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Monday, February 16, 2015

The Human Sperm in Fertility

There is a need to relate sperm functions to the ability of a woman to reproduce.  It’s an  established the fact  that for fertilisation to occur, a female egg should come in contact with a sperm, which penetrates the egg and this results, in an embryo, which develops into a live baby at birth.
About 25% of all infertility is caused by a sperm defect, and 40% - 50% of infertility cases have a sperm defect as the main cause, or a contributing cause.  It is sometimes difficult to know whether the sperm problem is the only cause, or just a contributing cause to infertility.  Part of the problem is that too much emphasis is placed on numbers or statistics.
• Men with very low sperm counts can sometimes have children.
• Some men with normal sperm counts can be infertile.
The issue is not only how many or how fast they swim, but whether they can fertilize the female partner’s egg which is a biochemical issue.
It is also important to know that the severity of the sperm defect would indicate the actual treatment to be employed. Males with poor semen quality can be made to undergo
hormonal blood tests and appropriate medications given. Also that most sperm abnormalities are genetic and therefore not easy to treat, but work towards selecting the most motile and viable sperms for use in inseminations or IVF.
The sperm is the male sex cell, which is produced in the testes in the scrotum, and is released at ejaculation during intercourse or production for treatment.  A sperm cell is made up of an oval head, a midpiece and a tail.  These all have to be regular shape and size.
A normal semen parameter is >20  million  per ml with motility >50% and 2/4 progressive motion mostly normal shape, with normal viscosity, liquefies in 20 – 30mins after ejaculation.
The male factor infertility is defined as the abnormalities in the concentration of sperms present, the proportion of the motile and morphologically normal sperms.
It is important to note that semen analysis is not  a test for fertility, as this is determined
by various factors related to a couple to initiate a pregnancy.
Volume: A low semen volume may be an indication of retrograde ejaculation or absence or decrease of seminal vesicle component of ejaculate.  Seminal vesicle fluid is alkaline,  while prostate secretion is acidic.
A highly viscous semen may affect sperm motility.  Low sperm is Oligospermia - less than
<20 106.="" br="" nbsp="" style="margin: 0px; padding: 0px;" x="">Sperm concentration of less than 5m/ml is described as severe Oligospermia.
Absence of sperm is called Azospermia.  Normospermic semen contains >20x 106
Motility (movement).  The motility is normal if more than 50% at 1hour.  A forward progression is how fast a sperm moves and this should be >2/4 on a scale of 0 – 4.
0     -    no movement
1    -    movement , move forward
2    -    slow, undirected
3    -    fast , directed forward movement
4    -    extremely  fast forward movement
Morphology- this is the shape of the sperm cell, and could be classified as normal and oval shaped, tapered, amorphous, duplicated and immature.  A normal sperm is oval in shape, with smooth contours; no abnormalities in midpiece, and tail.  It is recommended that normal sperms morphology should be greater than 40%, for pregnancy to occur normally.
Semen samples with more than 1 x 106/ml white  blood cells is indicative of an infection.
Age: semen quality reduces as age increases, and the semen volume, sperm concentration, total sperm count, motility, total motile sperm, and morphology decrease as age increases.
Methods of semen preparation
The ideal sperm preparation technique aims to increase the capacity to accumulate a relatively large number of normal and viable sperms with good motility, in a small volume. 
The criteria for choosing a method for sperm preparation technique include:
• Semen volume
•Sperm morphology
* Sperm motility & count.
These techniques include:
•    Swim up
•    Swim down
•    Wash
•    Density gradient
SWIM UP – fairly normal, small volume
SWIM DOWN – poor morphology, low motility, high viscosity
WASH – normal morphology, highly viscous, large volume
DENSITY GRADIENT- Poor morphology – head, very small volume
Density gradient – this is for use on very poor semen samples, severe Oligospermia, and is the most effective method of achieving best quality sperms. A successful method would result in the improvement of the progressive sperm quality and a decrease in debris content after processing.  The ultimate aim is to select for the most motile, and viable sperm, that will eventually fertilize an egg for pregnancy to occur.
Artificial insemination
Artificial insemination is a process whereby sperm is introduced into the reproductive tract of the female (vaginal canal) or uterus, for the purpose of achieving a pregnancy.  This process is done using an insemination catheter. The sperm produced can either be from the husband (AIH) or from a male donor (AID).
The most common method of collection is either through intercourse, by the use of a special condom, or focused masturbation.  The male producing the sample is advised to abstain for about 2-3days to aid the quantity of sperm in the ejaculate, i.e sperm count.
It is important that the male patient producing the sample for the procedure and processing is aware of the need to collect the semen sample under sterile conditions with basic instructions as washing hands before and after collection, must not use soap on their body to aid collection, and samples must be collected into a sterile container or special condom supplied by the clinic.
The same instructions are given to donors attached to sperm banks; whose samples are usually frozen and quarantined and tested before they are released to be used on a patient.
Indications for Artificial Insemination
• Men who are unable to ejaculate inside their wife’s vagina for whatever reasons.  This is the classical indication.  Causes for ejaculation failure include diabetes, sclerosis, spinal cord injury and retrograde ejaculation, where sperm are released backward into the bladder instead of urethra.  Retrograde ejaculation may be due to diabetes, trauma or operation in the bladder neck or a side effect of certain drugs.
• Men with mildly low sperm count, poor quality sperm or antisperm antibodies.
• Men who wish to freeze their sperm for possible future use before vasectomy, chemotherapy or radiotherapy for cancer.
• Women with cervical mucus hostility or poor cervical mucus
• Couples with unexplained infertility
• Some infertility clinics may offer intrauterine insemination of a HIV negative woman with washed and prepared sperm of her HIV positive husband/partner.

