LOW SPERM COUNT
Low sperm count is typically identified by a semen analysis. It is calculated by multiplying the volume (cc) of the semen by the concentration (million sperm/cc) by the motility (% moving). Normal sperm count is more than 40 million motile sperm in the ejaculate. Fewer than 40 million may cause conception difficulties.
There are a number of things that can cause low sperm count and a number of things that can help increase sperm count.
Causes
Varicoceles are dilated veins in the scrotum (just as an individual may have varicose veins in their legs). These veins are dilated because the blood does not drain properly from them. These dilated veins allow extra blood to pool in the scrotum, which has a negative effect on the sperm production. This condition is the most common reversible cause of male factor infertility and may be corrected by minor outpatient surgery.
Most experts do this microscopically to preserve the arterial supply and lymphatics. A sub-inguinal incision (about 1 inch above the penis and 1 inch from the midline) is usually used, as this avoids incising the abdominal muscles and creates less post-operative pain.
If the seminal fluid is very thick, it may be difficult for the sperm to move through it and into the woman's reproductive tract. Often, the semen can be processed to separate the moving sperm from the surrounding debris, dead sperm, and seminal fluid. The processed sperm is usually placed directly inside the uterus with a small tube (catheter). This is called intrauterine insemination (IUI).
A patient may have bilateral (both sides) congenital (from birth) absence of the vas deferens. He may have obstructions either at the level of the epididymis (the delicate tubular structure draining the testes) or higher up in the more muscular vas deferens. He may have become mechanically blocked during hernia or hydrocele repairs. He may have become blocked by scar tissue as a response to an infection.
Sperm are stored in sacs called the seminal vesicles and are then deposited in the urethra, which is the tube through which men urinate and ejaculate. The sperm must pass through the ejaculatory ducts to get from the seminal vesicles to the urethra. If these are blocked on both sides, no sperm will come through.
In some situations, the ducts may be repaired or unblocked to allow sperm to flow through the man's reproductive tract. If this is not possible, the sperm may be harvested to allow them to flow through the man's reproductive tract. Because they are obtained in lower numbers, they must be used in conjunction with advanced reproductive techniques to attempt a pregnancy.
Men can develop an immunologic response (antibodies) to their own sperm. The causes for this may include testicular trauma, testicular infection, large varicoceles or testicular surgery. Sometimes, there are unexplained reasons why this occurs.
These antibodies have a negative effect on fertility, although the exact reason why this is the case is unclear. Most likely, these antibodies act negatively at several points along the pathway to fertilization. They make it more difficult for the sperm to penetrate the partner's cervical mucous and make its way into the uterus. They make it more difficult for the sperm to bind with the zonapellucida (the external membrane or shell of the egg). Also, the antibodies make it more difficult for the sperm to fuse with the membrane of the oocytes (eggs) themselves.
The treatment for anti-sperm antibodies is somewhat controversial. Men may be treated with corticosteroids. However, this can lead to significant morbidity in the man. The most significant is aseptic necrosis of the hip (noninfectious destruction of the joint), requiring hip replacement.
Most of the time, the first level of intervention includes intra-uterine inseminations. If the couple is planning in-vitro fertilization (IVF) the presence of anti-sperm antibodies is usually an indication to inject the sperm directly into the egg (ICSI) instead of conventional IVF.
This generally refers to the inability of the sperm-producing part of the testicle (the seminiferous epithelium) to make adequate numbers of mature sperm. This failure may occur at any stage in sperm production for a number of reasons. The testicle may completely lack the cells that divide to become sperm (“Sertoli Cell-Only syndrome”). There may be an inability of the sperm to complete their development ("maturation arrest"). Sperm may be made in such low numbers that few, if any, successfully travel through the ducts and into the ejaculated fluid (hypospermatogeneses). This situation may be caused by genetic abnormalities, hormonal factors, or varicoceles.
Even in the case where the testes are only producing low numbers of sperm, the sperm may be harvested and used in conjunction with advanced reproductive techniques to attempt a pregnancy.
There are a number of fairly common drugs, which may have a negative effect on sperm production and/or function. They include:
- Ketoconazole (an anti-fungal)
- Sulfasalazine (for inflammatory bowel disease)
- Spironolactone (an anti-hypertensive)
- Calcium Channel Blockers (anti- hypertensives)
- Allopurinol, Colchicine (for gout)
- Antibiotics: Nitrofuran, Erythromycin, Gentamicin
- Methotrexate (cancer, psoriasis, arthritis)
- Cimetidine (for ulcers or reflux)
The testicles need pituitary hormones to be stimulated to make sperm. If these are absent or severely decreased, the testes will not maximally produce sperm. Importantly, men who take androgens (steroids) for body building, either by mouth or injection, shut down the production of hormones for sperm production.
