Impotence, hormonal imbalances, and dramatically decreased sperm quality are all caused by smoking.
Tobacco smoke contains more than 4,000 chemicals including a myriad of known carcinogens. The health consequences of smoke exposure are signiﬁcant and include numerous diseases and dysfunctions of the respiratory tract, increased risk of multiple types of cancer, and increased incidence of cardiovascular disease. But smoking can also have a negative impact on sperm quality. This is worth thinking about if you plan for a family.
The exposure to tobacco smoke has significant negative effects on semen quality. For example, one study showed – in a cross-sectional analysis of 2,542 healthy men over 12 years – that cigarette smokers had lower sperm quality and sperm count compared to men who didn’t smoke .
Here is the science of how cigarette smoking affects sperm quality, and in turn, your chances of starting a family.
Sperm volume and seminal fluid
Sperm is made up of seminal plasma, the ﬂuid component of ejaculation, which plays a major role in male fertility. This ﬂuid contains a huge variety of organic and inorganic molecules. This provides both nutrition and protection to sperm cells traveling through the female reproductive tract. The chemicals in tobacco smoke not only lowers the sperm volume, but also decreases the protective seminal fluid components. As a result, the sperm cells get a lower survival chance.
Several clinical studies have reported that smokers have lower sperm quality compared to non-smokers. In a study including 1,786 men, smoking was associated with a decrease in sperm counts by 17.5% and in total motile sperm cells by 16.6% when compared to non-smokers.
Research shows that smoking can lead to male infertility through a decrease in reproductive hormones (FSH and testosterone, amongst others), which are essential for sperm production.
A sperm cell’s ability to swim (motility) is highly important for overall sperm quality. The better swimmers, the better the chances of reaching and fertilizing an egg.
Smoking increases Reactive Oxygen Species (ROS). ROS are biologically active, oxygen-containing free radicals that have the ability to damage DNA and kill sperm cells. This is called oxidative stress, which you can read more about here. This sperm DNA-damage negatively impacts sperm motility. Therefore, more “bad” swimmers are produced, lowering overall semen quality.
Sperm size and shape
Several studies confirm that men who smoke have fewer well-shaped sperm cells than non-smokers . Smoking affects the shape of sperm cells, resulting in structural abnormalities such as curved tails. Badly-shaped sperm cells aren’t good swimmers and don’t have the best chances of survival when compared to normal looking sperm cells. This leads to decreased ability to fertilize an egg and thereby lower chances of reaching pregnancy.
Besides alterations in sperm shape, size, volume, and quality, some studies have looked into sperm DNA in smokers. The men who smoke seem to have increased DNA fragmentation (the separation or breaking of DNA strands into pieces), which may be associated with problems of fertilization and embryo development. Some studies suggest that the DNA fragmentation in the sperm cells even can be transferred to the baby.
Overall, this can also mean that chances of pregnancy are poorer, even with artificial insemination or IVF treatment.
Erectile dysfunction or other sexual impairments can have a huge impact on your ability to make your partner pregnant. Several studies show that smoking associates with a high risk of erectile dysfunction (ED). ED affects around 20% of all men and up to 52% of males aged 40–70 years .
The biology behind an erection is that healthy blood vessels dilate and get filled with blood. When you smoke, the lungs absorb toxins from the cigarette smoke. Those toxins cause damage to the vessels in the penis (scientifically; decrease in vessel dilation) and impair blood flow, resulting in ED. Having trouble raising the rifle doesn’t mean that you are producing bad sperm, but if you have ED, you won’t be able to deliver your semen inside the woman you love to get her pregnant.
There have been several studies that clearly find exposure to cigarettes while in the womb can have an impact on a man’s fertility in the future.
One study of 1,770 men demonstrated that those who had prenatal exposure to smoking had over 20% lower sperm density as adults than those without exposure . Other studies have found lower sperm concentration when making the same comparison.
It’s never too late – there is hope
Not all is lost – the impact of smoking is quite reversible for most men. So, it’s never too late to quit cigarettes and stop damaging your sperm cells! The process of making new sperm cells takes around 70-90 days. This means that you can see an improved sperm quality around 3 months after you stop smoking. However, it may take a little longer if you have been a heavy smoker for a long time.