Results from a Spanish study presented at the meeting of the European Society of Human Reproduction and Embryology 2021 showed that in patients with low ovarian reserve, the protocol – called DuoStim – resulted in a comparable number of eggs and embryos as two rounds of egg collection in separate cycles. However, with DuoStim the average time it took to have an embryo ready for transfer was reduced.
'We think it's a great alternative for predicted poor responders who might otherwise have difficulties reaching blastocyst transfer from just one egg pick-up' said Dr Maria Cerrillo Martinez from IVIRMA in Madrid, Spain who presented the findings.
DuoStim entails two ovarian stimulations and egg collections during a single menstrual cycle. Historically, fertility treatment has involved a single ovarian stimulation and egg retrieval in a given cycle. This would normally be during the first half of the cycle (the 'follicular' phase) but there is precedent for collecting eggs in the second 'luteal' phase, such as for women needing fertility preservation prior to cancer treatment, when delaying treatment until the next cycle would not be justifiable.
Dr Cerrillo and her team conducted a randomised trial, comparing DuoStim with results from two rounds of stimulation and egg collection on separate cycles. All 80 participants were aged 38 or older and had predicted low ovarian response to stimulation. The DuoStim group had a chromosomally-normal embryo ready for transfer on average 23 days after the start of stimulation, whereas the average was 44 days in the conventional method group.
The researchers do not recommend DuoStim for patients who respond well to ovarian stimulation, as they are likely to produce enough good-quality eggs. However, Dr Cerrillo recommended several classes of patients who could benefit:
'It may be a good alternative in poor responders, in fertility preservation patients with time constraints, or even in egg donors, whose aim is to maximise the number of eggs retrieved in a single treatment,' she said.