A hormonal profile must be performed on all men with male factor infertility. This will help rule out serious medical conditions, give more information on the sperm-producing ability of the testes, and may reveal situations where hormonal treatment is indicated.
Men may have infections of their reproductive tract. These may include infections of the prostate (prostatitis), of the epididymis (epididymitis), or of the testis (orchitis).
Post-pubertal viral infections of the testes may cause significant damage (atrophy) of the testes and may cause absolute and irreversible infertility. Bacterial infections or sexually transmitted diseases may cause blockages at the sperm ducts. The patient may have normal production of sperm, but the ducts carrying it are obstructed.
Active bacterial or viral infections may have a negative effect on sperm production or sperm function. White blood cells, which are the body's response to infection, may also have a negative effect on sperm membranes, making them less hearty.
If excessive white blood cells or bacteria (more than 1 million/cc) are seen in a semen specimen, cultures should be done. This usually includes cultures for commonly asymptomatic, sexually-transmitted diseases including mycoplasma, ureaplasma and chlamydia. Also, a general genital culture is usually taken. If the infection and the white blood cells are persistent, then antibiotics may be considered.
It is important to note that, in most men, the ejaculate is not sterile. In controlled studies, the average man will culture positive for approximately two organisms. It is therefore very important to be judicious in the treatment of non-sexually-transmitted organisms found on cultures.
When these conditions are treated, a man will often see a significant improvement in his semen analysis.
Cigarette smoking has been shown to significantly affect semen quality.
Regular smoking causes a 23% decrease in sperm density (concentration) and a 13% decrease in motility (when averages are taken from nine separate studies). To a lesser extent, smoking causes an increased number of sperm with abnormal morphology (shape). Smoking causes toxicity to the seminal plasma (the fluid ejaculated with the sperm). Sperm from non-smokers were adversely affected (had significantly decreased viability) when placed in the seminal plasma (hormonal) of smokers.
Smoking effects the hypothalamic-pituitary-gonadtropin axis, most commonly affecting levels of estradiol and estrone (estrogens, which are hormones found in higher concentrations in women). The Leydig Cells, which are in the testes and produce testosterone, may have secretory dysfunction. Most worrisome is that there is evidence that suggests that paternal smoking may also be associated with congenital abnormalities and childhood cancer, though the relative risk in most studies is less than two.
Marijuana
Marijuana often causes a decreased average sperm count, motility, and normal morphology. It affects the hormonal axis (HPG), causing decreased plasma testosterone. It may also have a direct negative effect on the Leydig Cells.
Cocaine
Even infrequent cocaine use causes decreased sperm counts, motility and normal morphology. These effects can be found in men who have used cocaine in the two years preceding their initial semen analysis.
Cocaine also decreases the ability of sperm to penetrate cervical mucous, making it difficult for them to enter the uterus.
Anabolic Steroids (male hormones)
- The use of anabolic androgenic steroids has reached almost epidemic proportions. Nearly 7% of 12th grade males use or have used them to build muscle mass and improve athletic performance. These male hormones suppress the testes ability to make testosterone. This decreases the intratesticular testosterone level.
- Anabolic steroids depress testicular production of testosterone and thus, levels of testosterone inside the testes itself. This may cause severely diminished spermatogenesis or complete absence of sperm (azoospermia).
- When taken, these steroids cause a persistent depression of the hypothalamus and pituitary, which may be irreversible even when the steroids are stopped.
Alcohol
Moderate alcohol use does not affect male fertility. Excessive alcohol use affects the hormonal axis and is a direct gonadotoxin. It may cause associated liver dysfunction and nutritional deficiencies, which are also detrimental for sperm production.
Lubricants
Most vaginal lubricants, including K-Y Jelly, Surgilube, and Lubifax, are toxic to sperm. Couples should avoid their use during the fertile time of a woman's cycle.
Exercise
Moderate amounts of exercise can only be helpful. However, long distance runners (men who run greater than 100 miles per week) and distance cyclers (men who ride greater than 50 miles per week) have decreased spermatogenesis. These activities should be moderated when a sub-fertile man is attempting conception.
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Treatment
More than 50% of men will have a treatable cause of low sperm count. These factors include varicoceles (dilated veins in the scrotum), infections, hormonal abnormalities, abnormalities in the seminal fluid, ductal blockages, and difficulties with erections and ejaculation. When these conditions are treated, either through medication (hormones or antibiotics) or surgery (varicocelectomy, vasal reconstruction, repair of a blocked ejaculatory duct), a man will often see a significant improvement in his semen analysis.
Those men with poor semen analyses whose conditions are not treatable may still have the option of using advanced reproductive techniques to achieve a pregnancy. Even those men with no sperm in the ejaculate may be able to have some living sperm procured from them through other methods and achieve a pregnancy using advanced reproductive techniques. Those few men who produce absolutely no sperm at all will have this information so that they can explore other options.
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