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| Evaluation of the cause of Infertility |
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The natural mechanism for conception is quite simple. The woman ovulates every month to produce an egg which travels up the fallopian tubes towards the uterus. Following intercourse, the sperms swim up the cervix into the uterus and travel down the fallopian tubes. The sperms and the egg meet for fertilisation to occur. The fertilized egg then travels to the uterus for implantation.
Infertility is defined as the inability to conceive after one year of regular unprotected sexual intercourse. A couple will experience difficulty with conception if one of the four systems described above is not functioning.
TIMING OF INTERCOURSE
Couples are generally advised to time intercourse with ovulation but in our experience, this causes a lot of stress which works against the process of conception. There is good evidence that couples that have intercourse two to three times a week have the same chance of conception as couples timing intercourse with ovulation.
ARE THE SPERMS CAPABLE OF FERTILISING THE EGGS?
This is usually done with the semen analysis with the semen assessed according to the world health organisation (WHO) criteria:
The semen analysis provides some ideal of the semen quality but it is quite difficult to make absolute predictions about a man's fertility based solely on the semen analysis because the man's fertility is expressed by the woman who is the one that gets pregnant. The woman can either compensate or exacerbate any inherent defects in the man's semen. Furthermore, the sperm density changes from day to day and serial assessment may need to be done to get a clear idea of a mans fertility potential.
An interesting concept in the expression of semen quality is the total normal motile count (TNMC) which is the active component of the semen according to WHO standards. This approximates at 1.5 million. There is evidence that approximately 15% of the TNMC gets into the fallopian tubes where fertilisation is said to occur. This approximates at 225,000 sperms and we know from our experience with IVF that we need about 200,000 normal motile sperms around the egg to achieve fertilisation in the laboratory. This analysis should help us understand the importance of the semen analysis in determining male infertility.
ARE THE FALLOPIAN TUBES OPEN?
The patency of the fallopian tubes are necessary to ensure the union of the sperm and the egg. There are many methods used to determine the patency (whether they are open or not) of the Fallopian tubes:
Hysterosalpingogram
This is a special x-ray test in which contrast is injected into the uterus through the cervix. The passage of the dye through the tubes is determined by the X-ray. The tubes are deemed open if the dye flows out of the tubes. This test suffers from a few limitations such as the fact that the egress of the dye through the tubes may be disrupted by spasm rather than blockage. Furthermore, it is not usually possible to define the cause of any abnormality defined by the X-ray.
Laparoscopy
This is a special telescopic examination where a telescope attached to a camera is inserted into the abdomen to allow direct confirmation of the passage of the dye through the fallopian tubes. It is generally regarded as a second line assessment of the fallopian tubes where the HSG has defined an abnormality. This test was very common in the days when corrective surgery on the fallopian tubes was popular because it allowed assessment of the extent of the damage to the tubes and the suitability for corrective surgery. The significant improvements that have been seen in the results of IVF treatment over the years has lead to a situation where tubal surgery is becoming obsolete as a method of treating tubal infertility. This means that the use of laparoscopy as a tool for assessing the fallopian tubes is quite limited now as the risks of the procedure which is done under general anesthesia far outweighs the benefits especially as most doctors will still recommend IVF whatever the results of the tubal surgery.
Other methods
There are other methods of assessing the fallopian tubes such as contrast sonography or hycosy but they all fall under the same arguments as discussed under laparoscopy.
Falloposcopy
The transport of the egg along the fallopian tubes depends on the integrity of the hair like processes called cilia that are necessary to "waft" the egg along the tube and it is possible to damage the cilia and still have patent tubes on HSG. This means that a tubal problem could still be the cause of infertility even though the woman has a normal HSG. Other techniques such as falloposcopy which involves inserting a small telescope into the fallopian tubes to visualise the integrity of the tubes. This is achieved by visualising the entrance of the tubes into the uterus during hysteroscopy. This technique is interesting but has limited practical application.
IS THE UTERUS IN A GOOD CONDITION
This is done by ultrasound scanning to define the presence of fibroids and the integrity of the endometrial cavity. Where necessary other tests such as fluid contrast sonograpy or hysteroscopy could be done to assist in the assessment of the cavity of the uterus looking for fibroids, polyps or adhesions.
Fibroids and polyps
Fibroids are benign tumours of the muscle of the uterus. They are extremely common in black women and as such a very determinant of outcome following assisted conception treatment. It is thought that women with fibroids of a certain size (5cm) in certain locations (within the cavity)
Adhesions
Adhesions are scar tissues that develop following inflammatory processes and
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