Semen analysis is the most common test of a man’s fertility as it measures several features of the sperm and seminal fluid. Some of the most important parameters of semen analysis are sperm count, sperm motility, sperm morphology, and fluid volume.

Sperm morphology is assessed with the help of a microscope, wherein they are checked for their shape. One must note that all men will have some percentage of abnormally shaped sperm, which is quite common. However, a much higher percentage of abnormally shaped sperm will result in difficulty of fertilisation and conception.

A normally shaped sperm is characterised by – an oval-shaped head, with a clean, distinct cap covering it and no drops of fluid, alongside a regular looking neck and mid-section and a single tail. In the case of abnormal-looking sperm, they have a round head, or two tails or two heads.

Currently, there is no conclusive manner of saying that abnormally shaped sperm will result in any genetically abnormal offspring. The abnormality only causes difficulty in penetrating the eggshell and fertilising it. But what happens post fertilisation is currently understood as the same for normal and abnormal cells.

Statistics reveal that the shape of the sperm is directly correlated to certain lifestyle choices of the individuals. Abnormal sperm shape has been evidenced in individuals consuming higher amounts of tobacco, alcohol, or caffeine. These substances can directly hurt the sperm DNA can cause abnormalities of shape and motility. There is evidence that suggests that the intake of dietary supplements and multivitamins helps sperm morphology.

What are the causes of altered sperm morphology?

Some of the common causes for abnormal sperm morphology can be enumerated as:

• Past or present infections
• Injury or trauma of the testicles
• Exposure to toxins
• Previous vasectomy or pelvic surgery
• Cancer treatment

Can an abnormal sperm fertilise? Is pregnancy possible?

Yes, theoretically speaking, the abnormally shaped sperm do have the possibility of fertilising an egg. However, given their abnormal shape, they may find it difficult to move faster and reach the egg. The eventual chance of pregnancy depends on the degree of abnormality in the sperm. For example, in spermatozoa without a head (no genetic content) or with a small or absent acrosome (necessary to penetrate the egg), fertilisation will not occur since they lack an essential part for the process.

Can abnormal sperm cause a miscarriage?

Yes. There is a possibility of miscarriage arising out of pregnancy that is caused by abnormal sperms. There is a likelihood of genetic abnormalities, making it difficult for the embryo to form and develop fully.