Low sperm count means that the fluid (semen) you ejaculate during an orgasm contains fewer sperm than normal. A low sperm count is also called oligospermia (ol-ih-go-SPUR-me-uh). A complete absence of sperm is called azoospermia. Your sperm count is considered lower than normal if you have fewer than 15 million sperm per milliliter of semen.
Having a low sperm count decreases the odds that one of your sperm will fertilize your partner's egg, resulting in pregnancy. Nonetheless, many men who have a low sperm count are still able to father a child.
The main sign of low sperm count is the inability to conceive a child. There may be no other obvious signs or symptoms. In some cases, an underlying problem such as an inherited hormonal imbalance, dilated testicular veins or a condition that blocks the passage of sperm may cause signs and symptoms. Low sperm count symptoms may include:
- Problems with sexual function — for example, low sex drive or difficulty maintaining an erection (erectile dysfunction)
- Pain, swelling or a lump in the testicle area
- Decreased facial or body hair or other signs of a chromosome or hormone abnormality
When to see a doctor
See a doctor if you:
- Are unable to conceive a child after a year of regular, unprotected sexual intercourse with your partner
- Have erection or ejaculation problems, low sex drive or other problems with sexual function
- Have pain, discomfort, a lump or swelling in the testicular area
- Have a history of testicle, prostate or sexual problems
- Have had groin, testicle, penis or scrotum surgery
The production of sperm is a complex process and requires normal functioning of the testicles (testes) as well as the hypothalamus and pituitary glands — organs in your brain that produce hormones that trigger sperm production. Once sperm are produced in the testicles, delicate tubes transport them until they mix with semen and are ejaculated out of the penis. Problems with any of these systems can affect sperm production. Also, there may be problems of abnormal sperm shape (morphology), movement (motility) or function. Often the cause of low sperm count isn't ever identified.
Low sperm count can be caused by a number of health issues and medical treatments. Some of these include:
- Varicocele. A varicocele (VAR-ih-koe-seel) is a swelling of the veins that drain the testicle. It's a common cause of male infertility. This may prevent normal cooling of the testicle, leading to reduced sperm count and fewer moving sperm. The treatment of a varicocele often improves sperm quality and overall fertility.
- Infection. Some infections can interfere with sperm production and sperm health or can cause scarring that blocks the passage of sperm. These include some sexually transmitted infections, such as chlamydia and gonorrhea; inflammation of the prostate (prostatitis); inflamed testicles; and other infections of the urinary tract or reproductive organs.
- Ejaculation problems. Retrograde ejaculation occurs when semen enters the bladder during orgasm instead of emerging out of the tip of the penis. Various health conditions can cause retrograde ejaculation, including diabetes, spinal injuries, and surgery of the bladder, prostate or urethra. Certain medications also may result in retrograde ejaculation, such as blood pressure medications known as alpha blockers. Some men with spinal cord injuries or certain diseases can't ejaculate semen at all, though they still can produce sperm.
- Antibodies that attack sperm. Anti-sperm antibodies are immune system cells that mistakenly identify sperm as harmful invaders and attempt to destroy them.
- Tumors. Cancers and nonmalignant tumors can affect the male reproductive organs directly, or can affect the glands that release hormones related to reproduction (such as the pituitary gland). Surgery, radiation or chemotherapy to treat tumors can also affect male fertility.
- Undescended testicles. During fetal development one or both testicles sometimes fail to descend from the abdomen into the sac that normally contains the testicles (scrotum). Decreased fertility is more likely in men with this condition.
- Hormone imbalances. The hypothalamus, pituitary and testicles produce hormones that are necessary to create sperm. Alterations in these hormones, as well as from other systems such as the thyroid and adrenal, may impair sperm production.
- Sperm duct defects. The tubes that carry sperm can be damaged by illness or injury. Some men are born with a blockage in the part of the testicle that stores sperm (epididymis) or a blockage of one of the tubes that carry sperm out of the testicles (vas deferens). Men with cystic fibrosis and some other inherited conditions may be born without sperm ducts altogether.
