biologist and worked with Dr. Glen Evans on the Human Genome Project (chromosome 7) and did work in transgenics.

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RC Chian et al. Obstetrical and perinatal outcome in 200 infants conceived from vitrified oocytes. Reproductive BioMedicine Online 16:608-610, 2008

N Noyes, E Porcu, A Borini. Over 900 oocyte cryopreservation babies born with no apparent increase in congenital anomalies. Reproductive BioMedicine Online 18:769-776, 2009

E Forman et al. Oocyte vitrification did not increase the risk of embryonic aneuploidy or diminish the implantation potential of blastocysts created after intracytoplasmic sperm injection: a novel, paired randomized controlled trial using DNA fingerprinting. Fertil Steril 98:644-649, 2012

K Goldman et al. Long-term cryopreservation of human oocytes does not increase embryonic aneuploidy. Fertil. Steril.103:662-668, 2015

Dr. Patricia McShane has been involved in reproductive medicine since the early days of IVF in the US. She has been the medical director for a large private fertility center as well as taught and practiced in academic medicine. She was very gratified when egg freezing became a practical clinical reality. Dr. McShane is the medical director of The World Egg Bank.