Page last updated at 23:06 GMT, Tuesday, 2 September 2008 00:06 UK

Single embryo guidance to clinics

Clinical Embryologist Rachel Cutting on the potential advantages

Fertility clinics are to receive guidance aimed at cutting the rate of multiple pregnancies.

The British Fertility Society and Association of Clinical Embryologists recommends transferring only one embryo per IVF cycle wherever possible.

Multiple pregnancies pose a higher health risk to both mother and baby.

The Human Fertilisation and Embryology Authority (HFEA) has asked clinics to cut the multiple pregnancy rate from an average 24% to 10% in three years.

Transferring only one embryo to those women most at risk of having twins is the only effective method to reduce the multiple birth rate after IVF treatment
Tony Rutherford
British Fertility Society

Currently, many clinics opt to transfer two embryos into a patient's womb during IVF treatment to maximise the chance of a successful pregnancy.

But this raises the risk of a multiple pregnancy, which is associated with a raised risk of miscarriage, stillbirth, premature birth, low birth weight and long-term developmental problems.

Mothers also have a raised risk of the potentially life-threatening pregnancy condition pre-eclampsia, diabetes and heart disease.

The new guidelines, published in the journal Human Fertility, give advice on how clinics can adopt a single embryo transfer policy, including careful assessment of patients' suitability.

In the UK, most multiple IVF pregnancies occur in women under the age of 37.

It is this group which the guidelines suggest is suitable for single embryo transfer, provided spare high quality embryos are available to be frozen for possible later use.

Freezing spare embryos avoids the need for women to undergo further costly cycles of ovary stimulation to harvest more eggs.

Clinics are also urged to provide more "mild" IVF cycles which involve collecting fewer eggs and creating fewer embryos.

Three mild cycles are said to be as effective as two more vigorous cycles while resulting in fewer complications.

Funding required

Tony Rutherford, chairman of the BFS Policy and Practice Committee, said the success of the new strategy was dependent on more NHS funding.

He said: "Transferring only one embryo to those women most at risk of having twins is the only effective method to reduce the multiple birth rate after IVF treatment.

"It is imperative that elective single embryo transfer is made the norm for these women in the UK, as it is elsewhere in Europe."

The National Institute for Health and Clinical Excellence (NICE) recommends patients should be entitled to up to three free IVF cycles on the NHS.

However, there is evidence that this is denied to many patients, and that freezing of spare embryos is often not included in NHS-funded treatment.

Claire Brown, of the IVF patient charity Infertility Network, said this was "totally unacceptable, if not unethical".

Alan Doran, HFEA interim chief executive, said multiple pregnancy was the single biggest risk of fertility treatment, and said the case for action to cut rates was "overwhelming".

However, he stressed that nobody was suggesting a "one size fits all" approach to fertility treatment.

'One egg' IVF strategy launched
26 Jun 08 |  Health

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