Quality standard
Quality statement 8: Number of embryos transferred
Quality statement 8: Number of embryos transferred
Quality statement
Women having in vitro fertilisation (IVF) have 1 or 2 embryos transferred according to the woman's or donor's age, the cycle number and the quality of the embryos.
Rationale
An effective embryo transfer strategy minimises the chance of multiple pregnancies following IVF and improves the outcome of IVF with the birth of more single, healthy babies. Multiple pregnancies represent a significant health risk to mothers and babies.
Quality measures
Structure
Evidence of local arrangements to implement an agreed embryo transfer strategy in which 1 or 2 embryos are transferred according to the woman's or donor's age, the cycle number and the quality of the embryos.
Data source: Local data collection.
Process
a) Proportion of IVF cycles in which embryo transfers are carried out in line with NICE's guideline on fertility problems (see also the definitions section below).
Numerator – the number in the denominator carried out in line with NICE's guideline on fertility problems.
Denominator – the number of embryo transfers in IVF cycles.
Data source: Local data collection.
Outcome
a) Proportion of embryo transfers that are elective single embryo transfers.
Data source: Local data collection. National data on elective single embryo transfers are available from the Human Fertilisation and Embryology Authority.
b) Number of IVF treatments resulting in multiple pregnancy.
Data source: Local data collection. National data on multiple pregnancy rates following IVF treatment are available from the Human Fertilisation and Embryology Authority.
What the quality statement means for different audiences
Service providers (specialist fertility services) ensure that systems are in place to monitor the number of embryos transferred during IVF cycles.
Healthcare professionals (in specialist fertility services) transfer the appropriate number of embryos during IVF, taking into account the woman's or donor's age, the cycle number and the quality of the embryos.
Commissioners (clinical commissioning groups) ensure that the services they commission have policies in place on embryo transfer strategies that take into account the woman's or donor's age, the cycle number and the quality of the embryos.
Women having IVF have 1 or 2 embryos transferred into their womb, depending on the woman's age (or the donor's age), the number of IVF treatments she has had and the quality of the embryos.
Source guidance
Fertility problems: assessment and treatment. NICE guideline CG156 (2013), recommendations 1.12.6.5, 1.12.6.8 (key priorities for implementation), 1.12.6.6 and 1.12.6.7
Definitions of terms used in this quality statement
The number of embryos transferred should be determined by the age of the woman, cycle number and quality of embryos as follows.
|
Age |
Cycle |
Quality of embryos (evaluated at both cleavage and blastocyst stages) |
Number of embryos to transfer |
|---|---|---|---|
|
Under 37 |
1st |
N/A |
1 |
|
Under 37 |
2nd |
1 or more top‑quality embryos available |
1 |
|
Under 37 |
2nd |
If no top‑quality embryos are available |
No more than 2 |
|
Under 37 |
3rd |
N/A |
No more than 2 |
|
37 to 39 |
1st or 2nd |
1 or more top‑quality embryos available |
1 |
|
37 to 39 |
1st or 2nd |
If no top‑quality embryos are available |
No more than 2 |
|
37 to 39 |
3rd |
N/A |
No more than 2 |
|
40 to 42 |
N/A |
N/A |
No more than 2 |
|
N/A |
N/A |
Top‑quality blastocyst available |
1 |
Embryo quality is evaluated at both cleavage and blastocyst stages, according to the Association of Clinical Embryologists (ACE) and UK National External Quality Assessment Service (UK NEQAS) for Reproductive Science Embryo and Blastocyst Grading schematic.
[Adapted from NICE's guideline on fertility problems]