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Male Infertility

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MYTH: If men ejaculate, they are fertile. TRUTH: Ejaculation doesn’t mean fertility. Men can still ejaculate with a low sperm count or poor-quality sperm. Diagnosis requires a physical examination and semen analysis.

If you’ve been trying to conceive for a while, you may be wondering why your partner isn’t pregnant yet.

Learn what factors can influence your fertility and whether to consider seeking medical help.

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What is infertility?

It may come as a surprise if you’ve spent most of your adult life trying to avoid it, but conceiving is actually a lot harder than you may expect. So, if you’re finding it difficult to have a baby, you’re not alone. In fact, nearly 1 in 10 people struggle with infertility.1

Infertility is medically defined as the inability to conceive after 12 months of unprotected sex.1,2 However, if your partner is 35 years old or over, you as a couple may be considered infertile if you haven’t conceived after 6 months of unprotected sex.3

Sometimes, a couple who’ve already had a child can have trouble conceiving again. This is called secondary infertility.

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Is it my fault?

There are many factors that may be causing your fertility difficulties.

Around 1/3 of infertility cases are caused by fertility problems in women1
1/3 of infertility cases are due to fertility problems in men1
1/3 of infertility cases are caused by a mixture of male and female problems, or by problems that cannot be determined1

Infertility doesn’t necessarily mean that you won’t ever have children, but you may need the help of fertility treatment to conceive.

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What are the causes of infertility?

Your doctor will carry out a series of tests to diagnose what’s causing your fertility difficulties.

There are many reasons why you may have problems conceiving, including:

Your sperm does not have the concentration, motility or shape required to conceive
Existing medical conditions that affect your fertility, such as issues with sperm production or duct obstructions
Your sperm may not be strong or healthy enough to fertilise your partner’s egg
As your partner gets older, her fertility quickly declines3

Depending on the cause, your doctor will recommend a treatment path for you.

Frustratingly, sometimes there may be no clear reason and you may be diagnosed with unexplained infertility. In this case, your doctor may recommend advanced fertility treatment – assisted reproductive technologies (ART) treatment.

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Optimal sperm conditions

Although only one sperm is needed to fertilise your partner’s egg, the enzymes from multiple sperm are needed to break down the egg’s protective barrier.

In order to conceive, your sperm must be:

Highly concentrated: normally, there should be at least 15 million sperm in every ml of semen5
Moving well (motile): a lashing tail helps your sperm to swim to your partner’s egg
Normally shaped: healthy sperm should be shaped like a streamlined tadpole

You may find that your semen contains a very low number of sperm (oligozoospermia), or no sperm at all (azoospermia). In this case, your doctor may recommend surgically extracting sperm from part of your reproductive tract to help you to conceive.

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Sperm production problems

One of the most common causes of male infertility is problems with sperm production.

There are a number of sperm production problems that can contribute to infertility, including:

Scrotal varicose veins (varicoceles)
Scrotal varicose veins (varicoceles) are swollen veins causing your testicles to get hotter and affect the production of sperm
These are treated with surgery

Testicular injury
Serious trauma to the testicles such as becoming twisted (torsion) can affect sperm production
Damage from playing sports or an accident can rupture the vessels that supply blood to the testicles
Previous injuries can’t be treated, but an ART treatment may help you to conceive

Undescended testicles
In the uterus, baby boys’ testicles form in their abdomen and descend into their scrotum shortly before birth
Some men’s testicles don’t descend before they are born (cryptorchidism), although in these cases they usually drop in the first six months after birth
If left untreated, undescended testicles can affect fertility

Testicular cancer
This happens when a malignant tumour in the testicle destroys testicular tissue
If undetected, testicular cancer can spread to other parts of the body
This is treated either by surgery, medication, radiotherapy or chemotherapy
However, cancer therapy can also damage sperm production

Genetic defects
Sometimes, genetic information on the Y chromosome (which is only present in men) is deleted (micro-deletions),6 which can reduce the production of sperm
Depending on where the micro-deletion is on the chromosome, this may be treated by surgically extracting sperm from part of your reproductive tract
However, some couples may need to consider using a donor sperm to conceive

