Last Updated on October 11, 2023 by SCRAdmin
What is Abnormal Sperm Morphology?
The size and shape of the sperm (called sperm morphology) is an important factor in determining male fertility. Sperm that are normally-shaped have an oval head and a long tail.
However, abnormal sperm morphology (teratozoospermia, or teratospermia) occurs when sperm possess certain defects in shape or size, such as a head that is too large, too small, or misshapen, or with double, crooked, or coiled tails. These irregularities could affect the sperm’s ability to reach and penetrate an egg.
Nevertheless, it is not uncommon to have a high percentage of sperm that are deformed. The majority of sperm from a given semen sample are abnormal – in fact, only 4-10% of them will be in the normal range.
What Qualifies As Normal-Shaped Sperm?
Normal sperm have the following characteristics:
- A smooth oval-shaped head measuring 5 to 6 micrometers in length, and 2.5 to 3.5 micrometers in width (smaller than the tip of a needle).
- A distinctly-formed cap (acrosome) covering between 40-70% of the sperm head.
- There is no apparent abnormality in the tail, midpiece or neck.
- The sperm head does not contain fluid droplets that are larger than half the size of the sperm head.
Causes Of Poor Sperm Morphology
There are several environmental factors that can affect sperm morphology. These factors include:
- Exposure to toxins: Exposure to certain chemicals, such as pesticides and heavy metals, can damage the structure of sperm cells and affect their ability to swim and fertilize an egg.
- Poor diet and nutrition: A healthy diet rich in antioxidants and essential vitamins and minerals is important for maintaining good sperm health. Deficiencies in certain nutrients, such as zinc and selenium, can negatively impact sperm morphology.
- Exposure to excess heat: Sperm production and function can be impaired by high temperatures, such as those caused by hot tubs, saunas, and tight-fitting clothing.
- Alcohol and drug use: Excessive alcohol consumption and the use of certain drugs, including anabolic steroids and marijuana, can affect sperm morphology and fertility.
- Stress: Chronic stress can have negative effects on sperm production and quality, including morphology.
It’s important to note that these factors can also impact overall sperm health and fertility. If you’re concerned about the health of your sperm, it’s a good idea to speak with a healthcare professional for advice and guidance.
How Does Abnormal Sperm Morphology Affect Fertility?
Most male fertility experts will tell you that it is not known what importance sperm morphology has in predicting a successful pregnancy. Indeed, it is not considered a reliable predictor of infertility unless almost 100% of the sperm are abnormal.
Additionally, a semen analysis indicating abnormal sperm morphology does not necessarily mean you’re infertile. Although it might take a little longer, you can still conceive a child with low scores from a semen analysis.
Keep in mind that if you and your partner can’t have children through sexual intercourse, assisted reproduction technology like IVF (in vitro fertilization) may also be an alternative.

Can A Sperm with an Abnormal Shape Fertilize an Egg?
Yes, even though a sperm may exhibit abnormal morphology, it can still potentially reach and fertilize an egg. That said, some studies have shown that infertility in men can be caused by having larger amounts of abnormally-shaped sperm.
Producing greater numbers of abnormally-shaped sperm is typically associated with other semen-related issues, such as a low sperm count or poor motility. However, some men with high amounts of abnormal sperm may still have no problems getting their partner pregnant.
Do Abnormal Sperm Increase the Risk of Birth Defects?
This is currently not known. We do know that there is no apparent relationship between a sperm’s genetic material and its shape. Fertilization is still likely to occur once the sperm reaches the egg.
That said, some abnormalities in sperm structure may be due to genetic problems. This means that male offspring could potentially inherit the same morphology abnormalities possessed by the father.
Is the Shape of Sperm Important to Fertilization?
It is not clear why (or if) a sperm’s shape may be important to fertilization. Although men with atypically shaped sperm can have more difficulty causing pregnancy, it is not possible to know whether this is due to the actual shape of the sperm, or some other factor that affects fertility and also causes defects in sperm shape.
How to Improve Sperm Morphology
There are a few changes you can make to improve sperm morphology. You should avoid the use of tobacco, as some research suggests that smoking might negatively impact fertility.
You should also avoid using marijuana and other recreational drugs while you’re trying to conceive, and limit your alcohol intake as well. These substances can affect the quality of your sperm’s genetic material (DNA).
There has not been any evidence linking caffeine intake to changes in sperm morphology. Keep in mind that it may take as much as 3 months for any changes in your sperm to be noticed.
Supplements to Improve Sperm Morphology
Nutritional supplements for male fertility are a popular, less invasive, and less expensive way to improve your sperm morphology compared to medical treatments. Because these supplements are generally safe, effective, and readily available, they are one of the first methods that men use to improve morphology and overall fertility.
Supplements like Semenoll, Semaxin, and Fertility Factor 5 are made with ingredients that have been shown to improve not only morphology, but also sperm count and motility as well. Additionally, these supplements boost total semen volume and support overall male reproductive health.

Janice Reilly is the Deputy Editor of Content at The Sperm Count Report. She has extensive experience as a writer and editor for medical news blogs, where she covered fitness, reproductive health, nutritional supplementation, and similar subjects.