Impact of smoking on fertility among men and women
Infertility is a rising concern in the recent past and infertility rates are nearly double among smokers compared to non-smokers. Even one cigarette a day prolongs the time needed for a couple to conceive. People who smoke often consume alcohol too, adding to its deleterious effects.
How does it affect fertility In males
Cigarette smoking is injurious to health as it contains several toxic substances including gases like carbon monoxide and particles like tar, nicotine, lead and cadmium. Nicotine is mainly metabolized in the body to cotinine which is known to affect sperm motility. Cadmium and lead reduce sperm density, motility and structure. Cigarettes also increase the DNA fragmentation rate of sperms. Electronic cigarettes have a similar composition as cigarettes but with lower levels.
Tobacco chewing is less harmful than cigarettes but also has high levels of nicotine. It is also known to affect sperm concentration, structure, viability and motility in addition to causing lung cancer and heart diseases.
Sperms mature and develop their tails in the epididymis but smoking interferes with this process and can cause detached ciliary tufts.
Smoking affects the sperm chromatin integrity thereby decreasing the fertility rate.
Lower levels of the enzyme creatinine kinase in smokers reduce sperm motility. Acrosin is another enzyme released by the sperm head which is required for sperm penetration into the ovum and these levels are lower in smokers.
Smoking also increases the levels of white blood cells and reactive oxygen species in the body creating an oxidative stress environment which is can be deleterious to the sperm count, motility and viability. Ascorbic acid is a natural antioxidant of the body and levels in smokers are up to 40% lower adding to the oxidative stress.
Passive smoking is not immune to the ill effects of smoking and it can reduce sperm motility too. Both active and passive smoking can be associated with erectile dysfunction
Smoking tends to reduce both prostate and seminal vesical parameters in smokers.
Certain components of tobacco smoke may interfere with the functioning of the center controlling hormone levels, in turn influencing the Sertoli and Leydig cell function and affecting sperm quality. Smoking reduces the blood supply and oxygen delivery to the testis affecting its functioning.
How does it affect fertility in females
Smoking has a wide range of deleterious effects on a woman’s fertility. It can cause fallopian tube blockage and higher rates of tubal pregnancies. It may affect the microenvironment of the follicles, alter hormone levels and damage the eggs in the ovaries which in turn can result in deformities in the fetus, higher miscarriage rates and preterm deliveries. Women are born with a fixed number of eggs and damaged eggs unlike sperms cannot be replaced, hence smokers may experience menopause one to four years prior to non-smokers. Smoking also increases the thickness of the egg wall making sperm penetration difficult. It also affects the lining of the uterus rendering it unfavorable for the implantation of the embryo. In addition to infertility, it may also cause cervical cancer.
Though IVF may be offered, it will not completely eliminate the ill effects of smoking on fertility. 30% lower IVF pregnancy rates have been reported among women smokers. There is no need to lose hope of quitting even after years of smoking. It improves fertility rates and reduces the risk of abortions, fetal deformities and preterm births. Smoking cessation has been shown to improve both sexual and general health. In addition to this, your doctor will prescribe certain medications including antioxidants which will help improve the sperm quality and reverse the effects of oxidative stress.
(This article is attributed to B. Ramesh, Founder and Chief Laparoscopic Surgeon, Infertility Specialist and Uro-Gynaecologist, Altius Hospital, Bengaluru)
(Disclaimer: The opinions expressed in this article are those of the author. They do not reflect the views of India TV)
