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 Fertility (NICE guideline CG156) (see also the definitions section below).

Numerator – the number in the denominator carried out in line with Fertility (NICE guideline CG156).

Denominator – the number of embryo transfers in IVF cycles.

Data source: Local data collection. Data can be collected using the NICE clinical audit tool for fertility: embryo transfer strategies: audit standards 4–7.

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 service providers, healthcare professionals and commissioners

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.

What the quality statement means for patients

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 (2013) NICE guideline CG156, 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

Embryo transfer according to age, cycle number and quality of embryos

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 1

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

37–39

1st or 2nd

1 or more top‑quality embryos available

1

37–39

1st or 2nd

If no top‑quality embryos are available

No more than 2

37–39

3rd

N/A

No more than 2

40–42

N/A

N/A

No more than 2

N/A

N/A

Top‑quality blastocyst available

1

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 Fertility (NICE guideline CG156)]

Equality and diversity considerations

The existence of living children should not be a factor that precludes the provision of fertility treatment.