CoChat
Sign Up
Cited by 3Sperm and Testicular FunctionSmoking Behavior and CessationMale Reproductive Health Studies

Evaluating the effect of smoking and its cessation on semen parameters

Open access
Ragheb, Ahmed, Abdelbary, Ahmed, Massoud, Amr, Abd Elkhalek, Mahmoud, Elbatanony, Ahmed·2025·Reproduction and Fertility
DOI 10.1530/raf-24-0135PMC PMC12579508
Open this paper in CoChat — free account

Abstract

Our primary aim was to investigate the reversibility of the negative impact of smoking on male fertility. Secondarily, we studied the effect of both time after smoking cessation as well as the smoking index on semen quality improvement. Our study included 60 participants who applied to a smoking cessation program. The volunteers started by completing a fertility background questionnaire. Two semen specimens, provided 2 weeks apart, were analyzed according to the WHO guidelines for each candidate on three different occasions. The first was right before smoking cessation, followed by the 2nd and 3rd at 3 and 6 months after stopping smoking. Semen quality was compared between the three occasions. The degree of change was correlated with the level of smoking. The nicotine level in urine was used for smoking cessation compliance monitoring during the study. Comparing semen quality on the three different occasions, we detected a significant improvement in semen volume (3.33 mL ± 1.07 vs 3.88 mL ± 0.80 vs 4.34 mL ± 0.67, P < 0.001), sperm concentration (14.77 million /ml ± 6.49 vs 17.71 million/ml ± 6.41 vs 19.27 million/ml ± 6.46, P < 0.001), total sperm count (49.33 million ±25.31 vs 70.16 million ±30.85 vs 84.01 million ±31.00, P < 0.001), progressive motility (20.7 vs 35.3% vs 42.28%, P < 0.001), total motility (41.48 vs 60.33% vs 67.67%, P < 0.001), and abnormal morphology (69.32 vs 50.88% vs 40.82%, P < 0.001). Improvement in all parameters was positively correlated to time after cessation. Higher smoking indices were related to higher levels of improvement in semen volume, sperm concentration, and total count (areas under the curve of 0.867, 0.852, and 0.863, respectively, P < 0.001 for each). Our conclusion was that the negative effect of smoking on semen quality is reversible. Smoking cessation has a time-dependent positive effect on main semen parameters, hence positive potential for fecundity improvement in men. Lay summary: Extensive research efforts have always focused on the negative effects of smoking on male reproduction by comparing fertility in smokers versus non-smokers. There are very few studies looking at the effect of smoking cessation on male fertility. Our primary aim was to investigate whether the negative impact of smoking on male fertility was reversible. Our study included 60 participants who applied to a smoking cessation program. The volunteers started by completing a fertility background questionnaire. Each candidate provided two semen specimens 2 weeks apart, on three occasions. The first was right before smoking cessation, followed by the 2nd and 3rd at 3 and 6 months after stopping smoking. Semen quality was compared between the three occasions. The degree of change was correlated with smoking levels. We found the negative effects of smoking on semen are reversible.

Verified 2026-11-05 · 1 reference not checked yet

AI snapshot

Written from the paper’s full text.

TL;DR

In a prospective cohort of 60 male smokers undergoing cessation, semen quality improved significantly at 3 and 6 months after quitting, with improvements positively correlated with time since cessation. Higher smoking index predicted greater improvement in semen volume, sperm concentration, and total sperm count.

