Although fertility problems have often been considered a female problem, this isn’t always the case. Approximately half of all couples coming to the fertility clinic for evaluation find they have a problem with the man’s sperm.
Although this can often leave the male partner feeling bewildered and confused, it’s important to remember that infertility is a problem of the couple and is a shared challenge, no matter where the diagnosis lies.
The Male Reproductive System
The testes are the most important part of the male reproductive system. This is where the sperm are made and stored, as well as the site of testosterone production, the hormone that gives men their masculine characteristics and helps sperm development.
The testes are made up of very small tubules called the seminiferous tubules where the sperm mature. Nature has designed the anatomy of a man so that the testes are kept suspended away from the body; this is to keep them approximately 1 degree cooler than the rest of the body. In colder weather, the scrotum contracts to pull the testes closer to the body to maintain a constant temperature.
As the sperm mature, they pass from the testes into the epididymis, a tightly coiled tube at the top of the testes (stretched out it would be approximately six meters — about 19 feet — long!). Here, they further mature and develop their ability to swim. It takes approximately 12 weeks for the full cycle of sperm development and 10 to 15 days for them to travel to the end of the epididymis before entering the vas deferens.
The vas deferens is a long curving tube that carries the sperm from the epididymis up into the groin. Pouch-like glands called seminal vesicles at the far end of the vas deferens produce most of the fluid (semen) in the ejaculate.
A man who has had a vasectomy can still produce semen because the vas deferens has been cut close to the epididymis so that the seminal fluid can still leave the body, but the sperm stay trapped.
The prostate gland is the largest of all the male reproductive glands and lies just below the bladder. The prostate gland also produces some of the seminal fluid discharged into the urethra during ejaculation. This fluid helps to change the pH of the semen, which neutralizes the acidic environment of the vagina.
The Role of Sperm in Fertilization
After ejaculation, the sperm swim through the cervical mucus and enter the uterus. They then swim up into the fallopian tubes where they meet an egg at the far end closest to the ovary. Although millions of sperm are deposited in the vagina, only a couple of hundred reach the egg, and only a single sperm is needed for fertilization.
The sperm binds with the outer shell of the egg and enters it in a process called the acrosome reaction. As soon as this happens, the shell of the egg changes to stop any more sperm from entering. The DNA is then released from the head of the sperm and combines with the DNA of the egg to form the embryo.
Causes of Male Infertility
Sometimes the male partner is found to have a problem with his sperm. A semen analysis at your local fertility clinic will identify problems involving the sperm count (numbers) and morphology (the shape and size) or motility (the movement). If a specific problem is identified, then the cause can be investigated by a specialist. Most often the only advice is to change environmental and lifestyle factors that may be contributing to a low sperm count. But occasionally further testing is needed to eliminate underlying health conditions or undiagnosed genetic disorders.
Causes of fertility problems in men include the following:
- Obstructive problems (blockages in sperm-carrying tubes)
- Testicular injury and disease
- Varicocele (a varicose vein in the scrotum)
- Sperm disorders
- Genetic disorders
- Problems with erections and ejaculation
- Hormonal problems
- General medical disorders that reduce fertility
- Drugs that reduce fertility
- Environmental toxins and radiation
Sperm Quality Factors in Male Infertility
Sperm quality influences not only rates of fertilization but also subsequent embryo development. Remember, half of the genes come from the father. The male partner may carry a chromosomal abnormality that is responsible for him having a low sperm count and that increases the risk of implantation failure and miscarriage.
A standard semen analysis usually tests sperm count, motility, and morphology. Several tests that are more advanced can be carried out if the sperm count is low for no apparent reason or if several treatment cycles fail without explanation.
Several studies have shown increased sperm quality when a man takes vitamin supplements for a prolonged period. This is especially true if the supplement contains vitamin C, zinc, and folic acid. Eating a balanced, healthy diet with plenty of fresh fruit and vegetables, along with good quality proteins and healthy oils, has also been shown to improve fertility in men.
Interestingly, most of the sperm found in a man’s ejaculate is actually abnormal, even in men with normal fertility. This is a case where the body is focused on quantity rather than quality.
One of the first investigations done by a fertility doctor is a semen analysis. This is done by the man masturbating and collecting the semen into a sterile container. You can produce the sample at the clinic in a special room or at home if you live close by. The clinic will supply you with a container and sperm safe lubrication and so don't use any household products or this may affect the results.
When you get your semen assessment done, your doctor will receive a report from the lab with all the findings. The following table shows the normal ranges for sperm count, motility and morphology.
Interpreting a Semen Analysis
The following table shows the normal ranges for sperm count, motility and morphology:
|COUNT per ml (millions)||15||73||213|
|TOTAL COUNT (millions per ejaculate)||39||255||802|
|TOTAL MOTILITY (%)||40||61||78|
|PROGRESSIVE MOTILITY (%)||32||55||72|
|NORMAL FORMS (%)||4||15||44|
|VITALITY (% alive)||58||79||91|
Research shows that if you analyze the sperm of men whose partners got pregnant in 12 months or less, then the average sperm count (50th percentile) was 73 million per ml. The 5th percentile, which is the very low end, is often quoted as the “normal” cutoff at 15 million per ml.
