The research presented at the virtual meeting of the European Society of Human Reproduction and Embryology 2020 followed 879 young female patients (mean age 33.8) over a period of 19 years (2000-2019) – the longest reported follow-up of fertility preservation in cancer patients.
'Currently, there is limited long-term outcome data [on fertility preservation] and this makes it difficult to counsel patients about the likelihood of success.' said study author Dr Dalia Khalife from Guy's and St Thomas' Hospital, London. 'Our study offers the largest cohort and longest follow-up of fertility preservation in female cancer patients… Around one in six of those who stored their gametes had a good outcome.'
However, she noted that there is a need for longer follow-up of patients and that early referral for fertility treatment is vital.
After counselling, 373 patients (42 percent) chose to have fertility preservation using one of three fertility preservation techniques: egg freezing (53 percent), embryo freezing (41 percent) and ovarian tissue cryopreservation (1%); with 5% using both egg and embryo freezing.
A total of 61 patients (16.4 percent) returned to use their eggs and 44 of them were successful following fertility treatment (live birth rate 72.1 percent). Women diagnosed with breast cancer were the most likely to return for treatment and also had the highest live birth rate (70 percent versus 30 percent for lymphoma patients).
'A fertility preservation service must be integral to a modern cancer care pathway. Fertility preservation with eggs and embryos has been beyond experimental for some time. And it's important that clinicians across the world continue to collect and share data on long-term outcome for all methods, including ovarian tissue preservation, to provide patients with robust information' said Dr Khalife.
Commenting on the study, Dr Melanie Davies, consultant obstetrician and gynaecologist at University College London Hospitals NHS trust and chair of Fertility Preservation UK, told BioNews:
'This is fantastic news – proof positive that fertility preservation is effective and worthwhile. It gives excellent outcomes for those women who return to use frozen eggs/embryos, as 44 of 61 achieved successful pregnancies and births. The proportion of patients who came back to the fertility clinic to use their frozen eggs/embryos (16 percent) is notably higher than for men who store sperm. More will return as the years pass. These results confirm that young women with a new diagnosis of cancer should be offered fertility preservation as part of their treatment pathway as long as they are well enough and time allows.'