Azoospermia is a condition that affects male fertility. It means that there is no sperm in the semen, which makes it impossible to conceive naturally. Azoospermia can have different causes and treatments depending on the type and severity of the condition. In this article, we will explain what azoospermia is, what are its types, common causes, diagnostic tests, treatment options, the role of lifestyle changes, fertility preservation, emotional impact, prevention tips, and the overall outlook for individuals diagnosed with this condition.
What is azoospermia?
Sperm is produced in the testicles and travels through the reproductive tract to mix with the fluid from the seminal vesicles and the prostate gland. This mixture forms the semen, which is ejaculated through the penis during orgasm. A normal sperm count is considered to be 15 million per milliliter (mL) or more. Men with low sperm count (oligozoospermia) have less than 15 million sperm per mL. Men with azoospermia have no measurable sperm in their semen.
Azoospermia affects about 1% of all men and 10% to 15% of infertile men. It can be a cause of male infertility, but it does not mean that a man cannot father a child. Depending on the type and cause of azoospermia, there may be ways to treat it or to retrieve sperm for assisted reproductive techniques (ART).
What are the types of azoospermia?
There are two main types of azoospermia:
Obstructive and non-obstructive.
Obstructive azoospermia.
Obstructive azoospermia means that there is a blockage or a missing connection in the reproductive tract that prevents the sperm from reaching the semen. The blockage can occur in the epididymis (the coiled tube behind the testicles where sperm mature), the vas deferens (the tube that carries sperm from the epididymis to the ejaculatory duct), the ejaculatory duct (the tube that connects the vas deferens to the urethra), or the urethra (the tube that runs through the penis and carries urine and semen).
Obstructive azoospermia can be caused by:
- Congenital defects, such as missing or abnormal parts of the reproductive tract
- Infections, such as sexually transmitted infections (STIs), epididymitis, or prostatitis
- Injuries or surgeries, such as vasectomy, hernia repair, or pelvic trauma
- Scarring or inflammation, such as from tuberculosis or schistosomiasis
Obstructive
azoospermia can affect one or both sides of the reproductive tract. If only one
side is affected, some sperm may still be present in the semen, but in low
amounts. If both sides are affected, no sperm will be found in the semen.
Non-obstructive azoospermia means that there is no blockage in the reproductive tract, but there is a problem with the production or maturation of sperm in the testicles. The testicles may not produce enough sperm, produce abnormal sperm, or produce no sperm at all.
Non-obstructive azoospermia can be caused by:
- Genetic disorders, such as Klinefelter syndrome (an extra X chromosome), Y chromosome microdeletions (missing parts of the Y chromosome), or cystic fibrosis (a disease that affects mucus production)
- Hormonal imbalances, such as low levels of testosterone, follicle-stimulating hormone (FSH), luteinizing hormone (LH), or thyroid hormones
- Medications or treatments, such as chemotherapy, radiation therapy, steroids, or anti-androgens
- Lifestyle factors, such as smoking, alcohol abuse, drug abuse, obesity, stress, or exposure to toxins
- Testicular conditions, such as undescended testicles (cryptorchidism), varicocele (enlarged veins in the scrotum), testicular torsion (twisting of the testicle), testicular cancer, or testicular atrophy (shrinking of the testicles)
Non-obstructive azoospermia can affect one or both testicles. If only one testicle is affected, some sperm may still be produced by the other testicle and reach the semen. If both testicles are affected, no sperm will be produced at all.
What are the common causes of azoospermia?
The most common causes of azoospermia vary depending on the type of azoospermia. For obstructive azoospermia, the most common causes are:
- Vasectomy, a surgical procedure that cuts or ties the vas deferens to prevent sperm from reaching the semen
- Congenital absence of the vas deferens (CAVD), a condition that is present at birth and results in missing or abnormal vas deferens
- Infections, such as chlamydia, gonorrhea, or tuberculosis, that can cause inflammation and scarring of the reproductive tract
For non-obstructive azoospermia, the most common causes are:
- Klinefelter syndrome, a genetic disorder that affects about 1 in 500 to 1 in 1000 men and causes an extra X chromosome, which can impair sperm production and testosterone levels
- Y chromosome microdeletions, a genetic disorder that affects about 5% to 10% of men with non-obstructive azoospermia and causes missing parts of the Y chromosome, which can affect sperm production and quality
- Varicocele, a condition that affects about 15% of men and causes enlarged veins in the scrotum, which can increase the temperature and reduce the blood flow to the testicles, affecting sperm production and quality
How is azoospermia diagnosed?
Azoospermia is diagnosed by a semen analysis, a test that measures the quantity and quality of sperm in the semen. A semen analysis requires a sample of ejaculate that is collected by masturbation or by using a special condom during intercourse. The sample is then examined under a microscope to count and evaluate the sperm.
A normal semen analysis should have at least 15 million sperm per mL and at least 40% of them should be moving (motile). A low sperm count (oligozoospermia) is defined as less than 15 million sperm per mL. A zero sperm count (azoospermia) is defined as no sperm in the semen.
A single semen analysis is not enough to diagnose azoospermia. Sometimes, sperm may be absent in one sample but present in another due to various factors, such as stress, illness, medication, or ejaculation frequency. Therefore, at least two semen analyses are needed to confirm azoospermia. The samples should be collected at least one week apart and after two to five days of abstinence from ejaculation.
If azoospermia is confirmed by two semen analyses, further tests are needed to determine the type and cause of azoospermia. These tests may include:
- Physical examination, to check for any abnormalities in the genitals, such as undescended testicles, varicocele, or signs of infection
- Hormone tests, to measure the levels of testosterone, FSH, LH, prolactin, and thyroid hormones in the blood
- Genetic tests, to check for any chromosomal abnormalities or gene mutations that may affect sperm production or quality
- Scrotal ultrasound, to look for any blockages or structural problems in the testicles or epididymis
- Transrectal ultrasound, to look for any blockages or structural problems in the prostate or ejaculatory ducts
- Vasography, to inject a dye into the vas deferens and take an X-ray to see if there is any obstruction or leakage
- Testicular biopsy, to take a small sample of tissue from the testicle and examine it under a microscope to see if there is any sperm production or maturation
How is azoospermia treated?
The treatment of azoospermia depends on the type and cause of the condition. The main goals of treatment are to restore sperm production or delivery, improve fertility potential, and address any underlying health issues.
Treatment for obstructive azoospermia
For obstructive azoospermia, the treatment options are:
- Surgery, to repair or bypass any blockages or missing connections in the reproductive tract. For example, vasovasostomy (reconnecting the vas deferens), vasoepididymostomy (connecting the vas deferens to the epididymis), or epididymovasostomy (connecting the epididymis to another part of the epididymis)
- Sperm retrieval, to collect sperm directly from the testicle or epididymis using a needle or a small incision. The retrieved sperm can then be used for ART, such as intrauterine insemination (IUI) or in vitro fertilization (IVF) with intracytoplasmic sperm injection (ICSI)
- Sperm donation, to use donor sperm for ART if surgery or sperm retrieval are not possible or successful.
Treatment for non-obstructive azoospermia
For non-obstructive azoospermia, the treatment options are:
- Hormone therapy, to correct any hormonal imbalances that may affect sperm production or quality. For example.