16-09-13 Progress in reducing multiple birth rates

The Human Fertilisation and Embryology Authority recently reviewed the sector’s progress in reducing multiple birth rates. Fertility clinics have worked hard over the past few years to implement their multiple births minimisation strategy and have risen to this public health challenge.  A maximum multiple live birth rate of 10% has been in place since October 2012, which is the rate the HFEA has been aiming for from the outset of the policy. Clinics have been reviewing and auditing their multiple births minimisation strategies to try to meet this rate.

Since the HFEA first implemented a multiple births policy in 2009 clinics have reduced the multiple live birth rate from around 24% to around 17% in 2012. The proportion of transfers that are elective single embryo transfers (eSET) has increased from about 5% to currently about 25%. The proportion of blastocyst transfers has increased dramatically, from about 13% to currently about 47% – the majority (about two thirds) of eSETs are blastocyst transfers.

Making decisions about the number of embryos to transfer can be difficult, but the experience so far is reassuring. Many patients are concerned that transferring just one embryo will reduce their chances of success. This is not the case: as you can see from the following table there is little difference between the pregnancy rate after fresh elective single embryo transfer or double embryo transfer, for all age groups. 

Overall pregnancy rates (per embryo transfer) and multiple pregnancy rates (from April 2011 – October 2012)

Patient age  eSET preg. rate  eSET multiple preg. rate DET preg. rate   DET multiple preg. rate
Under 35  42.0  1.7  39  35.2
35 - 37  37.6  1.6  35.4  28.9
38 - 39  34.4  <1  30.6  24.7
All ages  39.6  1.5  34.0  30.20

An ongoing patient survey indicates that almost half of patients are recommended single embryo transfer. Just over half of these patients then go on to have single embryo transfer, mainly because the clinic recommended it, patients trusted their clinic’s opinion and were concerned about the risks of multiple pregnancies.

More detailed data, regarding the sector’s progress, can be found in a recent Human Fertilisation and Embryology Authority report (‘Multiple births update’ paper).

We are really pleased with how the sector has responded to the challenge to reduce multiple birth rates.