Time Waits for No Man: The Impact of Age on Male Fertility

Progress Educational Trust
Great Hall, Royal College of Physicians of Edinburgh, 9 Queen Street, Edinburgh EH2 1JQ
9 May 2018
This public event was organised by the Progress Educational Trust (PET) and supported by the Scottish Government, and was held at the Royal College of Physicians of Edinburgh.
It has been 40 years since the American journalist Richard Cohen first popularised the phrase 'biological clock', as a way of conveying the decline of fertility with age. This phrase was originally used exclusively in relation to women, but is now increasingly used in relation to men.
Men's biological clocks are not as obvious as those of women - sperm is produced on an ongoing basis throughout a man's life (whereas a woman's lifetime supply of eggs is produced before her birth), there is no definitive 'manopause' beyond which men cannot conceive, and there is no monthly cycle to remind men that their clock is ticking. Nonetheless, age does have a drastic and underappreciated impact on male fertility.
Both the quantity (semen volume and sperm concentration) and the quality (motility and morphology) of sperm produced by a man will diminish with his age - sooner or later, it may become more difficult for him to conceive a child. Men who are fertile early in life may become subfertile or infertile in later life, while men who are already subfertile early in life are liable to see their fertility decline even further.
When an older man does succeed in conceiving a child, the difficulties posed by his age may not be over. Greater age brings an increase in the number of mutations in a man's sperm, which in turn can threaten the health of the pregnancy (there is an elevated risk of miscarriage) and the health of any resulting child (there is an elevated risk of the child having congenital disease or a psychiatric condition).
Questions explored at this event included:
How can people - men and women alike - achieve a better understanding male fertility in the round, including the way subfertility can be offset or exacerbated by other factors? For example, a man's subfertility may not be an impediment to conceiving a child if he and his female partner are both young, but may become much more of a problem if one or both of them are older.
Should male age be a criterion when judging a couple's eligibility for NHS-funded fertility treatment, as is the case with female age? Is this a logical corollary of the fact that there is a recommended upper age limit for sperm donors in the UK, or would it be an overreaction to the risks and challenges of older fatherhood?
Is age relevant to the advisability of a man cryopreserving (freezing) his sperm, either in anticipation of a natural decline in his fertility or ahead of medical treatment that will compromise his fertility (such as cancer treatment)? Should the age at which a man is permitted to do this, or the age at which he can receive public funding to do this, be limited?
How does the fertility of older men relate to their health more generally? Decreasing quantity and quality of sperm is associated with increasing risk of various diseases, as well as a shortening of life expectancy, but it is not clear whether the decline of male fertility is a cause or a consequence of these other factors.

Allan Pacey
Trustee at the Progress Educational Trust (PET), and Professor of Andrology at the University of Sheffield
Christopher Barratt
Professor of Reproductive Medicine and Head of the Reproductive Medicine Group at the University of Dundee's School of Medicine
Richard Sharpe
Honorary Professor and Principal Investigator at the University of Edinburgh's Centre for Reproductive Health
Dr Sarah Martins Da Silva
Consultant Gynaecologist at Ninewells Hospital and Medical School's Assisted Conception Unit, and Clinical Lecturer In Reproductive Medicine at the University of Dundee's School of Medicine

Dr Jane Stewart
Chair of the British Fertility Society, and Head of the Newcastle Fertility Centre at the Centre For Life

Partners and supporters: