Cost-effectiveness analysis of different embryo
transfer strategies in England
S Dixon,a F Faghih Nasiri,b WL Ledger,c EA Lenton,d A Duenas,a P Sutcliffe,a JB Chilcotta
a Health Economics and Decision Science, School of Health and Related Research, University of Sheffield, Sheffield, UK bManagement School,
University of Lancaster, Lancaster, UK c Academic Unit of Reproductive and Developmental Medicine, University of Sheffield, Sheffield, UK
d Independent Fertility Consultant, Sheffield, UK
Correspondence: Dr S Dixon, Health Economics and Decision Science, School of Health and Related Research, University of Sheffield, Regent Court,
30 Regent Street, Sheffield S1 4DA, UK. Email s.dixon@sheffield.ac.uk
Accepted 28 December 2007. Published OnlineEarly 19 March 2008.
Objective The objective of this study was to assess the cost-
effectiveness of different embryo transfer strategies for a single
cycle when two embryos are available, and taking the NHS cost
perspective.
Design Cost-effectiveness model.
Setting Five in vitro fertilisation (IVF) centres in England between
2003/04 and 2004/05.
Population Women with two embryos available for transfer in
three age groups (<30, 30–35 and 36–39 years).
Methods A decision analytic model was constructed using
observational data collected from a sample of fertility centres in
England. Costs and adverse outcomes are estimated up to 5 years
after the birth. Incremental cost per live birth was calculated for
different embryo transfer strategies and for three separate age
groups: less than 30, 30–35 and 36–39 years.
Main outcome measures Premature birth, neonatal intensive care
unit admissions and days, cerebral palsy and incremental cost-
effectiveness ratios.
Results Single fresh embryo transfer (SET) plus frozen single
embryo transfer (fzSET) is the more costly in terms of IVF costs,
but the lower rates of multiple births mean that in terms of total
costs, it is less costly than double embryo transfer (DET). Adverse
events increase when moving from SET to SET+fzSET to DET. The
probability of SET+fzSET being cost-effective decreases with age.
When SET is included in the analysis, SET+fzSET no longer
becomes a cost-effective option at any threshold value for all age
groups studied.
Conclusions The analyses show that the choice of embryo transfer
strategy is a function of four factors: the age of the mother, the
relevance of the SET option, the value placed on a live birth and
the relative importance placed on adverse outcomes. For each
patient group, the choice of strategy is a trade-off between the
value placed on a live birth and cost.
Keywords Cost-effectiveness analysis, decision analytic
modelling, embryo transfer, in vitro fertilisation, paediatric
outcomes.
Please cite this paper as: Dixon S, Faghih Nasiri F, Ledger W, Lenton E, Duenas A, Sutcliffe P, Chilcott J. Cost-effectiveness analysis of different embryo transfer
strategies in England. BJOG 2008;115:758–766.
Introduction
The chances of pregnancy and live birth following in vitro
fertilisation (IVF) have risen steadily over the past two deca-
des. IVF accounts for over 1:100 births in many European
countries and 1.4% of births in the UK.1 Together with the
undoubted benefits of assisted reproductive technologies in
helping infertile couples to have families, there are several
negative consequences, the most important being the large
increase in the number of multiple births seen after IVF.
Although there has been a fall in triplet pregnancies since
1998, the number of twin births in UK resulting from assisted
reproductive technologies continues to rise.2 The perinatal
morbidity and mortality of twin pregnancy was reviewed by
a Human Fertility and Embryology Authority Expert Group
on Single Embryo Transfer in 2006.3 The expert group has
advised that UK policymakers consider a move towards
increasing use of single embryo transfer in IVF to reduce
the unacceptable morbidities that follow twinning.
