Frozen embryos are more likely to produce successful, complication-free IVF pregnancies than those that are fresh, research suggests.
Using stored embryos cuts the risk of bleeding in pregnancy, premature birth, and giving birth to an underweight baby by almost a third, a study has found.
The risk of a baby dying at around the time of birth is also reduced by about a fifth.
If the findings are confirmed it could have major implications for the public funding of In-Vitro Fertilisation treatment.
Currently the NHS regards embryo freezing as an extra service patients are expected to pay for themselves.
If freezing becomes a routine part of IVF treatment there may be pressure to change this rule.
Scientists made the discovery after analysing data from 11 international studies involving more than 37,000 IVF pregnancies.
In some cases, newly conceived fresh embryos were used. In others, embryos that had been frozen and stored for two to three months were implanted.
Standard practice is to choose the best embryos for fresh transfer, and only freeze those of good enough quality that are spare.
But the new results suggest it might be wise to freeze all embryos.
Daybreak's Health Editor Dr Hilary Jones explains:
– Dr Abha Maheshwari, senior lecturer at the University of Aberdeen
The existing data do have a number of limitations which need to be addressed in the context of further research before this strategy should be rolled out into routine clinical practice.
The initial step must be to provide robust evidence to demonstrate that elective freezing of embryos can increase the chances of having a healthy baby, which would be best performed in the context of a large randomised controlled trial.
In the meantime my advice to women undergoing IVF is that there is no reason, yet, to change the way they approach IVF.
What is embryo freezing and storage?
- During in vitro fertilisation (IVF) or intra-cytoplasmic sperm injection (ICSI) treatment, fertility drugs are used to stimulate the ovaries to produce more eggs than usual.
- These are then fertilised with your partner’s, or a donor’s sperm to create embryos.
- Because there is normally a number of unused embryos, some people choose to freeze the good quality unused embryos for use in later treatment cycles or for donation.