Attempting to investigate possible reasons for the decline in pregnancy rates for older women who undergo IVF, a team of researchers have published their work in the Journal of Endocrinology. In a specific type of cell which surrounds the egg they report the expression of several genes to be different between older and younger women, and also that this cell type replicated less frequently in older women.
Dr Dusko Ilic, Reader in Stem Cell Science, King’s College London, said:
“Maturing egg cells are surrounded by granulosa cells, which play an active role in the egg’s development. The authors suggested that the change in these supporting cells over lifetime might contribute to the decline in fertility with age. Although the data are preliminary and more work has to be done to prove the hypothesis, the idea behind it is quite plausible. It is widely accepted that the microenvironment in which the cell, in this case the egg, resides is important for the cell’s function and survival. The authors also presented preliminary evidence that retrieving maturing eggs earlier than the standard practice is today might improve IVF outcomes in older women. Although the initial data are intriguing, caution must be exercised and the conclusions have to be proven in a larger study.”
Prof. Simon Fishel, Professor of Human Reproduction and Managing Director of the CARE Fertility Group, said:
“This study is limited in its outlook – by far the biggest concern for women over the age of 40 is the random anomalies in the chromosomes of their eggs. In women over the age of 43 up to 90% of their eggs may be chromosomally abnormal resulting in a failed implantation, increased miscarriage and low incidence live birth. This study does not even quote live birth rates, and, indeed, demonstrates no significant difference between embryos implanting from the control group. In addition, ‘going in early’ has been the main practice of clued-up IVF practitioners for many years, ‘premature luteinisation’ has been a known problem for 3 decades; the study simply provides further genetic and biochemical data in relation to this problem. In short, the small numbers in the study, the uncontrolled retrospective analysis, insignificant increase in implantation rates and no data on live births does not provide any evidence or further insight to indicate there is something of benefit to patients.”
Dr Darren Griffin, Professor of Genetics and Director of the Centre for Interdisciplinary Studies of Reproduction (CISoR), University of Kent, said:
“The paper itself describes what is reasonably convincing evidence of an age related skewing in the ratio of receptors for the ‘top two’ female hormones. Insights such as this are crucial for our understanding of age-related decline in ovarian function and its subsequent implications for IVF success. This is particularly relevant as older women seek IVF later in life of socio-economic reasons. What is more controversial is the suggestion towards the end of the paper that retrieving the eggs earlier during the developmental cycle could alleviate the problem. In medical terms this is promising, particularly if these results are borne out on a larger sample population. In one sense it stands to reason that such ‘younger’ eggs might ‘work better’ in an IVF setting. The problem lies here however in the further studies that are needed to ask the question of whether an egg that might be considered ‘under-ripe’ might have other problems associated with it. These need to be examined in more detail before the procedure is put into routine use.”
‘Aging-related premature luteinisation of granulosa cells is avoided by early oocyte retrieval’ by name of Yanguang Wu et al. published in Journal of Endocrinology on Wednesday 12th August 2015.
All our previous output on this subject can be seen at this weblink: http://www.sciencemediacentre.org/tag/ivf/
The SMC produced a Factsheet on IVF and fertility which is available here: http://www.sciencemediacentre.org/ivf-and-fertility/
Dr Dusko Ilic, Dr Darren Griffin: no interests to declare
Prof. Simon Fishel: “I am a shareholder in CARE Fertility, but have no links to this article.”