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unexplained infertility
Conception Mar 11, 2021
4 Minutes

4 potential causes of ‘unexplained’ infertility

We know that infertility is on the rise. We also know that ‘unexplained infertility’ impacts 30% of those struggling to conceive. It can also be a devastating and frustrating diagnosis. Traditional testing can miss some potential contributors. We take a look at four things that are worth further investigation: 

Unexplained infertility impacts 30% of couples struggling with fertility: 

Common reasons for infertility include: 

  • tubal/cervical malformation 
  • Issues with ovulation
  • endometriosis
  • Chromosomal abnormalities (often age/lifestyle related) 
  • Lower sperm quality

However, around 30% of couples do not have any of the issues above yet still struggle to conceive. 

As always, there are many potential reasons. Here are 4 that may be missed by conventional testing: 

How a ‘normal’ thyroid test can actually be not normal at all: how this can contribute to unexplained infertility:

Traditional thyroid tests will look at TSH – aka the Thyroid Stimulating Hormone. A high level indicates that there could be a problem. The trouble is that the definition of what is ‘high’ is not agreed upon. Even more a ‘slightly high’ number can have no symptoms. Yet, research increasingly points to abnormal thyroid levels being a contributor to infertility and miscarriage. 

Some doctors class anything below 5.0ml U/L as ‘normal’ however, the Endocrine Society Practise Guideline recommends investigation of a preconception TSH level above 2.5ml U/L.

Ask for a test and ask for your results. If it is above 2.5ml U/L this could indicate subclinical hypothyroidism. This is worth discussing with your doctor. Medication of this has led to an improvement in conception/pregnancy rates. 

Also worth checking is for antibodies (not tested as standard). Antithyroid peroxidase (TPO) antibodies alongside a subclinical thyroid issue = highest risk of adverse pregnancy outcomes. 

For MUCH more on the topic – click here. 

How a ‘normal’ semen analysis can actually be behind unexplained infertility: 

Traditional semen tests look at things like count, morphology (shape) and motility. All important stuff. However, it misses a crucial part: how much of it is ‘genetically normal’. Without enough genetically normal sperm you are at risk of infertility and increased risk of miscarriage. 

Think of it like egg quality – but for sperm. 

Semen DNA can be damaged by age, lifestyle or hidden conditions like Varicocele. 

A number above 30% may well be a contributing factor behind unexplained infertility. Lifestyle change, diagnosis and treatment of Varicocele or using techniques like ICSI during IVF can eliminate it as an issue. 

Click here for much more. 

Chronic inflammation: a potential contributor to unexplained infertility:  

Inflammation is the body’s response to ‘attack’. In small doses against certain ‘predators’ it is absolutely vital for survival. However, when the body is constantly fighting, as is the case for chronic inflammation, it can cause peripheral tissue damage. The scientific community is increasingly recognising it as a major root cause of many chronic illnesses today. Infertility being one of them. Sperm and egg cells are particularly vulnerable. 

We also know it has steadily been on the rise given our shifting lifestyles. 

Contributing factors:

  • diet (high in fat/simple sugars/low in fibre/nutrients)
  • high BMI
  • lack of physical exercise
  • chronic psychological stress
  • Vitamin D deficiency
  • Microbiome depletion
  • Air pollution 

So what to do? 

A test known as C Reactive Protein test will indicate potentially elevated levels of inflammation in the body. The next step is to target a potential cause. As always knowing your enemy is part of the battle.

For much more and how to treat it – click here. 

Vitamin D deficiency: a potential contributor to unexplained infertility: 

We know that many of us are deficient. Time spent indoors, better understanding of skin safety, sedentary lifestyles and the fact that you cannot acquire it from diet = higher risk of deficiency. 

The trouble is more and more research suggests that there are longer term consequences of deficiency. Male and female fertility included. 

For a deep dive on what we know – click here. 

Vitamin D is actually a steroid hormone. Research has shown a tangible effect on male fertility – largely related to semen quality and motility. 

We also know it plays a crucial role in protection of sperm against DNA fragmentation caused by oxidative stress (something sperm cells are particularly vulnerable to). 

It even appears to play a role in implantation. There is a specific molecule involved in implantation (HOXA10) that is regulated by the active form of Vitamin D (D3) in human endometrial cells. So ensuring you have enough is key. 

Bottom line: 

As with many things in the body; there can be many potential reasons behind infertility. The body is in delicate balance and modern life does a great job at pushing that off. The good news is that once you identify issues you’re much closer to finding solutions. Unfortunately many standard tests miss some of the factors described above. If you’re struggling, don’t be afraid to push for more information about your body. After all knowledge is power. Knowing your enemy is half the battle. 



This article is for informational purposes only. This article is not, nor is it intended to be, a substitute for professional medical advice, diagnosis, or treatment and should never be relied upon for specific medical advice. The information on this website has been developed following years of personal research and from referenced and sourced medical research. Before making any changes we strongly recommend you consult a healthcare professional before you begin.





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