Key findings

  • Significant improvements were seen from baseline to 3 and 6 months after smoking cessation in semen volume (3.33 ± 1.07 vs 3.88 ± 0.80 vs 4.34 ± 0.67 mL), sperm concentration (14.77 ± 6.49 vs 17.71 ± 6.41 vs 19.27 ± 6.46 million/mL), total sperm count (49.33 ± 25.31 vs 70.16 ± 30.85 vs 84.01 ± 31.00 million), progressive motility (20.7% vs 35.3% vs 42.28%), total motility (41.48% vs 60.33% vs 67.67%), and abnormal morphology (69.32% vs 50.88% vs 40.82%), all P < 0.001.
  • Semen pH did not change significantly over the study period (P = 0.26). Sperm vitality improved and semen leukocyte count decreased significantly after 3 and 6 months (P < 0.001).
  • Higher smoking index was associated with ≥20% improvement in semen volume (median 17.75 vs 10, P < 0.001), sperm concentration (median 17 vs 9, P < 0.001), and total sperm count (median 15.5 vs 7.5, P < 0.001).
  • ROC analysis showed the smoking index predicted improvement in semen volume (AUC 0.867), sperm concentration (AUC 0.852), and total sperm count (AUC 0.863), all P < 0.001; optimal cutoffs were >13 pack-years for volume and >12 pack-years for concentration and total count.

Methods

  • Prospective cohort study with longitudinal follow-up: 200 male smokers aged 20–50 seeking cessation were invited, 69 enrolled, and 60 completed after 9 dropouts.
  • Participants provided two semen specimens 2 weeks apart at baseline, then at 3 and 6 months after confirmed smoking cessation; semen analysis followed WHO 2010 criteria, and urinary cotinine dipstick was used to monitor compliance.
  • Smoking index was calculated as packs per day × years of smoking; statistical analysis used Minitab 17.1.0.0, with paired t-tests, Mann–Whitney U tests, and ROC analyses.

Limitations

  • The paper states no fertility outcomes such as pregnancy or live birth were assessed, so semen parameter improvements may not guarantee conception.
  • The paper states there was no non-smoking control group and potential confounding from diet or occupational exposure; hormonal assessments (testosterone, LH, FSH) were not conducted.
  • Evident from the text: follow-up was limited to 6 months, so longer-term durability of improvements and reproductive outcomes remain unassessed.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1530/raf-24-0135

Cites

41 of 42 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

3 of 7 cited sources checked · 0 supported · 0 flagged · accuracy not yet measured

  • Premisecitation

    There is a significant gap in the literature regarding the potential reversibility of smoking's effects on male fertility following smoking cessation.

    “Despite the well-documented adverse impact of smoking on male fertility, there remains a significant gap in the literature regarding the potential reversibility of these effects following smoking cessation.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites Tang et al. 2019 source

      The Introduction identifies a gap in evidence on whether smoking-related differences in semen quality persist after cessation, particularly among fertile men. But the broader claim about a continuing gap concerning reversibility of effects on male fertility goes beyond that scope: the Discussion reports two earlier cessation studies showing improved semen quality and presents this study’s own findings on former smokers. (LLM, conf=0.82)

      Experimental — accuracy not yet measured
  • Findingown data

    The smoking index predicted improvement in semen volume with an AUC of 0.867.

    “The smoking index demonstrated strong predictive performance, with areas under the curve (AUC) of 0.867 for semen volume, 0.852 for sperm concentration, and 0.863 for total sperm count (P < 0.001 for all).”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: A ≥20% improvement of any semen parameter is considered significant.
  • Findingown data

    No statistically significant difference in smoking index was detected in relation to changes in tail abnormalities.

    “no statistically significant differences in smoking index were detected in relation to changes in mid-piece abnormalities (P = 0.618), tail abnormalities (P = 0.383), or leukocyte count (P = 0.194), (Table 3).”
    Quote in the paperNot a substantial claim
  • Findingown data

    Improvement in all semen parameters was positively correlated with time after smoking cessation.

    “Improvement in all parameters was positively correlated to time after cessation.”
    Quote in the paperSubstantial claim
  • Findingown data

    Semen pH did not show a significant change throughout the study period.

    “In contrast, semen pH did not show a significant change throughout the study period (P = 0.26).”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim. 10
  • May combine two claims. 4

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Toxic metals such as cadmium and lead in cigarette smoke disrupt seminal zinc homeostasis and elevate oxidative stress, impairing reproductive function.

