Transferring single embryos to women's wombs over several assisted reproduction cycles that use both fresh and frozen embryos is more effective and cheaper than transferring two or more embryos at one time, according to data from the world's longest running series of patients who choose to have only one embryo implanted per cycle - elective single embryo transfer (eSET).
The authors of the Finnish study published online today (Wednesday 25 March) in Europe's leading reproductive medicine journal Human Reproduction, say that their results effectively refute any concerns there have been up to now about the cost implications of an eSET policy and any fears that it could result in a lower rate of live births. In addition, it halves the rates of multiple pregnancies - the cause of potential medical complications and death for both babies and mothers.
Dr Hannu Martikainen, Chief Physician of the Division of Infertility and Reproductive Endocrinology at the University of Oulu, Finland, said: "This is the first study to evaluate the cumulative effect of fresh cycles with subsequent cycles using frozen-thawed embryos in a complete, consecutive (and therefore unselected) patient population over an extended period of time. Our study, thus, reflects eSET in everyday practice with an outcome measure consistent with what patients actually want: a live healthy baby achieved in a cost-effective way.
"We found that a baby born alive at term using eSET was, on average, 19,889 euros less expensive than babies born as a result of double embryo transfer."
The researchers, led by Dr Martikainen, compared the outcomes of IVF/ICSI cycles in two periods at their fertility clinic: 1995-1999 when eSET was rarely used (4.2% of women), and double embryo transfer (DET) was much more common (called the "DET period" for the purposes of this study), and 2000-2004 when eSET was used more widely (46.2% of women) - the eSET period.
Over the ten-year period, 1,510 women younger than 40 were treated at the infertility unit at Oulu University Hospital. They had a total of 2,386 cycles when fresh embryos were transferred, followed by 1,272 cycles when frozen-thawed embryos were transferred (FET). About 90% of deliveries in both periods occurred within the first four treatment cycles, suggesting that the time to delivery with eSET is no longer than that for DET.
The researchers found there was a significant difference between the DET and eSET periods in terms of effectiveness and cost. The cumulative pregnancy rate and cumulative live birth rate per egg retrieval ("ovum pick-up") and the cumulative live birth rate per woman were all higher in the eSET period. Cumulative pregnancy rate per ovum pickup was 38.2% (eSET) versus 33.1% (DET), cumulative live birth rate per ovum pickup was 28% versus 22.5%, and cumulative live birth rate per woman was 41.7% versus 36.6%. In addition, the cumulative multiple birth rate was significantly lower in the eSET period (8.9% versus 19.6% in the DET period).
Dr Zdravka Veleva, from the same team, who is responsible for the economic analysis of the study, showed that the total treatment cost per woman in the eSET period was, on average, five per cent less than in the DET period (ranging from 2-20% less). In terms of euros, the total treatment cost per woman decreased by an average of 275 euros (ranging between 164-1184 euros) from the DET to the eSET period. When the researchers calculated the incremental cost-effectiveness ratio (ICER) [2] they found that 19,889 euros was saved per live baby born at term (after 37 weeks) in the eSET period compared with the DET period.
Dr Martikainen said: "There are few IVF centres in the world with greater experience than ours of eSET over such a long period of time. This study shows that the implementation of an eSET policy, together with an effective embryo freezing programme, results in a better outcome and lower treatment cost for women under the age of 40 having in vitro fertilisation, intra-cytoplasmic sperm injection (ICSI) or both. This refutes any concerns about the cost implications or efficacy of an eSET policy.
"At a time when there is an intense debate in many countries about how to reduce multiple pregnancy rates and provide affordable fertility treatment, policy makers should be made aware of our results. Hopefully this will encourage them to improve the reimbursement of assisted reproduction treatment, especially as it shows that a limit of only one reimbursed cycle will not necessarily result in lower costs once you take into account the far higher social and financial costs of treating the complications caused by multiple births arising from dual or multiple embryo transfer.
"These data should also encourage clinics to evaluate their embryo transfer policy and adopt eSET as their everyday practice for women younger than 40."