Contracting mumps (or mumps-related orchitis) after puberty may damage the sperm-producing cells in your testicles, causing infertility or subfertility7
Usually, only one testicle is affected and if you have one functioning testicle you may not need treatment
However, some couples may need to use a sperm donor in order to conceive

Anti-sperm antibodies
Anti-sperm antibodies are large proteins in your blood that are hostile to sperm
They can cause sperm to clump together and prevent them from swimming, or they may mistake sperm cells for an infection and try to destroy them
This can be treated using an ART treatment

Sperm production can be affected by a range of lifestyle factors, including smoking, drinking, drugs, stress, overweight and unhealthy food
Environmental factors can also affect your sperm quality, including overheating of your testicles, some sexual lubricants, the chemicals involved in certain manufacturing, painting or printing jobs
These factors are treated by making lifestyle changes, such as wearing loose clothing to avoid overheating

Hormonal problems
Hormonal problems are rarely the cause of male infertility problems
However, some men have a natural deficiency in follicle-stimulating hormone (FSH) and luteinising hormone (LH), which prevents the testicles from producing testosterone or developing healthy sperm
Hormonal problems can usually be treated with medication

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Obstruction problems

Blocked sperm ducts
Occasionally, male sperm ducts (epididymis and vas deferens) can become blocked, meaning that your semen doesn’t contain any sperm
This can be treated with surgery, or sperm may be surgically extracted from part of your reproductive tract

Some men have had a previous vasectomy to stop them being able to reproduce
This can sometimes be reversed using surgery
The procedure’s success depends on how long ago your vasectomy was performed

Previous infections
Infections can cause scarring or adhesions (organs sticking together) in your sperm ducts
This can usually be treated with surgery

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Does age affect male fertility?

Unlike women, whose fertility significantly declines after the age of 35, men’s fertility doesn’t decline until they are much older. Although sperm quality deteriorates as men age, this does not create a problem until after the age of 60.3

Learn more about how age can impact your fertility, and why it’s best to seek advice to conceive as early as possible.

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Are there any symptoms?

In the majority of cases, there are no obvious symptoms that you may be infertile. Usually, you’ll still be able to maintain erections and have sex, and the quantity and appearance of your semen will also be normal.

If you’re worried about your fertility, the best thing to do is talk to your doctor. They’ll recommend some simple fertility tests, more information about which can be found further below.

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Can I still father a child?

Over the past three decades, huge advancements in fertility science have helped millions of couples to overcome their difficulties and have children of their own.8
However, if your doctor diagnoses you with infertility, then it’s likely that you’ll need some additional help to conceive.

This may be as simple as timing when you have sex, or you may need more advanced fertility treatment.

Discovering that you’re infertile can be overwhelming, but the right support can help you to conceive successfully. Understanding what’s causing your fertility difficulties can help you find out what treatment is right for you and your partner.

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Fertility tests for men

Many couples have difficulty conceiving at first.1 If you’re seeking help to have a baby, you’ll need to undergo a range of fertility tests. Know what to expect from each test.

What are fertility doctors testing for?

There are many reasons why you and your partner may be struggling to conceive. Fertility testing helps your doctor to diagnose why you’re finding it difficult, and to develop a personalised fertility treatment plan for you.

Your fertility doctor will check that you have:

The right balance of hormones for sperm to develop
Good quality and quantity of sperm
A healthy, functioning reproductive tract
Unblocked sperm ducts

Your partner will also be tested to check that she is ovulating regularly and has a healthy reproductive system.

Who performs the fertility tests?

Your fertility team will perform any tests that you require. This team is made up of a range of doctors and fertility nurses, which may change depending on the support and treatments that you need. Sometimes, they’ll work together in the same fertility clinic. Other times, you may need to visit specialists at other clinics or hospitals.

Usually, you’ll begin with your family doctor who can perform some basic examinations and blood or urine tests. You may then be referred to a male reproductive specialist (urologist or andrologist), or directly to a fertility clinic, for further tests or treatments.

Inside a fertility clinic, there are a team of specialists, such as reproductive endocrinologists (REs) and embryologists, who oversee more complex treatments such as in vitro fertilisation (IVF).