    “In addition, toxic metals such as cadmium and lead present in cigarette smoke are known to disrupt seminal zinc homeostasis and elevate oxidative stress, further impairing reproductive function (Machado-Neves 2022, Estevan et al. 2025).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites Machado-Neves 2022

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Estevan et al. 2025 source

      The Results (§3.1; page not provided) identify cadmium and lead in reference cigarette smoke as toxic to fertility. The Discussion (§4.1.3) links cadmium’s reproductive toxicity to oxidative stress and interference with zinc, but does not specifically describe disruption of seminal zinc homeostasis. Its lead discussion (§4.1.5) does not attribute either zinc disruption or oxidative stress to lead. (LLM, conf=0.88)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    Smoking negatively affects semen quality, impairing sperm concentration, motility, morphology, and volume.

    “Several studies, including meta-analyses (Sharma et al. 2016, Bundhun et al. 2019), have consistently demonstrated that smoking negatively affects semen quality, impairing parameters such as sperm concentration, motility, morphology, and volume (Mostafa et al. 2018, Osadchuk et al. 2023).”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites Sharma et al. 2016 source
    • cites Bundhun et al. 2019 source

      The Abstract Results and Discussion report lower sperm count and more morphological defects among infertile male smokers, supporting the broad claim that smoking harms semen quality. But this meta-analysis found no significant effect on motility, and its listed endpoints do not include semen volume. The findings are also specific to infertile males. (LLM, conf=0.91)

      Experimental — accuracy not yet measured
    • cites Mostafa et al. 2018

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Findingown data

    Sperm vitality significantly improved after 3 months of smoking cessation and continued to rise at 6 months.

    “Sperm vitality also improved significantly after 3 months of smoking cessation and continued to rise by the 6-month mark (P < 0.001).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Semen leukocyte count significantly decreased after 3 months of smoking cessation, with a further significant reduction at 6 months.

    “the semen leukocyte count showed a significant decrease after 3 months, with a further significant reduction observed at 6 months (P < 0.001)”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Study design and conductown data

    Detailed information on participants' smoking behavior was collected and considered during data analysis to control for potential confounding variables.

    “In addition, detailed information regarding participants’ smoking behavior, including type, dose, and duration of smoking, was collected through a structured questionnaire and considered during the data analysis to control for potential confounding variables.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    The absence of a non-smoking control group is a limitation of the study.

    “Other limitations include the absence of a non-smoking control group and potential confounding factors, such as diet or occupational exposure.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data

    Written informed consent was obtained from all participants before enrollment.

    “Written informed consent was obtained from all individuals before their enrollment.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data

    The study was approved by the Research Ethics Committee of the Faculty of Medicine, Beni-Suef University.

    “The study was initiated only after obtaining approval from the Research Ethics Committee of the Faculty of Medicine, Beni-Suef University (Approval No.: FMBSUREC/03112020/Mohammed).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning

    The study's sample size calculation determined a minimum required sample size of 44 participants.

    “Using a significance level of 0.05 and a type II error of 20% (power = 80%), the minimum required sample size was determined to be 44 participants.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Vine et al. (1994) source
    • The authors state this as an assumption: A mean difference of 30 with a standard deviation of 60 in semen volume would be clinically meaningful following smoking cessation.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    Potential confounding factors such as diet or occupational exposure are limitations of the study.

    “Other limitations include the absence of a non-smoking control group and potential confounding factors, such as diet or occupational exposure.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    Hormonal assessments (e.g. testosterone, LH, FSH) were not conducted.

    “Furthermore, hormonal assessments (e.g. testosterone, LH, FSH) were not conducted and may offer valuable mechanistic insights.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Study design and conductnone given

    Semen analysis was conducted according to the World Health Organization (WHO) 2010 criteria.

    “Semen analysis was conducted according to the World Health Organization (WHO) 2010 criteria, assessing sperm count, motility, and morphology.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Study design and conductnone given

    Compliance with smoking cessation was verified by measuring urinary cotinine levels using a dipstick method.

