Low Sperm Motility: Tips for Getting PregnantFertility Treatment
Fertilization happens when a sperm cell meets an egg cell in the fallopian tube. This process is successful when both sperm and egg are healthy. Sperm motility is necessary for a good conception; however, other factors such as semen volume, sperm count, and sperm morphology are also important.
The failure to conceive a child may have various causes for both men and women. Among the most important reasons for male infertility, we can mention sperm problems such as low sperm motility, low sperm count, abnormal sperm morphology, thick semen, and azoospermia. Low sperm motility is considered one of the most common causes of male infertility and refers to the disability of sperm to move toward an egg and fertilize it.
What Is Sperm Motility?
Sperm motility is the movement, or swimming, of sperm. A healthy sperm can reach a motility speed of at least 25 micrometres per second. One of the most common causes of infertility in men is asthenozoospermia (or asthenospermia) which is the medical term for low sperm motility. In this condition, sperm do not reach and fertilize the egg successfully.
The Sperm Path for Pregnancy
Sperm are initially produced and developed in men's testicles. During ejaculation, millions of sperm cells are set free to find an egg and fertilize it. It usually takes 72 days for the sperm cell to be fully mature and gain fertility power. In this stage, following a healthy diet and exposure to standard temperature play important roles in producing healthy sperm.
In the next stage, the mature sperm pass through the epididymis; however, some are lost along the way. Also, the remaining sperms after ejaculation in the man's body are destroyed spontaneously. Therefore, usually, about 100 million sperm gets the opportunity to enter the woman's body.
The sperm also has to pass through another problematic pathway which goes through the vagina into the uterus and reaches the fallopian tubes. The acidic walls of the vagina, which are meant to protect against infection, can damage some sperms. However, a sperm-friendly fluid makes it easier for sperm to move toward the egg during the fertile window.
In this path, many sperm are recognized as foreign cells and attacked by white blood cells, so they move in different directions. The remaining sperm must reach the fallopian tubes to find an egg and fertilize it. However, it is difficult for the sperm to find the fallopian tubes, and only a few can reach there. Finally, the strongest and healthiest sperm penetrates the egg and creates a pregnancy.
How Does Sperm Motility Affect Pregnancy?
The way a sperm move is another important factor in creating a pregnancy. There are two kinds of sperm motility, progressive and non-progressive. Progressive motility refers to sperm that move along a straight line or around large circles. Non-progressive movement refers to sperm that can still move but is often slow and not in a straight line. For example, a sperm that vibrates in place would be considered motile but non-progressive. A sperm that zigzags but makes forward progression would be considered progressive. The sperm should have progressive motility to swim to the female reproductive tract.
Amount of Motile Sperm
Usually, each ejaculation of a man contains over 39 million sperm. However, not all of those sperm are expected to be completely healthy. For an ejaculate sample to be considered normal, at least 40% of the sperm should be motile or moving. However, this amount can include sperm with non-progressive movements; at least 32% of them should show progressive motility. A total motile sperm count of over 20 million is considered normal to create a pregnancy, while having less than 5 million motile sperm is abnormal and reduces the chance of having a successful pregnancy. Also, less than 1 million motile sperm shows a severe fertility problem.
What Is a Normal Sperm Speed for Getting Pregnant?
Based on the type of movements, sperm are classified into four grades during sperm analysis.
- Grade A: Sperm with progressive motility. They move fast in a straight line at a speed of at least 25 μm per second.
- Grade B: Non-linear motility; they move forward but tend to travel at a lower speed (up to 25 μm/sec).
- Grade C: Non-progressive motility; sperm of this group move in their place, do not move forward, and make rotational or oscillatory movements.
- Grade D: Immotile sperm; they do not move at all.
In a normal semen analysis or spermogram, the ejaculate must contain at least 25% of sperm of grade "A" or at least 50% of spermatozoa combined from groups "A" and "B."
Low Sperm Motility Diagnose
Some tests can be performed to find the cause of infertility; however, receiving the results sometimes may take several months. Semen analysis is an essential male fertility test. At first, the urologist reviews the patient medical history and performs a physical examination. Next, a semen sample is collected to study sperm formation, size, appearance, speed, and count. Through this test, the physician can find the existence of any disorder and suggest an appropriate treatment for it. Besides semen analysis, blood tests are also performed to look for hormonal problems.
The sample is collected by masturbating into a sterile container to perform a sperm analysis test. It is recommended to avoid ejaculation within 3-5 days before the test so that the quality of semen reaches its highest level. Smoking and alcohol should also be avoided in the days before the test to increase the accuracy of the test results.
