- A review of the evidence found men with diabetes have a higher risk of infertility
- A stronger link was seen in people type 2 diabetes
- The authors point to ongoing inflammation as a likely reason – including higher levels of inflammatory markers such as TNF alpha
A large review of published research suggests diabetes is linked with a higher risk of male infertility.
Published in Frontiers in Endocrinology, the analysis pulled together decades of studies to understand how diabetes might affect male reproductive health and what could be driving the problem.
Diabetes – whether type 1 diabetes or type 2 diabetes – is usually discussed in terms of heart health, kidneys, eyes and nerves.
Fertility is talked about far less, but for men of reproductive age it can be a real concern.
This review adds weight to the idea that long term metabolic health can affect sperm and reproductive hormones.
- Adopting a Mediterranean diet improves fertility, evidence suggests
- Disease-causing mutations in sperm cells increase as men age
What did the researchers do?
The authors carried out a systematic review and meta analysis using standard methods for evidence reviews.
They screened more than 350 papers and included 17 observational studies looking at infertility in men with type 1 diabetes and type 2 diabetes.
The studies covered research published between 1972 and 2022.
What the research found
Across the combined results, men with diabetes were more likely to have infertility than men without diabetes.
When the researchers split the findings by diabetes type, the association looked stronger for type 2 diabetes than for type 1 diabetes.
The review cannot prove that diabetes directly causes infertility because the included studies were observational.
Still, the results were broadly consistent across different populations.
Inflammation
To explore what might be going on biologically, the authors also looked at studies focused on inflammation and at gene activity data linked to fertility and testicular function.
A recurring theme was higher levels of inflammation related signals in men with diabetes.
One example mentioned was TNF alpha, an inflammatory marker that has been linked with a range of diabetes related complications.
The gene level analyses also suggested changes in inflammatory signalling alongside changes in genes involved in fertility and testicular health.
- High blood sugar levels associated with increased risk of infertility among men
- Fertility problems higher amongst women with bigger waist circumference
Taken together, the authors argue that inflammation could be one of the key links between diabetes and poorer male reproductive health, particularly in type 2 diabetes where insulin resistance and metabolic strain are common.
What you can do if you are worried
If you have diabetes and you are trying to conceive, do not assume you just need to wait it out.
Practical steps include:
- Speak to your GP or diabetes team and explain how long you have been trying
- Ask whether a semen analysis and hormone blood tests are appropriate
- Focus on the basics that support both diabetes management and fertility such as glucose control, weight, sleep, physical activity, smoking cessation and keeping alcohol within guidelines
