Men’s reproductive tracts are somewhat less complicated then women’s. However, there are still a number of conditions that can affect male fertility. Here is an overview of some of the more common problems affecting men and causing infertility
Medical Conditions Impacting Sperm Count and Mobility
Abnormal morphologyMorphology simply refers to size and shape. In order to swim accurately and quickly towards the egg awaiting fertilization (and thus beat out the competition), sperm must be correctly formed. Sometimes sperm are misshapen, making it impossible for them to do their job in reaching and penetrating the egg.
Low sperm countIn addition to being properly shaped, there must be ample sperm, else fertilization will not take place. A “normal” sperm count is in the neighborhood of 20 million sperm per milliliter of semen. Counts less than this (i.e. 10 million or less sperm/ml of semen) indicates low fertility. It is rare for the testicles to produce no sperm at all, but it can occur.
Undescended testicleWhen the testicles fail to descend from the abdomen down into the scrotal sac, sperm production may be negatively affected. This is because the scrotum is designed to keep the testicles (and their contents) at a temperature that favors fertility. When the testicles remain in the abdomen, the temperature of sperm can be too warm. Testicles normally descend from the abdomen into the scrotum during the process of fetal development.
Variocelevaricose veins that appear in the scrotum are known as varioceles. Varioceles affect sperm count by failing to allow normal cooling of the affected testicle.
Male hypogonadismDisorders affecting the testicles, the pituitary or the hypothalamus may have a deleterious effect on hormone production and secretion, including testosterone. Testosterone affects functioning of the testicles.
Some genetic syndromes cause abnormal development of the testicles. Klinefelter’s syndrome is one example: in this syndrome, instead of having one x and one y chromosome, males have two x chromosomes and one y chromosome. This may result in poor or absent sperm production and low levels of testosterone. Males with Klinefelter’s syndrome have other signs and symptoms as well.
InfectionVarious infections can adversely affect sperm production. For example, the Mumps viral infection can affect sperm production when boys contract the disease after puberty. STDs can cause scarring which can block sperm passage. Other infections, such as prostatitis (inflammation of the prostate gland), urethritis (inflammation of the urethra) and epididymitis (inflammation of the epididymis) can all affect sperm motility.
Idiopathic causesIn some cases, no cause for decreased sperm count can be found. Sometimes subtle changes affecting the y chromosome are discovered through genetic testing, but in many cases the cause is never determined.
Medical Conditions Affecting Sperm DeliveryThese can be thought of as “mechanical” issues: in other words, problems affecting the ability to deliver sperm through the penis and into the vagina.
Sexual problemsED (erectile dysfunction) and premature ejaculation can obviously impact fertility. Relationship or psychological issues can also negatively impact the male’s ability to perform sexually. In addition, many couples are unaware that certain products, such as lubricants, can be toxic to sperm.
In this condition, semen goes into the bladder during ejaculation, rather than exiting the penis. Several medical conditions, as well as medications, can cause this issue to occur.
Tube blockageSome men are born missing the vas deferens, which is the tube that transports sperm from the testicles to the opening at the tip of the penis. The epididymis (the portion of the testicle containing sperm) may be blocked. Ejaculatory ducts may also be blocked. This can be congenital or be caused by infection or scarring.
Lack of semenSemen is the fluid that contains sperm. In certain conditions, such as in spinal cord injuries, lack of semen may occur.
HypospadiasIn this condition, the urinary meatus (the opening at the tip of the penis through which urine reaches the outside of the body) is located on the underside of the penis. If hypospadias is not corrected surgically, this can lead to infertility due to the fact that sperm cannot reach the female cervix (sperm is not directed towards the cervix).
AntibodiesMen who have had a vasectomy and then have the procedure reversed sometimes find that their body produces antibodies against their sperm that weaken them. This occurs as the result of having surgically blocked the vas deferens and may result in the failure of the reversal procedure.
Cystic fibrosisMen who have this disease sometimes have a missing or blocked vas deferens.
CancerCancer affecting the testicles can alter sperm counts, as can treatments aimed at eradicating cancer, such as chemotherapy and radiation. Men undergoing such treatments often choose to bank sperm samples before beginning treatment.
Lifestyle Factors Affecting Fertility
Sometimes the reasons for male fertility problems have more to do with lifestyle. Some of these factors can be altered while others, such as age, cannot.
StressStress can affect hormone levels in the body. Prolonged and severe stress can be detrimental to sperm production. Infertility itself can be stressful, leading to a vicious cycle of stress.
A normal sperm count requires a healthy body and good nutrition. Lack of certain nutrients, including zinc, vitamin C, folate and selenium, have been associated with male infertility.
ObesityMore and more studies are linking obesity with infertility in both men and women. Obesity is defined as having a BMI (body mass index) >30.
Alcohol/DrugsBoth alcohol use and the use of certain substances such as marijuana have been shown to adversely affect sperm production and motility. Substance dependency can also lead to malnutrition, another risk factor for infertility. The use of anabolic steroids (performance enhancing drugs) can lead to shrinkage of the testicles and diminished sperm production.
AgeAs men age, fertility may decline. This is not a hard and fast rule for some men but, generally speaking, men who are older than 40 may be less fertile than younger men.
SmokingStudies have shown that men who smoke have lower sperm counts than non-smoking men.
Overheating of the testiclesMen who routinely enjoy saunas, hot tubs and hot baths may inadvertently lower their sperm count. Men who wear tight-fitting clothing may experience the same.
There are many medical conditions that can lead to fertility problems in men. Many of these conditions can be treated, while others are not amenable to treatment. Discovering the root of the problem may require various tests and a visit to a specialist.