Sperm Motility Measurements
The following factors evaluate sperm motility in semen analysis:
- Motile sperm percentage;
- Percentage of motile sperm concentration;
- Average path velocity (VAP);
- Sperm morphology;
- Total Motile Sperm Count (TMSC);
- Semen volume;
- Semen PH.
We will explain the above factors in detail in the following:
Motile sperm percentage
It refers to the number of motile sperm in a single ejaculate, usually presented as millions of cells per ml.
Percentage of motile sperm concentration
This factor shows the density of motile sperm per unit volume of semen. The lower limits of sperm concentration leading to infertility are about 60 million per millilitre (cc). However, if this amount reaches 20 million per cc, there will still be a chance of pregnancy, especially with assisted reproductive technologies. It should also be noted that the sperm count can range from 28 million to 225 million per millilitre.
Average path velocity (VAP)
The VAP factor shows how fast a sperm travel per second (μm/s).
Total Motile Sperm Count (TMSC)
This factor shows how many sperm swim in a single ejaculate, which determines the probability of improving male fertility.
As said above, the semen volume in each ejaculation affects the chance of fertility. A semen volume lower than an average of 2 to 5 ml per ejaculation may be associated with seminal vesicle problems or prostate gland disorders. More semen volume probably indicates a low concentration of sperm. We should say that the small volume of semen cannot protect the sperm against the acidic fluid inside the vagina. Furthermore, a large volume of semen leads to excessive dilution and increases the possibility of losing sperm inside the vagina.
The semen PH level plays a significant role in sperm function. By measuring the semen PH level, problems such as infection can be identified and treated. The normal semen PH is between 7.2 and 7.8. An acidic ejaculate with lower pH (less than 7.2) may indicate blockage of seminal vesicles, while one with a more pH is usually associated with infections.
Typically, 90% of male sperm have a normal shape, varying from 66 to 99%. A rise in the number of sperm with abnormal shapes increases the probability of male infertility. The chance of fertility is almost zero if more than 8-10% of sperm have abnormal shapes. However, the healthy shape of sperm increases their mobility and reduces the possibility of infertility caused by low sperm motility.
How Long Do Sperm Stay Motile?
The survival time of sperm depends on various factors based on environmental conditions. When sperm are inside a woman's body, they can live for 4 to 6 days in the proper condition. Therefore, sexual intercourse during the days leading up to ovulation increases the chance of conception.
We should note that sperm cannot survive for long in the acidic environment of the vagina. Furthermore, research shows that Y-chromosome-bearing sperm - male gender - are more sensitive to the acidity of the vagina and may die sooner.
When Does Low Sperm Motility Occur?
Low sperm motility occurs when the result of the sperm analysis test shows that half of the sperm do not move progressively at a speed of 25 micrometres per second.
How to Get Pregnant with Low Sperm Motility
There are different treatment methods for low sperm motility. However, they are often not that effective. Low sperm motility usually causes problems such as infertility or false pregnancy, which may lead to abortion or curettage.
It is recommended to treat low sperm motility before trying to get pregnant. However, if no treatment is effective, the following new reproductive methods are available:
- IVF method: In the IVF method, the woman's egg is mixed with sperm in a laboratory, and then the fertilized egg is transferred into the uterus.
- IUI method: During the IUI treatment, sperm is placed directly into the uterus by a small tube. This method solves the problem of the sperm's difficult passage and not reaching the egg.
- Microinjection method (ICSI): Treatment with ICSI and IVF is almost identical. Their difference is in the way the sperm fertilizes the egg. In IVF, the egg and sperm are left in a petri dish to fertilize. In ICSI, one sperm is directly injected into the egg.
What Is the Lowest Sperm Count for IUI?
As sperm motility affects male fertility, the minimum number of sperm needed for IUI should be estimated. The minimum number of motile sperm needed for IUI method is usually similar to the same amount in a natural pregnancy. In men without infertility problems, one ejaculate of semen may contain over 39 million sperm. Not all of those sperm, however, are expected to be completely healthy. Therefore, for an IUI to be successful, at least 40% of the sperm should be motile, and at least 32% of them should show progressive motility.
According to studies, at least 1 million motile sperm counts (TMSC) are needed for a successful IUI. TMSC of less than 1 million indicates very low sperm mobility. It is recommended to perform IUI with at least 5 million moving sperm, since in most cases, 1-5 million motile sperm do not lead to a successful IUI pregnancy.
A total motile count of over 20 to 30 million is considered normal for pregnancy by the IUI method. Low sperm motility condition is usually diagnosed based on the "percentage" of motile sperm, however, the total "number" of mobile sperm has a better value. Furthermore, a more successful IUI requires using some fertility medication such as letrozole, clomiphene citrate, or gonadotropin.