- Chromosome defects. Inherited disorders such as Klinefelter's syndrome — in which a male is born with two X chromosomes and one Y chromosome instead of one X and one Y — cause abnormal development of the male reproductive organs. Other genetic syndromes associated with infertility include cystic fibrosis, Kallmann's syndrome and Kartagener syndrome.
- Celiac disease. A digestive disorder caused by sensitivity to gluten, celiac disease can cause male infertility. Fertility may improve after adopting a gluten-free diet.
- Certain medications. Testosterone replacement therapy, long-term anabolic steroid use, cancer medications (chemotherapy), certain antifungal and antibiotic medications, some ulcer medications and some other medications can impair sperm production and decrease male fertility.
Overexposure to certain environmental elements can affect sperm production or function. Specific causes include:
- Industrial chemicals. Extended exposure to benzenes, toluene, xylene, herbicides, pesticides, organic solvents, painting materials and lead may contribute to low sperm counts.
- Heavy metal exposure. Exposure to lead or other heavy metals also may cause infertility.
- Radiation or X-rays. Exposure to radiation can reduce sperm production. It can take several years for sperm production to return to normal. With high doses of radiation, sperm production can be permanently reduced.
- Overheating the testicles. Frequent use of saunas or hot tubs may temporarily lower your sperm count. Sitting for long periods, wearing tight clothing or using a laptop on your lap for long periods of time also may increase the temperature in your scrotum and reduce sperm production. The type of underwear you choose to wear is unlikely to significantly impact your sperm count.
- Prolonged bicycling. Prolonged bicycling is another possible cause of reduced fertility due to overheating the testicles.
Health, lifestyle and other causes
Other causes of low sperm count include:
- Illegal drug use. Anabolic steroids taken to stimulate muscle strength and growth can cause the testicles to shrink and sperm production to decrease. Use of cocaine or marijuana may temporarily reduce the number and quality of your sperm as well.
- Alcohol use. Drinking alcohol can lower testosterone levels and cause decreased sperm production.
- Occupation. Certain occupations may increase your risk of infertility, including those associated with extended use of computers or video display monitors, shift work and work-related stress.
- Tobacco smoking. Men who smoke may have a lower sperm count than do those who don't smoke.
- Emotional stress. Severe or prolonged emotional stress, including stress about fertility itself, may interfere with certain hormones needed to produce sperm.
- Weight. Obesity can cause hormone changes that reduce male fertility.
- Sperm testing issues. Lower than normal sperm counts can result from testing a sperm sample that was taken too soon after your last ejaculation; was taken too soon after an illness or stressful event; or didn't contain all of the semen you ejaculated because some was spilled during collection. For this reason, results are generally based on several samples taken over a period of time.
A number of risk factors are linked to low sperm count and other problems that can cause low sperm count. They include:
- Smoking tobacco
- Drinking alcohol
- Using certain illegal drugs
- Being overweight
- Having certain past or present infections
- Being exposed to toxins
- Overheating the testicles
- Having a prior vasectomy or vasectomy reversal
- Being born with a fertility disorder or having a blood relative with a fertility disorder
- Having certain medical conditions, including tumors and chronic illnesses
- Undergoing cancer treatments, such as surgery or radiation
- Taking certain medications
- Performing prolonged activities such as bicycling or horseback riding, especially on a hard seat or poorly adjusted bicycle
Infertility caused by low sperm count can be stressful for both you and your partner. Complications can include:
- Surgery or other treatments for an underlying cause of low sperm count
- Expensive and involved assisted reproductive techniques, such as in vitro fertilization
- Stress related to the inability to have a child
You should start with your family doctor or a general practitioner. However, he or she may well refer you to an infertility specialist.
Here's some information to help you get ready for your appointment, and what to expect from your doctor.
What you can do
- Be aware of any pre-appointment restrictions. At the time you make the appointment, be sure to ask if there's anything you need to do in advance, such as refraining from ejaculating for a certain period of time or stopping certain medications.
- Write down any symptoms you're experiencing, including any that may seem unrelated to the reason for which you scheduled the appointment.
