Causes & Treatment

Multiple Births – The Latest UK Figures

Eloise Edington | 12 Feb 2021

Words by Sophie Braybrook

IVF Multiple Birth Rates Drop Three-Fold in 10 Years – But Remain Dangerously High

Latest figures show that IVF multiple birth rates have decreased to 8%, achieving and exceeding the 10% target set by the UK fertility industry. Over the 10 years from 2008 to 2018, multiple birth rates through IVF have made a three-fold reduction, a feat that, at a glance, seems very impressive.

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What’s the Reason for this Reduction?

The Human Fertilisation and Embryology Authority (HFEA), the executive non-departmental public body of the Department of Health and Social Care, has encouraged licensed fertility clinics to reduce the incidence of multiple births following IVF. HFEA’s actions followed research chaired by Professor Peter Braude in 2007 which advised that IVF multiple births rates should not exceed 10%.

“Rather like a speed limit,” Professor Braude said that“a 10% multiple birth rate is not a target but the upper limit that all fertility clinics should strive not to exceed. Most [clinics] have now achieved this and many have an even lower multiple birth rate,” Braude continued. “If this process is maintained, multiple birth rates from IVF in the UK will continue to fall and many families’ lives will be changed for the better.”

Risks of Multiple Pregnancy

“Multiple pregnancies carry increased risk of complications, including anaemia, pre-eclampsia and gestational diabetes,” Dr Suvir Venkataraman, General Manager at Harley Street Fertility Clinic explained. In fact, multiple pregnancies are the greatest risk from IVF to mothers and babies, and a major cause of stillbirth, neonatal death, premature birth and disability.

Is the Current 8% Rate Low Enough?

NHS figures show that “about 1 in every 65 births in the UK today are twins, triplets or more,” that’s a 1.5% multiple birth rate (as demonstrated in fig.2 below). Considering this figure includes assisted conception, which sits at 8% (fig.3), the natural multiple birth rate will be even lower than this 1.5% figure.

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Why is there such disparity between the natural and aided multiple birth rates? Most IVF multiple births occur when embryologists transfer multiple embryos, in an attempt to increase rates of successful IVF births. So, considering this number can largely be controlled and the side effects can be so damaging, should fertility clinics still aim to operate at the 10% outlined in Braude’s work, or should that number be lowered to closer match the natural multiple birth rate?

Science Practitioner at IVI London Eleanor Gallegos explained the financial and emotional reasons patients may choose a double embryo transfer: “One cycle costs around £1,500” and “coming in for a transfer and having it fail is hugely difficult to deal with for a lot of patients, so putting two [embryos] back would increase the chance of success and help take away the emotional and financial distress of having a failed cycle.”

Eloise Edington, a fertility warrior who founded Fertility Help Hub after she and her partner faced fertility struggles, opted for double embryo transfers for each of her three cycles and fell pregnant with twins during their final round and were delighted. Despite experiencing some of the negative effects of multiple pregnancies, including having a c-section at 37.5 weeks, Edington said: “we were glad we had twins, as we were on our last embryos and my husband didn’t want to do another round.”

Suzanne Cawood, Head of Embryology at CRGH, explained that they most often advise the transfer of a single embryo, but that, as with Edington, their “patients who have had several failed IVF attempts sometimes choose to have two embryos replaced in the hope of increasing their chances of a pregnancy.” Cawood added; “We should bring the multiple birth rate in line with the same rate as natural conception…this could be achieved by reducing the target incrementally; a new target of 5% could be introduced initially.”

Matching IVF with the Natural Multiple Birth Rate

Upon a brief analysis of IVF multiple birth rates over the last decade, the three-fold reduction seems an impressive. However, on closer inspection, there’s a clear need for this 8% rate to reduce further. While in Edington’s case, a multiple birth had a largely positive impact as she was able to complete her family in one final cycle, even her pregnancy came with complications. It seems that the industry recognises the seriousness of the risks of multiple births and supports the need for the IVF multiple birth rate to reduce still.

The HFEA offered the following statement: “We know that multiple births are the biggest single health risk from IVF for mothers and babies and put an additional burden on the NHS. That’s why it is a great achievement that our 10% multiple birth rate target was achieved across all age groups and nationally only 8% of IVF births resulted in a multiple birth, making fertility treatment now safer than ever before.”