Assisted Reproduction · Registries and Reporting
RRM Academy Synopsis
UK IVF multiple births fell from 28% to 6% between 1991 and 2019
The UK fertility regulator's 2022 registry report finds that the UK IVF multiple birth rate fell to 6% in 2019 from 28% in 1991, among cycles with a recorded outcome. Single embryo transfers rose from 13% to 75% of IVF cycles over those years.
Key Findings
- The UK's average IVF multiple birth rate was 28% in 1991 and 6% in 2019. The 10% national target was first reached in 2017.
- Single embryo transfers were used in 13% of IVF cycles in 1991 and 75% in 2019. For patients aged 18-35, use rose from 13% in 2007 to 83% in 2019.
- In 2015-2019, cycles with single embryo transfers had multiple birth rates around 1-3% at all ages. With the patient's own eggs and double transfers, rates topped 30% at ages 35 and under.
- Double embryo transfers with donor eggs produced a multiple birth rate near 30% at all patient ages in 2015-2019.
- Preterm birth (under 37 weeks) affected about 60% of IVF twin births in 2015-2019, against 9% of singleton births.
Interpretation
The report is a descriptive summary of national registry data from licensed UK clinics, grouped by the year treatment started. The HFEA states that its Register limits the analysis and that more research is needed on the factors behind decisions to transfer more than one embryo. Differences by age, ethnic group and funding are averages, and the authors call their causes likely or possible. The rates cover IVF only and omit cycles with no recorded outcome.
RRM Context
The report attributes multiple births from IVF largely to transferring more than one embryo to the womb, a clinical practice of the IVF procedure. IVF bypasses the reasons conception fails without resolving them. Restorative reproductive medicine begins by evaluating both partners to find and treat those causes. The report lists stillbirth, neonatal death and cerebral palsy among the added risks of a twin pregnancy.
Abstract
Multiple births in fertility treatment 2019 presents UK multiple birth statistics for IVF and DI fertility treatment. The report describes HFEA measures to reduce multiple births, including restrictions on triple embryo transfers introduced in 2003 and the ‘One at a time’ campaign launched in 2007. The report states that the average UK multiple birth rate from IVF treatment decreased from around 28% in the 1990s to 6% in 2019, and that single embryo transfers increased from 13% of IVF cycles in 1991 to 75% in 2019. The report also states that about 60% of IVF twin births were preterm (under 37 weeks) compared to 9% of singleton births from 2015-2019, and sets out actions for the HFEA, clinics and others.