Patient Preparation
A female patient would have her menstrual cycle monitored closely by various methods, which include monitoring body temperature, cervical mucus check, using the SBK index, which tells us the degree of elasticity of the mucus which is an indication of whether ovulation is likely to take place or not; Also ultrasound can be used for monitoring follicular development. Commercial ovulation kits and blood tests to measure the hormones; Luteinising hormone (LH) on days 13, 14, 15, 16, allows  the date of ovulation to be identified while day 21 Progesterone confirms that ovulation took place in a cycle.
Semen preparation
Semen samples that are frozen (cryo) are thawed at room temperature prior to use.  This is common with husbands sample stored in sperm banks prior to use.  And it is efficient in ensuring that sperms are available if the patient is unable to produce semen at the required time, or is unavailable due to logistics.
The semen produced is passed through a preparation procedure in the laboratory called ‘washing’.
This can be either swim up, swim down, or density gradient techniques with the aim of removing seminal plasma, containing prostanglandin which may cause cramps when introduced into the uterus, debris and bacteria etc. The aim being to increase the chances of fertilisation and remove dead or  non motile sperms, and mucous, from the semen. The resulting semen sample is then assessed for count, motility and progression.  These procedures improve the motility of semen sampled.
There are various commercial media which can be used; these include ‘Vitrolife’, ‘Origio’ or ‘Sage’ amongst others.  All these procedures are carried out at 370C, in vivo in the assisted reproduction laboratory.
The female patient is prepared by stimulatory drugs to stimulate the production of multiple follicles and induce ovulation, within
a required time.  The insemination can either be intra cervical, ICI i.e in the cervix, whereby raw semen can be used, intra uterine, IUI where only prepared semen can be introduced into the uterus, or fallopian intra tubal, ITI, whereby prepared sperms are deposited in the fallopian tube which is not commonly used. 
Frozen or fresh semen samples are processed as mentioned earlier, and inserted through a fine catheter into the cervix or uterus.
It is important that a highly trained professional carries out Artificial Insemination, for the safety of the patient.  After the patient is given a luteal phase support, which is progesterone in pessaries or injections from day 7 – 10 after insemination to increase the endometrial thickness to favour implantation.  It is normal for the patient to lie back for about 15mins after procedure. 
If the procedure is successful, a pregnancy would result in a live baby; and this type of pregnancy is not different from that conceived by sexual intercourse.  There are chances of multiples births, as a result of drugs used by the patient in a stimulatory cycle.
To achieve optimal chances of pregnancy, the woman should be under 30yrs of age, while the typical semen parameter for the man should be 10 X106 minimum counts;  40% motility; 1-2/4 progression.  The insemination should be done 2 to 3 times within a treatment cycle.  A good cycle should have at least two to three follicles measuring a minimum of 16mm, oestrogen level of 500pg/ml; on the day that HCG is given.
Pregnancy rate
Many factors influence the actual interpretation of success rate or pregnancy rates. These include health, age of women, type of stimulatory drug used, duration of infertility, cause of infertility, number quality of motile sperm etc.  There is no significant difference between couples whose infertility is unexplained using stimulated IUI and conception through natural means.
Typical results are 10 – 15% pregnancy rate per cycle using ICI, 15 – 20% using IUI, with 60 – 70% achieving pregnancies after 6cycles.  Pregnancy rate from our experience in Nigeria is at AIH: 20 -30%, D.I, 40 – 55% after 6cycles where there are no female factors.
Typical Complications
These include cramps, as a result of the prostaglandins in the semen, if not properly processed.  Also likely infection from the sample used and non sterile insemination technique, ovarian hyperstimulation syndrome (OHSS), and mix up of samples
It is important that consent must be obtained at all times, before any procedure is carried out.  For donor inseminations, it is best to use anonymous donors.
Typical cost per procedure could range from =N=12,000 to =N=100,000 per cycle depending on the dosage and type of stimulatory drugs used, and patient’s response.

culled from this day live

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