September 2007

Monthly Archive

Insemination Methods

Posted by admin on 28 Sep 2007 | Tagged as: Uncategorized

Artificial insemination was developed to treat certain types of infertility. It involves manually introducing sperm into the reproductive tract of a woman in order to help her get pregnant. It’s particularly useful if a man is unable to ejaculate during sexual intercourse or has sperm with low motility which might be unable to reach the egg after intercourse. It has also been used for women with thick cervical mucus which hinders the passage of sperm. It is the method of choice for inseminating a surrogate mother if she is relying on using her own fertilized eggs rather than having an embryo implanted in her uterus.

The sperm can be either fresh or frozen-thawed. The latter is strongly recommended because the processes involved in freezing minimize the chance that infectious microorganisms will be present.

The procedure must be timed to coincide with ovulation, whether this occurs naturally or is stimulated by hormone treatment. The most accurate way to determine the onset of ovulation is to monitor hormone levels in blood or urine; this gives better results than monitoring body temperature or vaginal discharge.

There are several methods of insemination; the success rate for most of them is around 15 to 30%.

1. Intrauterine insemination (IUI). IUI involves introducing sperm directly into the uterus via a catheter. This is an invasive method but has a higher success rate. Washed sperm must be used to avoid uterine cramping due to prostaglandins in unprocessed semen. IUI tends to be more successful if used in combination with fertility drugs, although several cycles are often needed before the woman gets pregnant.

2. Intracervical insemination (ICI). ICI is less expensive and invasive than IUI and also has good success rates. Because the sperm are deposited in the cervix rather than the uterus, they must be motile, so his method is unsuitable for infertility due to low-motility sperm. Sperm washing increases the chance of a successful outcome.

3. Intravaginal insemination (IVI). IVI is the simplest insemination technique and involves introducing sperm into the vagina, as is done during normal intercourse. It is not normally necessary to use washed sperm unless there is a known risk of infection from the semen. Since the sperm have to swim to the uterus, they must be motile.

4. Intratubal insemination (ITI). ITI is an uncommon and highly invasive (and expensive) method. Since sperm are deposited directly in the fallopian tubes, close to where the eggs are located, the success rate tends to be higher than for the other techniques. This technique can be performed if IUI is unsuccessful.

5. Intrafollicular insemination (IFI). IFI involves introducing sperm directly into the ovarian follicles where the eggs are developing. This is a very invasive procedure and does not have an especially high success rate. It appears to have no advantages over IFI.

After the insemination procedure, the woman should remain lying down for a few minutes; she can then resume normal activity. If the procedure does not result in pregnancy, it can be repeated. If pregnancy does not result after six treatments, further medical consultation is advisable.

Sperm Washing

Posted by admin on 28 Sep 2007 | Tagged as: health

Sperm washing is a technique to prepare sperm for use in artificial insemination. Whether they are to be frozen or not, sperm should be subjected to this process. During the sperm-washing process, sperm are separated from the seminal fluid and from other constituents of semen such as chemicals and microorganisms. Some of the sperm-washing techniques also allow live sperm to be separated from dead or deformed sperm, a step which greatly increases the likelihood of a successful outcome of the insemination procedure.

Washed sperm are needed for intrauterine insemination of women hoping to get pregnant, because unprocessed semen contains prostaglandins which may cause severe cramping if the semen is introduced directly into the uterus. The washing process also removes bacteria and viruses from the sperm and helps avoid infections in the woman and even in the resulting child. As a result of the success of sperm washing in removing viruses, it’s now a real possibility for an HIV-positive man to have a child with an HIV-negative woman without risking that she and the child will be infected.

There are three main sperm-washing techniques, and the choice of technique depends on the type of sperm contained in the semen to be treated.

1. The swim-up method. This technique is suitable for normal semen samples. The semen sample is placed in a test tube and covered with a layer of washing medium. Sperm, which tend to swim upward, swim up into the medium, leaving behind the seminal fluid and dead sperm which are unable to swim. Only sperm which are sufficiently healthy and motile to swim up into the washing medium are collected, so this technique results in a high-quality sample. After being collected, the medium is centrifuged to concentrate the sperm, which are separated from the medium and then prepared for storage.

2. The centrifugation method. This method is used for semen samples containing sperm with low motility and for samples with a low sperm count. Low-motility sperm are less likely to be able to swim up into the washing medium without help, so the swim-up method is not suitable for sperm collection in this case. In the centrifugation method, the semen sample is mixed with the washing medium, and the mixture is centrifuged until the sperm separate out as a pellet. The pellet is collected from the centrifuged sample, suspended in more medium, and centrifuged again. This step can be repeated several times to ensure a pure sample.

3. The density gradient method. This is another centrifugation method, which is suitable for highly viscous samples and those with abnormal cells and debris. Washing media of different densities are layered in a tube, and the semen is added on top. Viable sperm are separated into the pellet after centrifugation, whereas the abnormal cells and debris are trapped in the different layers of medium. As with the regular centrifugation method, the density gradient process is repeated several times to ensure that the pellet eventually contains a pure sample.

Sperm samples are analyzed by the lab for abnormalities both before and after the washing process. The sperm-washing process thus results in a high-quality sperm sample with a good chance of successfully and safely fertilizing the eggs of a woman wishing to get pregnant.