Causes of infertility

Infertility is a couple's problem, and is commonly due to some contribution from both the male and female partners. Approximately 40% of the time, the male contributes a significant part of the fertility problem.

FEMALE CAUSES
Female infertility may be broken into several categories:

1. Ovulatory problems
2. Cervical factors
3. Pelvic and tubal factors, and
4. Uterine factors

Often, a combination of these problems exists.

Ovulation is a complex event in which hormonal signals and physical events are linked in a delicate balance. Women ovulate most effectively in their late teens and early twenties. By age 35-38, most women may experience a decline in the ability to ovulate effectively.

Ovulation can be seriously affected by:

1. Abnormalities of the thyroid gland
2. Overproduction of prolactin (a hormone leading to breast milk production)
3. Excessive male hormone (androgens)
4. Physical stress, psychological stress and extreme lifestyle changes

Cervical infertility involves inability of the sperm to pass through the mouth of the uterus due to damage of the cervix.
Causes include the following:

1. Inadequate or inhospitable cervical mucous
2. Cervical narrowing or "stenosis"
3. Infections of the cervix with common sexually transmitted diseases
    (chlamydia, gonorrhea, or trichomonas, as well as mycoplasma hominis and ureaplasma urealyticum)
4. Immune attack of sperm or "sperm allergy"

Pelvic causes include any disruption of the normal pelvic anatomy:

1. Scar tissue or "adhesions"
2. Endometriosis
3. Blocked, scarred, or distorted fallopian tubes
4. Benign tumors (fibroids) of the uterus

Uterine causes include:

1. Thin or abnormal uterine lining
2. Anatomic problems (polyps, uterine fibroids, abnormal shape of the uterus, septum or "dividing wall" within the     uterus)

Unexplained Infertility
Approximately 10% of infertile women suffer from unexplained infertility. This simply means that the commonly performed tests to diagnose the cause of infertility are all normal and do not define the reason for infertility. However, a more thorough search for a cause should be made, since many subtle abnormalities may be discovered to explain the infertility. Usually such problems are due to:

1. Difficulty in picking up the egg by fallopian tube
2. Failure of implantation of the embryo into the uterus
3. Failure of the sperm to fertilize the egg even when in contact.

MALE CAUSES
Low sperm counts, abnormal sperm morphology (shape), and low sperm motility are usually asymptomatic conditions to most males. Most cases of low sperm counts are "idiopathic" or unexplained. Some cases are associated with a swollen varicose vein in the scrotum, called a varicocele.

Some simple abnormalities may be improved by reducing stress, reducing heat to the genitals (e.g. avoidance of tight clothing, saunas or hot tubs), or by changing harmful lifestyle habits (avoiding tobacco, alcohol, or drugs such as marijuana). Short-term illnesses, significant stressful periods, and some medications may temporarily affect sperm counts.
The following causes of male infertility should be investigated:

1. Exposure to hazardous toxins, chemicals, or radiation 2. Infections such as mumps, or venereal diseases 3. Testicular injury (sports or work injury) 4. Childhood illness (failure of a testicle to descend properly) 5. Blockage of one of the ducts allowing flow of sperm from the testicle Injury, infection or prior vasectomy Genetic absence of these ducts (cystic fibrosis)
6. Immune reaction against sperm (antisperm antibodies) 7. Testicular failure and other hormonal problems 8. Chronic medical illness (thyroid disease, diabetes, and hypertension) 9. Spinal cord injuries and paralysis 10. Varicocele.