The effects of cigarette smoking on male fertility
Jason R. Kovac
, Abhinav Khanna
& Larry I. Lipshultz
Urology of Indiana, Male Reproductive Endocrinology and Surgery, Carmel, IN, USA, and
Department of Urology, Baylor College of Medicine,
Houston, TX, USA
Cigarette smoking, one of the main causes of preventable morbidity and mortality, has a multi-
tude of well-known side effects. The relationship between cigarette smoking and infertility has
been studied for decades; however, large-scale, population-wide prospective studies are lacking.
The majority of the current literature is in the form of retrospective studies focused on the effects
of smoking on semen analyses. This article discusses the results of these studies and reviews the
postulated mechanisms. The effects of smoking on assisted reproduction and
in vitro
outcomes are noted. The consequences of smoking while pregnant on future fertility as well as
the outcomes of second-hand smoke are analyzed. The current evidence suggests that men
should be advised to abstain from smoking in order to improve reproductive outcomes.
Smoking, male infertility, semen parameters,
outcomes, zinc,
in vitro
Received 18 June 2014
Accepted 6 August 2014
Published online 19 February 2014
It has been estimated that over one third of all men globally
smoke some form of tobacco and that 21.6% of American
men smoke cigarettes [1]. Smoking has been linked to a
myriad of adverse health outcomes, including cardiovascular
disease, respiratory disease, and cancer of the lungs, bladder,
cervix, esophagus, kidney, pancreas, and stomach [2]. More
recently, researchers have begun to explore the relationship
between cigarette smoking and reproductive health.
The American Society for Reproductive Medicine defines
infertility as the inability to achieve pregnancy following
12 months of regular, unprotected sexual intercourse [3]. It
has been estimated that up to 15% of all couples attempting
to have children face some form of infertility [4]. Although
almost half of all cases of infertility are due exclusively to
female factors, the male factor is the sole etiology in approxi-
mately 30% of couples. An additional 20% of infertile cou-
ples have a combination of male and female factors. Thus,
male factor infertility plays a significant role in 50% of all
couples with infertility [5]. This review examines the litera-
ture to elucidate the potential effects of cigarette smoking on
male infertility.
Materials and methods
A PubMed/Medline search was conducted of the literature
from 1960 to March 2014. The search was performed using
combinations and derivatives of the following terms:
ing, male infertility, outcomes, in vitro fertilization, semen
analysis, morphology, prenatal (or) maternal smoking,
second-hand smoking
. The Related Citations in PubMed link
from the U.. National Library of Medicine was used to screen
additional abstracts related to the aforementioned searches. In
excess of 1000 manuscripts were screened using title search,
related links, and abstract summaries. Applicable studies
were read and included in this current review.
Effects of smoking on semen analysis parameters
Smoking has been shown to have a detrimental effect on vari-
ous parameters of semen analysis. A cross-sectional analysis of
2542 healthy men from 1987 to 2004 by Ramlau-Hansen et al.
[6] found that on semen analysis, cigarette smokers had lower
semen volumes, sperm counts, and percentage of motile sperm
compared to men who did not smoke. Further, it was suggested
that the relationship between smoking and sperm concentration
was dose-dependent. Indeed, men who smoked
20 cigarettes
per day experienced a 19% reduction in sperm concentration
compared with nonsmokers, even after controlling for age,
recent fevers, and duration of abstinence as well as diseases in
reproductive organs. It was concluded that adult smoking
resulted in moderate impairment of semen quality.
In another large cohort of 1786 men undergoing infertility
workup (655 smokers and 1131 nonsmokers), Kunzle et al.
[7] demonstrated that smoking was associated with decreases
in sperm density (15.3%), total sperm counts (17.5%), and
total motile sperm (16.6%) compared with nonsmokers. Fur-
thermore, morphology (percent of normal forms) as well as
ejaculate volume was slightly affected by smoking but not to
any significant degree. Effects on ejaculate volume were
Correspondence: Dr. Jason R. Kovac, MD PhD FRCSC, Male Reproductive Endocrinology and Surgery, 12188-A North Meridian Street, Suite 200,
Carmel, IN, USA. Tel: +1 317 564 5100. E-mail:
2015 Informa UK Ltd.
ISSN: 0032-5481 (print), 1941-9260 (electronic)
Postgrad Med, 2015; 127(3): 338
DOI: 10.1080/00325481.2015.1015928
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