By: Emily Hudson, University of Oxford Micro-intern at Jack Fertility
Fertility testing has become increasingly prominent over the last half-century. This blog aims to demystify the process: why we do it, and how it is done.
Why do we do fertility testing?
Over at least the last fifty years, societies across the world have seen a gradual decrease in birth rates. There are many factors that play into this, most of which cannot be tracked down to infertility. The two main causes are as follows:
Decline in infant mortality. Huge increases in the quality of healthcare and safeguarding against infant diseases mean that infant mortality is now treated as a tragedy and not the norm. As such, families are likely to have fewer children, as their children are more likely to survive infancy.
People are choosing to have children later in life. As women have become more integrated into the workplace, they have fewer children and have them later. Couples also tend to marry at a later age, with the average age fertility shifting from the “20-25” age category to “25-30” over the last century.
It is the latter point that can bring fertility testing into the mix. As people age, their fertility declines. This means that people trying to conceive for the first time nowadays are more likely to run into trouble than half a century ago – so fertility testing and treatment are becoming increasingly necessary.
For a person with sperm, fertility is measured by the quality of said sperm. We can define quality using 5 factors. Sperm quality can be affected by both age and lifestyle – in the case of lifestyle, this change is reversible as sperm is produced in a continuous process. Age becomes an important factor for people with sperm aged 45 and over. Lifestyle factors include diet, alcohol consumption and exercise – the same factors that affect overall health.
This is different to the case for those with uteruses, who are born with thousands of eggs. Not all of these eggs are optimal for fertilisation and pregnancy. The number and quality of eggs decline with age and, like sperm, with environmental factors too, such as stress. In women, age becomes gradually more important past the age of 35.
“Low quality” eggs and sperm have abnormalities or deformities, such as the wrong number of chromosomes. This can result in the embryo failing to implant on the walls of the uterus (leading to miscarriage) or genetic abnormalities which impact the chances of the pregnancy being (and remaining) healthy.
In recent years, scientists have also begun to consider the impact of climate change on fertility. The stresses of extreme weather events can compound that felt by those facing fertility difficulties, and make pregnancies harder. This is the changing landscape of our world: clearly, it will only become more important for people to test their fertility.
How do we do fertility testing?
Currently, fertility testing consists of sperm analysis for people with sperm and, for those with uteruses, factors ranging from at-home hormone analysis to anatomical examinations of the reproductive system. Until very recently, sperm collection and analysis was exclusively carried out in a laboratory environment, due to how poorly it survives outside the body.
Fertility treatment in some form or another has been around since at least the Victorian era, focusing initially on women and their anatomy: surgeries and other procedures that, like most other medicine at the time, had little scientific backing. In the 1870s or so, doctors turned their approach to men, and some of their advice does still hold true today: a healthy diet and abstention from smoking are well-known lifestyle factors that can boost sperm health. Nowadays, it is well-accepted that andrological and gynaecological infertility are two sides of the same coin, and must be considered in tandem.
Thankfully, modern science, and with it a more comprehensive understanding of how fertility works have led to the development of fertility tests and treatments that are (usually) far less invasive, and far more reliable.
Semen analysis typically considers five characteristics: volume, count, motility, morphology, and concentration. These summarise how much sperm there is, how well it can travel and how well-formed it is. This analysis is usually completed within 1 hour of semen collection. This can be embarrassing for the person being tested, combined with the added inconvenience of having to travel to a fertility clinic. Jack aims to take these barriers away and make fertility testing more accessible for those with sperm. Innovations in the last few years have made this possible by finding new ways to test semen.
Female fertility testing can include urine or blood tests analysing the levels of a range of hormones. Some of these tests (namely, ovulation tests) can be purchased over the counter and provide a baseline indicator. Usually, key hormones are looked at, which all fluctuate differently throughout the menstrual cycle. In testing, practitioners are looking for the correct balance between them all. Abnormal hormone levels, and other symptoms, can be indicative of conditions such as PCOS which do have a link to decreased fertility in those with uteruses.
For those with sperm, testing methods can be invasive at worst, and at best somewhat embarrassing for participants. A recent study notes that male infertility is “invisible” in society at large, with even those undergoing fertility treatment being unwilling to admit they are facing difficulties.
The sensitive nature of fertility can make it both one of the hardest and most meaningful issues to seek help for quickly. Mail-in testing ensures privacy, dignity, and convenience without compromising on quality. Repurposing existing technology, Jack Fertility brings the landscape of male fertility testing in line with the standards set by both the female counterpart and healthcare tests in general.
Emily Hudson is a third year Physics student at Oriel College, Oxford. She is the Deputy Editor and Lead for Science & Technology at The Oxford Student. The scientific portions of her post were reviewed by Maryam Rahbar, MSc DPhil (pending), Chief Scientific Officer at Jack Fertility.
 Toulemon L. Historical overview of fertility and age. Maturitas. 1988;Suppl 1:5-14. doi: 10.1016/0378-5122(88)90003-5. PMID: 3070307. (1988)
 Segal, Thalia R. et al. Systematic review of climate change effects on reproductive health. Fertility and Sterility, Volume 118, Issue 2, 215 - 223 (2022)
 Rahbar, M. The basics of semen analysis: what you need to know about sperm and how it is tested, Jack Fertility (2022)
 Barnes, L. "Male infertility is ‘culturally invisible’, finds research", University of Cambridge (2014)