Approximately 15% of couples are unable to conceive after one year of unprotected intercourse. A male factor is solely responsible in about 20% of infertile couples and contributory in another 30-40%. If a male infertility factor is present, it is almost always defined by the finding of an abnormal semen analysis, although other male factors may play a role even when the semen analysis is normal.
Components of evaluation for male infertility
The minimum full evaluation for male infertility for every patient should include a complete medical history, physical examination by a urologist and at least two semen analyses.
Medical history
- A complete medical and surgical history including chronic diseases, surgeries since childhood, trauma.
- Review of medications (prescription and non- prescription) and allergies.
- Lifestyle exposures like smoking, alcohol, recreational drugs.
- Family reproductive history.
- A survey of past infections such as sexually transmitted diseases and respiratory infections.
Physical examination
- A general physical examination.
- Secondary sexual characteristics including body habitus, hair distribution and breast development.
- Examination of male genital system for testicular size, epididymis, vas, location of urethral opening, presence of infections or any swellings.
Semen analysis
Semen analysis is the cornerstone of the laboratory evaluation of the infertile male and helps to define the severity of the male factor. Normal Semen parameters according to recent WHO criteria are listed below:
| Semen Analysis Parameter | Normal Values |
|---|---|
|
Volume |
1.5 ml or more |
|
pH |
> or equal to 7.2 |
|
Sperm concentration |
15,000,000/ml or more |
|
Total motility |
40% or more |
|
Progressive motility |
32% or more |
|
Morphology |
4% or more normal forms (Strict criteria) |
|
Vitality |
58% or more live |
|
White blood cells |
Less than 1,000,000/ml |
Semen analysis is performed with an abstinence of 3 to 5 days on two occasions. Usually if above tests are normal, no further evaluation is required. Any abnormality of above tests, or in case of unexplained infertility or repeated treatment failures, further advanced tests are warranted.
Other procedures and tests for assessing male fertility
Endocrine evaluation
An initial endocrine evaluation should include at least a serum testosterone and FSH. It should be performed if there is
- An abnormally low sperm concentration, especially if less than 10 million/ml
- Impaired sexual function.
- Clinical findings suggestive of a specific endocrinopathy.
Other hormonal assays include LH, Inhibin B, prolactin, TSH, SHBG. All these tests may together help to determine cause of abnormal spermatogenesis or infertility.
Post-ejaculatory urinalysis
A post-ejaculatory urinalysis should be performed in patients with ejaculate volumes of less than 1 ml, except in patients with bilateral vasal agenesis or clinical signs of hypogonadism to rule out retrograde ejaculation of sperms into urinary bladder. Significant numbers of sperm must be found in the urine of patients with low ejaculate volume oligospermia in order to suggest the diagnosis of retrograde ejaculation.
Ultrasonography – Transrectal ultrasonography/ Scrotal ultrasonography
Transrectal ultrasonography is indicated in azoospermic patients with palpable vasa and low ejaculate volumes to determine if ejaculatory duct obstruction exists. Scrotal ultrasonography is indicated in those patients in whom physical examination of the scrotum is difficult or inadequate or in whom a testicular mass or small varicocele is suspected.
DNA Integrity / DNA Fragmentation Index (DFI)
This test is done in cases of repeated treatment failures or unexplained infertility. The results correlate fairly well with the potential of sperm from a given male to produce embryos that would be sufficiently “competent” to produce a live birth. Based on the level of DNA integrity, line of successful treatment can be suggested. Test interpretation is as follows:
- Less than or equal to 15 percent DFI: Excellent to Good fertility potential
- 15 percent to 25 percent DFI: Good to Fair fertility potential.
- Greater than 25 percent DFI: Fair to Poor fertility potential.
Computer-aided sperm analysis
Computer-aided sperm analysis (CASA) requires sophisticated instruments for quantitative assessment of sperm from a microscopic image or from videotape. CASA is most useful clinically for assessing sperm motility and motion parameters, such as velocity or speed and head movement, which some believe may be important factors in determining sperm fertility potential.
Antisperm antibody testing
Pregnancy rates may be reduced by antisperm antibodies (ASA) in the semen. Risk factors for ASA include ductal obstruction, prior genital infection, testicular trauma and prior genital surgeries, isolated low motility of sperms, unexplained infertility.
Sperm Viable tests
These assays determine whether non-motile sperms are viable by identifying which sperm have intact cell membranes.
Less commonly used specialized tests:
- Sperm penetration assay: to test the ability of sperm to undergo changes and fuse to egg
- Tests of sperm-cervical mucus interaction: to look for the presence of antibodies.
- Reactive oxygen species (ROS) levels: Increased ROS can cause infertility by affecting semen parameters
Testicular Biopsy
This is mostly done in cases of Azoospermia with normal hormone profile to know if there is spermatogenesis in testes.
Genetic screening /Karyotyping
Genetic abnormalities may cause infertility by affecting sperm production or sperm transport. The three most common genetic factors known to be related to male infertility are:
- Cystic fibrosis gene mutations associated with congenital absence of the vas deferens.
- Chromosomal abnormalities resulting in impaired testicular function.
- Y-chromosome microdeletions associated with isolated spermatogenic impairment.
A precise and detailed medical history, physical examination, semen analyses and complementary tests, as appropriate, are the key to obtaining a correct diagnosis and to determining the best treatment strategies.
