Advances in IVF techniques are offering more patients the chance of a successful pregnancy while making treatment safer, according to research presented at the recent Annual Meeting of the European Society of Human Reproduction and Embryology (ESHRE).
Before the risks of multiple embryo transfers were fully understood, many fertility specialists believed that transferring more than one embryo during IVF increased the likelihood of achieving a successful pregnancy and live birth.
However growing evidence showed that transferring multiple embryos significantly increases the risk of complications for both mother and babies, and it became recognised that these risks often outweighed the potential advantages.
Now a major new study*, one of the largest of its kind, has found that contemporary techniques can improve the chances of successfully having a baby while significantly reducing the likelihood of twin and triplet pregnancies.
The researchers analysed outcomes from over 18,000 women undergoing their first IVF cycle between 2012 and 2021, at seven different clinics across Australia.
They found a cumulative live birth rate of 68.2%, over three treatment cycles, with over 95% of the transfers involving single embryo transfer, and a multiple birth rate of under 3%. By comparison, historical studies had demonstrated a live birth rate of up to 59% with multiple pregnancy rates in excess of 20%.
The study attributed these changes to the implementation of modern clinical practices such as blastocyst culture (developing embryos in the laboratory until day 5/6 after fertilisation, rather than the traditional 2/3), embryo vitrification (rapid freezing of embryos which increases their chances of surviving freezing/thawing), and freeze-all cycles (embryos transferred one at a time after the initial stimulation cycle).
Commenting on the findings, Dr Luciano Nardo, Consultant in Reproductive Medicine & Infertility at NOW-fertility, concluded ‘These results highlight the need to continue advancing access to single embryo transfer globally, supporting safer and more effective fertility care for all.’
*[1] Morbeck, D., et al. (2026). Modern IVF clinical practices achieve superior cumulative live birth rates with near-universal single embryo transfer: A multi-cycle cohort study. Human Reproduction.