Although it’s safe to say that some normally fertile men will have a sperm count of 15 million per ml, keep in mind this is the lowest end of the normal range and would be considered a poor result.
The most important results are the sperm count and motility and this will determine the suggested treatment options for the couple.
If the count is close to normal or just slightly low and the female partner has no known fertility problems, then the doctor may suggest an intrauterine insemination (IUI) cycle, where the sperm is concentrated into a small volume and placed directly into the uterus.
Beyond the Semen Analysis
Problems with the sperm not diagnosed by standard parameters of a semen analysis are:
- A balanced translocation (rearrangement of the chromosomes)
- Y chromosome microdeletions
- Cystic fibrosis gene mutations
- DNA fragmentation
- Aneuploidy (having the wrong number of chromosomes)
Advanced tests can detect problems with the genetic component of the sperm (inherited from the male) and may provide an explanation as to why the sperm count is low, embryo quality poor, or pregnancy isn’t achieved.
One test that can be done is a karyotype on the male partner, this and a blood test and will identity a balanced translocation that can cause miscarriages and failure to get pregnant through IVF. Y-chromosome microdeletions and cystic fibrosis gene mutations are also detected by analyzing the DNA of the male partner (also a blood test) but these tests are usually only done if the sperm count is very low or the man is found to be azoospermic (has no sperm at all in his ejaculate).
DNA fragmentation and aneuploidy (having the wrong number of chromosomes) are problems associated with the sperm itself and not the male partner's DNA. These issues can be detected by specialized tests, but because there is no cure (other than lifestyle changes) the doctor usually does not recommend testing the sperm DNA but instead recommends that the man adopts the lifestyle changes and takes anti-oxidants in preparation for conception.
Male Fertility and Aging
Research is beginning to show that as men age, their fertility starts to decline. This age-related decline in fertility is much more pronounced in women, so the effects of aging on sperm quality have not been studied as extensively. Women are born with all their eggs, which gradually diminish over time, whereas men are constantly making new sperm.
Even so, the fittest and healthy 50+-year-old men can have subtle changes in the number of sperm, the morphology of the sperm, and, in particular, the DNA contained in the sperm that contributes to the embryo. Studies have shown that semen quantity peaks between the ages of 30 and 35. Overall semen quantity was found to be lowest after age 55.
Sperm from older men has a higher rate of DNA fragmentation. Although some men can go on to father healthy children, there is an increased risk of miscarriage and an increase in the rate of birth defects seen in children born from older fathers. These birth defects include dwarfism, autism, and schizophrenia, among others.
What You Can Do to Improve Your Sperm Count
If you are found to have a low sperm count, usually no specific treatment or cure is available (unless surgery is required, for example, for a testicular varicocele or tubal blockage). Your doctor may investigate the reason for a low sperm count to eliminate any underlying health conditions.
If you are good health, the medical advice will usually be to evaluate any lifestyle changes you can make. While there are no magic cures to dramatically improve sperm quantity if a man has a healthy lifestyle and doesn’t drink or smoke, he will maximize his chance of having good quality sperm.
Keep in mind that it takes 12 weeks for sperm to be made in the body, so a healthy lifestyle should be adopted for at least three months before attempting conception or before a fertility treatment cycle begins.
Practical advice for men wanting to improve their sperm quality includes:
- Get a general medical evaluation
- Keep cool; avoid hot tubs
- Take a multivitamin that includes vitamin C, zinc, and folic acid
- Don’t take prescription drugs unless necessary
- Don’t take any illegal drugs
- Reduce alcohol and caffeine, and eliminate cigarettes
- Eat fruits and vegetables rich in antioxidants such as blueberries and avocados
- Eat Brazil nuts, which contain selenium, an antioxidant that improves sperm quality. WARNING: Too much selenium is toxic. Watch your intake.
- Reduce stress
- Exercise regularly, but use caution with long-distance cycling and contact sports
- Maintain a healthy weight
- Ejaculate frequently, but abstain two or three days before fertility treatment cycles
- Avoid lubricants
- Avoid environmental and workplace toxins: heavy metals, chemicals, and pesticides
Treatment Options for Male Infertility
Treating a man with a low sperm count can be difficult, especially if no further lifestyle factors can be modified. If the cause of the problem is a hormone imbalance (this is the case for about 1 in 100 of infertile men), then hormonal therapy may be appropriate.
Hormone imbalances that directly affect the development of the sperm can be successfully treated with injections of hormones called gonadotropins. Usually, the testes respond by producing normal amounts of testosterone, and sperm production will resume, although it can take several months of treatment to see any improvement.
Surgery may be the answer when there are anatomical problems causing male infertility such as obstructions or physical abnormalities such as a varicocele, a varicose vein in the testicles.
Several medications and recreational drugs have been shown to affect a man’s fertility and so check all mediation with your doctor to make sure it's not interfering with your sperm production.