The National Institute for Health and Clinical Excellence (NICE) is considering tightening its guidelines on embryo implantation with the possibility that, in future, only single embryo transfers (SET) may be recommended.
In updating its official guidance to clinicians, last examined in 2004, NICE will also consider new research and evidence on the optimal timing of embryo transfers, the effectiveness of intrauterine insemination, the relative strengths of 'mild' versus regular IVF, sperm washing and tests for assessing ovarine reserves.
The current guidance on embryo transfer states: 'To balance the chance of a live birth and the risk of multiple pregnancy and its consequences, no more than two embryos should be transferred during any one cycle of IVF treatment'. However, it also appears to endorse SET in principle by identifying a need for: 'further research to improve embryo selection to facilitate single embryo transfers'.
Over a quarter of IVF babies in the UK are from a multiple birth, which carries associated health risks. Risks for the children include higher fetal mortality, greater risk of premature birth, lower average birth weight and higher rates of disability. Mothers face a greater risk of complications during pregnancy and, in particular, pre-eclampsia. Critics say SET may reduce the chances of conceiving, thereby increasing the number of cycles required and the overall cost of treatment.
It is hoped savings from reduced multiple births may justify the extra cost of additional cycles. Susan Seenan, spokesperson for Infertility Network UK (who is collaborating with NICE on the update) said: 'We are supportive of SET for the right women, but it has got to come with full NHS funding'. Tony Rutherford, chair of the British Fertility Society, said studies identifying decreased neonatal illness clearly validated SET policies.
The new guidance is expected to be published no sooner than 2012. The current guidelines remain in place until then.