Multiple pregnancy is the single biggest risk to the health and welfare of patients and children born from fertility treatment. It can lead to both short and long-term health problems, and places a financial burden on the health service.
Transferring one embryo in patients most at risk of conceiving a multiple pregnancy will give children born from IVF the best possible start in life, by reducing their chances of being born as a twin.
NHS commissioners play a vital role in supporting the use of single embryo transfer (SET) in clinics. Providing funding for three full cycles of IVF, including follow-on frozen embryo transfers, makes a real difference in encouraging patients to have SET.
In addition, eligibility criteria that recognise the balance between minimising the risk of multiple pregnancy whilst not compromising patients’ chances of having a baby, can help clinics provide the most appropriate care for their patients.
Currently, nearly 1 in 4 IVF births result in a multiple birth; twenty times higher than if a woman conceives naturally. This has resulted in an increase in the national twinning rate and presents a significant public health concern.
Multiple pregnancy is the most serious risk that IVF children face. Many of the health risks for twins are due to the higher likelihood of them being born prematurely. Perinatal mortality, neonatal morbidity, and long-term health implications are all higher for twins. Multiple pregnancy also has increased health risks for mothers.
The neonatal and paediatric care that premature children require has a large impact on the NHS. A recent study estimated that, in England and Wales:
The cost relates to a hypothetical cohort of 669,601 children over the first 18 years of life. It encompasses the cost of health, social and education services and is based on 2006 prices.Read more about the risks to children and mothers from multiple pregnancy…
Patients who are most likely to get pregnant following IVF are also most at risk of conceiving a multiple pregnancy. These are the patients who benefit from single embryo transfer (SET).
Clinics should assess whether a patient is eligible for SET based on criteria such as their age and quality of their embryos. Typical criteria may be women under 37, who produce at least one good quality embryo and are on their first or second IVF attempt.
SET is not clinically effective, and therefore not cost effective, for all patients. Patients who are less likely to conceive, for example older women with poor quality embryos or those who have had repeated unsuccessful IVF attempts, are also unlikely to be at risk of a multiple pregnancy. Therefore those patients would not benefit from SET and it may compromise their chances of becoming pregnant at all.
NHS funding policies should allow clinics discretion to be able assess whether SET is appropriate for individual patients.
It is a common concern that SET may compromise patients’ chances of becoming pregnant. However clinics can maintain their overall success rates by:
Clinics around the UK are now starting to demonstrate that they are able to lower their multiple pregnancy rate without reducing their overall pregnancy rate through careful patient selection for SET.
Published studies and evidence from other countries show that patients can have as good as, or better, chance of success from SET compared to transferring two embryos, when the success rates from a single fresh embryo transfer are combined with any follow-on treatment using frozen embryo transfers. Importantly SET will also virtually eliminate the risk of having a multiple birth.
Frozen embryo transfers are far less invasive and safer for the patient than an additional fresh cycle, as the patient will not need to go through stimulation to retrieve more eggs.
It is therefore vital for funding criteria to support SET in only those patients who are most at risk of multiple pregnancy, without issuing a ‘one-size-fits-all’ approach, and to provide follow-on frozen embryo transfers.
The Human Fertilisation and Embryology Authority (HFEA) introduced a policy in 2009 to reduce the multiple birth rate in clinics from its current rate of 24% to 10%, over a number of years. Each year the HFEA sets a maximum multiple birth rate that clinics must not exceed. Clinics are required to have a strategy setting out how they will achieve this in their clinic.
For treatment started in 2009 the HFEA stated that no more than 24% of a clinic’s total live births should be multiple births. In April 2010 this was lowered to 20% multiple births. This will be lowered again in April 2011.
All IVF clinics must have a ‘Multiple births minimisation strategy’ that sets out how they will reduce multiple births from IVF treatment. It must include patient selection and embryo assessment criteria for how the clinic will identify patients for whom SET is suitable. Clinics are required to regularly audit and evaluate the effectiveness of their strategy.
The HFEA regularly monitors clinics’ multiple pregnancy and birth rates. Clinics who do not comply with the policy will be subject to enforcement action, in line with the HFEA’s Compliance and Enforcement policy. This will be a series of escalating steps that may include a management review meeting and ultimately consideration by a HFEA Licence Committee.
In addition to these requirements, the HFEA Code of Practice also limits the number of embryos a clinic can transfer to two embryos in women under 40 and three embryos in women 40 and over.
The National Institute for Health and Clinical Excellence (NICE) Clinical Guideline on fertility treatment, published in February 2004, states that women aged between the ages of 23 and 39 should be offered three full cycles of IVF. A full IVF treatment cycle includes both the initial fresh embryo transfer and subsequent frozen embryo transfers.
The NICE guideline on fertility treatment is currently under review.