- Write down key personal information, including any major stresses or recent life changes.
- Find out whether you have a family history of fertility problems. Having a male blood relative, such as your brother or father, with fertility problems or other reproductive issues may give clues to the cause of low sperm count.
- Make a list of all medications, vitamins and supplements that you're taking.
- Take your partner along. Even if you have a low sperm count, your partner also may need tests to see whether she has any problems that could be preventing pregnancy. It's also good to have your partner along to help keep track of any instructions your doctor gives you or to ask questions you may not think of.
- Write down questions to ask your doctor.
Some basic questions to ask your doctor include:
- What do you suspect may be causing my low sperm count?
- Other than the most likely cause, what are other possible reasons my partner and I haven't been able to conceive a child?
- What kinds of tests do I need?
- Will my partner also need tests?
- What treatments are available to increase my sperm count? Which do you recommend?
- Are there any restrictions that I need to follow?
- At what point should we consider other alternatives, such as a sperm donor or adoption?
- Are there any brochures or other printed material that I can take home with me? What websites do you recommend visiting?
Don't hesitate to ask additional questions during your appointment.
What to expect from your doctor
Some questions your doctor may ask you include:
- At what age did you start puberty?
- Have you had a vasectomy or a vasectomy reversal?
- Do you use illegal drugs, such as marijuana, cocaine or anabolic steroids?
- Have you been exposed to toxins such as chemicals, pesticides, radiation or lead, especially on a regular basis?
- Are you currently taking any medications, including dietary supplements?
- Do you regularly take hot baths or steam baths?
When you see a doctor because you're having trouble getting your partner pregnant, he or she will try to determine the underlying cause. Even if your doctor thinks low sperm count is the problem, you and your partner may both need tests to rule out other causes of infertility and to look for any underlying health problems. Testing and diagnosis may involve the following:
General physical examination and medical history
This includes examination of your genitals and questions about any inherited conditions, chronic health problems, illnesses, injuries or surgeries that could affect fertility. Your doctor may also ask about your sexual habits and your sexual development.
A low sperm count is diagnosed as part of a semen analysis test. Sperm count is generally determined by examining semen under a microscope to see how many sperm appear within squares on a grid pattern. In some cases, a computer may be used to measure sperm count.
To collect a semen sample, your doctor will have you masturbate and ejaculate into a special container. It's also possible to collect sperm for examination during intercourse, using a special condom. Sperm counts often fluctuate. In most cases, several semen analysis tests are done over a period of time to ensure accurate results.
New sperm are produced continually in the testicles and take about 40 to 76 days to mature. So, a current semen analysis reflects your environment over the past 2.5 months. Any positive changes you've made won't show up for a period of several months.
One of the most common causes of low sperm count is incomplete or improper collection of a sperm sample. Most doctors will check two or more semen samples over time to ensure consistency between samples. To ensure accuracy in a collection, your doctor will want to:
- Ensure all of your semen makes it into the collection cup or collection condom when you ejaculate
- Wait at least three months after you've recovered from an illness or stressful event to collect a sperm sample
- Have you abstain from ejaculating for at least two but no longer than seven days before collecting a sample
- Make sure a second sample is collected at least seven days after the first
- Have you avoid the use of lubricants because these products can affect sperm motility
Semen analysis results
Normal sperm densities range from 15 million to greater than 200 million sperm per milliliter of semen. You are considered to have a low sperm count if you have fewer than 15 million sperm per milliliter or less than 39 million sperm total per ejaculate. Your chance of getting your partner pregnant decreases with decreasing sperm counts. Some men have no sperm in their semen at all. This is known as azoospermia (ay-zoh-uh-SPUR-me-uh).
There are many factors involved in reproduction, and the number of sperm in your semen is only one. Some men with low sperm counts successfully father children. Likewise, some men with normal sperm counts are unable to father children. Even if you have enough sperm, you're much more likely to get your partner pregnant if at least half of your sperm have normal forward movement (motility).