Every fertility journey is different. Ask your doctor or fertility team in the clinic about their roles and how they will be supporting you.

Your fertility and sex life can be sensitive topics, and it’s important you feel able to ask any questions. Make sure that you choose a specialist you feel comfortable having these conversations with.

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Common preliminary fertility tests

Personal history
You will be asked about your medical history and sex life in detail.9 If you feel uncomfortable discussing anything in front of your partner, you can speak with your doctor in private.

Physical exam
Your doctor will usually examine your penis, your testicles and your prostate gland (via your rectum) to check for any abnormalities.10 Your doctor will be looking for varicose veins around your scrotum (varicoceles) which can affect fertility. They will also check that your sperm ducts (epididymis and vas deferens) are present and intact.

Blood and urine tests
You can be tested for rubella (German measles), hepatitis B and C and human immunodeficiency virus (HIV).9 Depending on your heritage, you may also be tested for diseases or disorders that are more common amongst certain ethnic groups, such as sickle cell anaemia or thalassaemia.

Semen analysis
You may be asked to provide a semen sample. This is done by masturbating either at home or at your clinic. The quality and volume of semen will be tested, including sperm count, concentration, movement (motility), size and shape (morphology) of your sperm.10

Testicular biopsy
A testicular biopsy may be performed if no sperm have been seen in your semen sample.10 You will be given an anaesthetic and your doctor will remove a small sample of tissue from one of your testicles. This sample will be tested to see if it contains any sperm that can be used in fertility treatment.

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More advanced fertility tests

Ultrasound scan (transscrotal ultrasound)
This scan shows any blockages or varicoceles around your testicles or sperm ducts that could be causing your infertility.11 Your doctor will pass a small device back and forth over your scrotum to pick up soundwaves, which are converted into an image. The transscrotal ultrasound is non-invasive and painless.

Transrectal ultrasound
This scan shows a more thorough overview of your prostate, the glands which produce your semen (seminal vesicles), and the sperm duct which carries sperm from your testicles to your urethra (vas deferens).11 Your doctor will insert a thin probe into your rectum while you lie on your side. Most men find this painless, although you may find it a little uncomfortable temporarily.

Further semen analysis
If your initial semen analysis results are abnormal, you may need to provide another semen sample. Your doctor will check that enough sperm are alive, and that there are no antibodies or infections in your semen.10

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Next steps

It’s natural to want answers straight away but unfortunately, fertility testing can take some time. It can sometimes take months for you and your partner to perform all the necessary tests.

Unfortunately, even after testing, some couples find that the reasons for their fertility difficulties remain unknown and they will be diagnosed with unexplained infertility.

It’s important to try to remain positive during this time. Getting a diagnosis is an important step forward in defining the right treatment to help you conceive.

Medical References

1. Boivin J, et al. New Debate: International estimates of infertility prevalence and treatment-seeking: potential need and demand for infertility medical care. Hum Reprod. 2007; 22(6):1506–1512. 2. World Health Organization (WHO). Sexual and reproductive health: infertility definitions and terminology. Available at Accessed September 2016. 3. American Society for Reproductive Medicine (ASRM). Age and fertility. A guide for patients. 2012. Available at: Accessed: February 2018. 4. American Society of Reproductive Medicine (ASRM). Causes of Infertility. Available at Accessed September 2016. 5. National Institute for Health and Care Excellence (NICE). Fertility problems: assessment and treatment: CG156. August 2016. Available at Accessed September 2016. 6. Speroff L. Male infertility. Clin Gynecol Endo Infertil. 1999;8:452–459. 7. Davis N, et al. BJU Int. 2010;105(8):1060–1065. 8. European Society of Human Reproduction and Embryology (ESHRE). ART fact sheet. Press information. Available at Accessed September 2016. 9. National Institute for Health and Care Excellence (NICE). Fertility problems: assessment and treatment: CG156. August 2016. Available at Accessed September 2016. 10. European Association of Urology (EAU). Guidelines on Male Infertility 2015. Available at Accessed September 2016. 11. Kliesch S. Euro Uro Suppl. 2014; 13(4):73–83.

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