Subscribe to the BioNews newsletter for free

Login
Advanced Search

Search for
BioNews

Like the Progress Educational Trust on Facebook


The Fertility Show


 

Correction: Slow-frozen embryos seem to produce healthier babies in IVF

24 November 2008

By BioNews

Appeared in BioNews 485

In BioNews 484, we published a story reporting on new evidence to suggest that in IVF 'vitrified' embryos may be better than 'fresh' embryos. It has been brought to our attention that the technique used to store embryos in these studies was in fact 'slow-freezing', or 'controlled-rate freezing', and not vitrification as reported.

Controlled-rate freezing avoids the formation of potentially damaging ice crystals by allowing time for the concentration of solutes in the embryo to reach equilibrium in a cryoprotectant (a form of anti-freeze), before cooling in a predetermined, controlled way. Vitrification also aims to avoid the formation of ice crystals in the embryo, but does so by boosting the levels of cryoprotectant in order to avoid freezing and produce a glassy or 'vitreous' state at very low temperature.

While controlled rate freezing has been used in embryo storage since the 1980's, resulting in hundreds of thousands of healthy births, vitrification is, by comparison, a relatively new technology, which has so far only been attempted in a relatively small number of births. It would therefore have been impossible to achieve the large sample sizes recorded in these studies if not using the significantly more established slow-freezing technique.

SOURCES & REFERENCES

RELATED ARTICLES FROM THE BIONEWS ARCHIVE

17 November 2008 - by Alison Cranage 
Three new independent studies have provided further evidence that embryos stored using slow-freezing techniques may be better than fresh for IVF. The studies were presented at the American Society for Reproductive Medicine conference in San Francisco, US, last week. The studies indicate that using frozen embryos rather...

HAVE YOUR SAY
Be the first to have your say.

You need to or  to add comments.

By posting a comment you agree to abide by the BioNews terms and conditions


- click here to enquire about using this story.

Published by the Progress Educational Trust

CROSSING FRONTIERS

Moving the Boundaries of Human Reproduction

Public Conference
London
8 December 2017

Speakers include

Professor Azim Surani

Professor Magdalena Zernicka-Goetz

Professor Robin Lovell-Badge

Sally Cheshire

Professor Guido Pennings

Katherine Littler

Professor Allan Pacey

Dr Sue Avery

Professor Richard Anderson

Dr Elizabeth Garner

Dr Jacques Cohen

Dr Anna Smajdor

Dr Andy Greenfield

Vivienne Parry

Dr Helen O'Neill

Dr César Palacios-González

Philippa Taylor

Fiona Fox

Sarah Norcross


BOOK HERE

Good Fundraising Code

Become a Friend of PET HERE and give the Progress Educational Trust a regular donation