The Northern European countries in which ‘single embryo
transfer policies’ have most successfully been introduced are
also those which have a more generous amount of State sup-
port for assisted reproductive technologies than is currently
seen in UK. Although the National Institute for Clinical
758 ª 2008 The Authors Journal compilation ª RCOG 2008 BJOG An International Journal of Obstetrics and Gynaecology
DOI: 10.1111/j.1471-0528.2008.01667.x
www.blackwellpublishing.com/bjog
Fertility and assisted reproduction

Excellence (NICE) guidelines on management of subfertility
recommended provision of three full cycles of IVF to women
less than 40 years who require this treatment, little progress
has been made in implementing this guidance.4 One recent
survey has shown that of those Primary Care Trusts (PCTs)
that offer any treatment at all, most offer one cycle and only
9% offer two cycles of IVF.5
One means by which UK Primary Care Trusts might be
encouraged to provide the services offered to the nation by
the Minister for Health in 2004 would be to make explicit the
cost and outcomes associated with different embryo transfer
strategies. A number of studies have attempted to assess the
cost of multiple births to the NHS by modelling the obstetric
and postnatal costs of complications of multiparity.6,7 How-
ever, economic evaluations of single embryo transfer under-
taken to date, with one exception,8 have omitted maternal and
paediatric adverse events.9–13
Estimating the cost-effectiveness of different strategies,
including the costs of adverse events, would help commis-
sioners plan for the consequences of meeting the NICE tar-
gets, in terms of costs, birth rates and adverse event rates. As
part of a regional initiative—the Evidence-Based Commis-
sioning Collaboration—we devised a decision analytic mod-
elling approach to evaluate this problem in terms of antenatal,
maternal, neonatal and paediatric costs, birth rates and
adverse event rates. The approach also allowed us to assess
how the optimal strategy changes with maternal age, the avail-
ability of embryo storage and the number of embryos avail-
able (although this final issue is not addressed in this paper).
This study, therefore, assesses the cost-effectiveness of differ-
ent embryo transfer strategies for a single cycle when two
embryos are available and takes the NHS cost perspective.
Methods
There are two main aspects to consider when an IVF treat-
ment is applied: (a) the effectiveness of the embryo trans-
fer(s) and (b) the costs/outcomes related to the resultant
birth outcomes. These are shown schematically in Figure 1.
The model defines the outcomes as: no transfer, no live
birth, singleton live birth, twin live birth or triplet or higher
multiple live birth. When summarising cost-effectiveness in
an incremental cost per live birth, live birth means any type
of birth (i.e. singleton, twin and triplet all receive the same
weighting).
This model was used to investigate costs and outcomes
associated with different embryo transfer strategies for a vary-
ing number of embryos. A strategy was defined as a combina-
tion of single/double, fresh/frozen embryo transfer within a
cycle.14 The strategy was based on the number of available
embryos at the beginning of the cycle. In this paper, we
evaluate the situation where two embryos are available. The
main comparison is between the transfer of two fresh emb-
ryos, which is referred to as double embryo transfer (DET),
and single fresh embryo transfer (SET), which if unsucces-
sful leads to the transfer of a previously frozen single embryo
transfer (fzSET).
Antenatal, maternal, neonatal and paediatric costs together
with adverse outcomes are all based on the type of live birth,
defined as being singleton, twin or triplet and higher. The
individual components of costs were not modelled here as
previous work was used to define a quantum of cost associ-
ated with each birth outcome (see ‘Data’). These costs were
assessed up to 5 years after delivery. The adverse outcomes
were specified through consultation with commissioners
*Or higher order multiple births.
**Up to age 5.
Fresh
cycle
No
transfer
No
live birth
Singleton
live birth
Twin live
birth
Triplet*
live birth
Premature delivery
Cerebral palsy
NICU admission
Birth
Neonatal care
Paediatric care**
Frozen cycle (if
available)
Pathway same
as fresh cycle
As per
twin
As per
twin
}
}
}
}
}
}
}
After treatment
costs
Adverse outcomes
Antenatal care
Figure 1. Model structure.
Cost-effectiveness strategies of different embryo transfer
ª 2008 The Authors Journal compilation ª RCOG 2008 BJOG An International Journal of Obstetrics and Gynaecology 759