Cannabis makes sperms weaker

Dr Allan Pacey

In a recent research by the Universities of Sheffield and Manchester to examine how aspects of day-to-day lifestyle influence the size and shape of sperm, it has been found that the young men who use cannabis may be putting their fertility at risk.

As announced, the conducted research is among the largest studies to be ever done in the world. The study also revealed that the samples ejaculated in the summers (June to August) were worse in size and shape of sperm whereas, were found to be better in men who had desisted from any sexual activity for six days and more. However, other habits like smoking cigarettes or drinking alcohol appeared to have little effect on the semen.

The research, done on a large scale, had 1,970 men being evaluated and compared. A total of 318 men, who gave samples, had less than 4% of the correct size and shape while rest of them resulted above that rate. The later half was considered to be ‘normal’ by the current medical definitions.

According to the researchers, the study reveals that the men who produced less than four percent of normal sperm were likely to have used cannabis in the three months period prior to ejaculation. This deficiency was mostly found in the youngsters below the age of thirty.

Dr Allan Pacey, Senior Lecturer in Andrology at the University of Sheffield, said: “Our knowledge of factors that influence sperm size and shape is very limited, yet faced with a diagnosis of poor sperm morphology, many men are concerned to try and identify any factors in their lifestyle that could be causing this. It is therefore reassuring to find that there are very few identifiable risks, although our data suggests that cannabis users might be advised to stop using the drug if they are planning to try and start a family”.

The earlier studies had also revealed that the sperm with poor morphology (size and shape) swim weakly in the woman’s body following sex. This is due to their abnormal shape which makes them less efficient and results in infertility.

However, the researchers say that the study somewhere failed to find any association between sperm morphology and other common lifestyle factors, such as cigarette smoking or alcohol consumption. Hence, there remains a possibility that they could correlate with other aspects of sperm that have not been measured yet, such as the quality of DNA contained in the sperm head.

This study was funded by the UK Health and Safety Executive, the UK Department of Environment, Transport and the Regions, the UK Department of Health and the European Chemical Industry Council.

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