Depending on initial findings, your doctor may recommend additional tests to look for the cause of your low sperm count and other possible causes of male infertility. These can include:
- Scrotal ultrasound. This test uses high-frequency sound waves to look at the testicles and supporting structures.
- Transrectal ultrasound. A small lubricated wand is inserted into your rectum to check your prostate, and for blockages of the tubes that carry semen (ejaculatory ducts and seminal vesicles).
- Hormone testing. Your doctor may recommend a blood test to determine the level of hormones produced by the pituitary, hypothalamus and testicles, which play a key role in sexual development and sperm production.
- Post-ejaculation urinalysis. Sperm in your urine can indicate your sperm are traveling backward into the bladder instead of out your penis during ejaculation (retrograde ejaculation).
- Genetic tests. When sperm concentration is extremely low, genetic causes could be involved. A blood test can reveal whether there are subtle changes in the Y chromosome — signs of a genetic abnormality. Genetic testing may also be ordered to diagnose various congenital or inherited syndromes.
- Testicular biopsy. This test involves removing samples from the testicle. It may be used if your semen analysis shows no sperm at all. The results of the testicular biopsy will tell if sperm production is normal. If it is, your problem may be caused by a blockage or another problem with sperm transport.
- Anti-sperm antibody tests. These tests are used to check for immune cells (antibodies) that attack sperm and affect their ability to function.
- Specialized sperm function tests. A number of tests can be used to evaluate how well your sperm survive after ejaculation, how well they can penetrate an egg and whether there's any problem attaching to the egg. If you do have a low sperm count, having healthy sperm can be an important factor in male fertility.
Treatments for low sperm count include:
- Surgery. For example, a swelling of the veins that drain the testicle (varicocele) can often be surgically fixed or an obstructed vas deferens tube repaired.
- Treating infections. Antibiotics can cure an infection of the reproductive tract, but this doesn't always restore fertility.
- Hormone treatments and medications. Hormone replacement or medications may be prescribed to change hormone levels. It can take between three and six months before you'll notice any effects on your semen analysis.
- Assisted reproductive technology (ART). ART treatments involve obtaining sperm through normal ejaculation, surgical extraction or from donor individuals, depending on your specific case and wishes. The sperm is then inserted into the female genital tract, or used for in vitro fertilization or intracytoplasmic sperm injection.
When treatment doesn't work
Sometimes male fertility problems can't be treated, and it's impossible for a man to father a child. If this is the case, you and your partner can consider either using sperm from a donor or adopting a child.
There are a few steps you can take at home to increase your chances of getting your partner pregnant:
- Increase frequency of sex. Having sexual intercourse every other day around the time of ovulation increases your chances of getting your partner pregnant.
- Have sex when fertilization is possible. A woman is likely to become pregnant during ovulation — which occurs around the middle of the menstrual cycle, between periods. Experts generally recommend having intercourse every two days near the time of ovulation. This will ensure that sperm, which can live several days, are present when conception is possible.
- Avoid the use of lubricants. Some products such as Astroglide or K-Y jelly, lotions, and saliva have been shown to reduce sperm movement. Ask your doctor about sperm-safe lubricants.
Evidence is still limited on whether — or how much — herbs or supplements might help increase sperm count or overall sperm health.
Although there is no conclusive information on the benefit of dietary supplementation, certain vitamins, minerals and amino-acids may improve sperm count or sperm quality. They include:
- Alpha-lipoic acid
- L-acetyl carnitine
- Co-enzyme Q10
- Ethyl cysteine
- Folic acid
- N-acetyl cysteine
- Polyunsaturated fatty acids
- Vitamins A, C, D and E
Talk to your doctor before taking any herbal remedies or supplements, as some can cause harm when taken in high doses (megadoses) or for extended periods of time.
You should avoid some known factors that can affect sperm count and quality:
- Don't smoke.
- Limit or abstain from alcohol.
- Steer clear of illegal drugs.
- Talk to your doctor about medications that can affect sperm count.
- Keep the weight off.
- Avoid the heat.
- Reduce stress.
- Avoid pesticides, heavy metals and other toxins.
June 12, 2014
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