    “Compliance with smoking cessation was verified by measuring urinary cotinine levels using a dipstick method, which provided a qualitative positive or negative result.”
    Quote in the paperSubstantial claim
13 of 13

  • The authors state this as an assumption.

    A ≥20% improvement of any semen parameter is considered significant.

    “We assumed that ≥20% improvement of any parameter is considered significant using the Mann–Whitney U test.”

  • The paper relies on this without support.

    Spermatogenesis is a cyclical process occurring over approximately 74–90 days.

    “Given that spermatogenesis is a cyclical process occurring over approximately 74–90 days, these findings suggest that the negative impact of smoking on sperm parameters may be partially reversible within a few months of quitting.”

  • The authors state this as an assumption.

    A mean difference of 30 with a standard deviation of 60 in semen volume would be clinically meaningful following smoking cessation.

    “Based on a previous study by Vine et al. (1994) and focusing on semen volume as a key parameter of fertility, we assumed that a mean difference of 30 with a standard deviation of 60 would be clinically meaningful following smoking cessation.”

  • The paper relies on this without support.

    Participants who dropped out did not differ systematically from those who completed in a way that affects the results.

    “During the follow-up period, nine participants dropped out, resulting in a final sample of 60 individuals who completed the study.”

  • The paper relies on this without support.

    Changes in semen parameters over the follow-up were not due to unmeasured confounding factors such as diet or occupational exposure.

    “Other limitations include the absence of a non-smoking control group and potential confounding factors, such as diet or occupational exposure.”
5 of 5

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Semen-volume subgroup median differs from Table 3

    Major

    The results give a smoking-index median of 17.75 for participants with ≥20% improvement in semen volume; Table 3 gives 15.5 for that group.

  • Reported married proportion is not over 70%

    Minor

    The results say over 70% of participants were married, but Table 1 reports 42 of 60 participants, exactly 70%.

  • TZI standard deviation exceeds its reported range

    Minor

    Table 2 reports a TZI standard deviation of 0.129, although every reported TZI value lies between 1 and 1.02. A standard deviation cannot exceed that entire range of 0.02.

3 of 3

Cites

Flagged first, then by citations

Research works printed but not linked: 2

  1. Singh, 2014, Factors Influencing Semen Analysis in Cases of Infertility
  2. Zenoaga-Barbăroşie, 2024, : Human Semen Analysis: From The WHO Manual to The Clinical Management of Infertile Men

Cited by

Sorted by citations

Related

Authors
Ragheb, A., Abdelbary, A., Massoud, A., Abd Elkhalek, M., & Elbatanony, A.
Affiliations
  • Beni-Suef University (EG)
  • 2
ORCID
Venue
Reproduction and Fertility
Publisher
Bioscientifica
Published
2025-10-01
Volume
6
Issue
4
ISSN
2633-8386 (ISSN-L)
DOI
10.1530/raf-24-0135
PMC
PMC12579508
OpenAlex
W4414889259
Cited by
3
References
40
Citations by year
2026: 3
FWCI
2.26
Type
journal article
Language
en
Open access
Licence
Locations
  • Reproduction and Fertility (publishedVersion, cc-by)
  • Europe PMC (PubMed Central) (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Topics
  • Health Sciences › Medicine › Reproductive Medicine › Sperm and Testicular Function
  • Health Sciences › Medicine › Physiology › Smoking Behavior and Cessation
  • Health Sciences › Health Professions › General Health Professions › Male Reproductive Health Studies
Keywords
smoking, male fertility, semen quality, smoking cessation, semen volume, sperm concentration, total sperm count, sperm motility, sperm morphology, smoking index, nicotine, male infertility treatment, WHO guidelines
MeSH terms
Adult, Humans, Infertility, Male, Male, Nicotine, Semen, Smoking, Sperm Count, Sperm Motility, Smoking Cessation, Semen Analysis

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-11-05.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-11-05.

Cited sources are checked by gpt-6-sol.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review