Cohort studyindependent cross-checkabstract checked I-PPI-109 standard review
No link between PPIs and sperm quality
Proton-pump inhibitor use does not affect semen quality in subfertile men.
Overview
Keihani S et al.. Asian J Androl 2018 · PMID 28879865 · DOI 10.4103/aja.aja_35_17
Among men at a fertility clinic, those taking PPIs had similar semen results to men taking no medicines.
Does the study support the specific claim? No · Methodological quality: low
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Check PPIs and semen quality.
- How was the study done?
Retrospective cohort.
- How many people, animals or samples were studied?
248 PPI users, 7698 controls.
- What was actually found?
No significant differences.
- How large was the observed effect?
Not significant.
- What do the results mean in everyday life?
No sign that PPIs harm sperm.
- What are the study's limitations?
Weak design.
- What does it say about Elawady's specific claim?
Contradicts infertility claim (weakly).
- Do the results apply to Germany and Europe?
Applicable.
- What can explicitly not be concluded from this study?
Cannot exclude small effects.
Scientific in-depth review
1. Full reference
- Authors
- Keihani S et al.
- Journal
- Asian J Androl
- Year
- 2018
- Identifier
- PMID 28879865 DOI 10.4103/aja.aja_35_17
- Verification
- verified – PubMed efetch 2026-10-26 + Crossref 2026-10-26
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
NCATS/NIH support (PubMed)
2. Research question
Is PPI use associated with semen quality in subfertile men?
3. Study design and population
- Study design
- Cohort study – Retrospective cohort of fertility-clinic patients
- Population
Subfertile men at a US fertility clinic
- Country
USA
- Period
2003-2013
- Sample size
12,257 reviewed; 248 PPI users (258 samples); 7698 controls without medication
- Inclusion and exclusion criteria
PPI use >3 months before semen collection; spermatotoxic drugs excluded
4. Methods and endpoints
- Exposure / intervention
PPI >3 months
- Comparator
No medication
- Endpoints
Conventional semen parameters
- Statistical methods
Linear mixed-effects models adjusted for age
5. Actual results
- Results
PPI use (alone or with non-spermatotoxic drugs) was not associated with statistically significant changes in semen parameters.
- Absolute risks
Not applicable
- Authors' conclusion
PPI use was not associated with detrimental effects on semen quality.
6. Strengths
- Large clinic database
7. Weaknesses
- Retrospective
- Only age adjusted
- Subfertile population; no fertility outcome
8. Risk of bias
- Orienting tool
- ROBINS-E
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- high
- Rationale
Minimal adjustment; exposure self-reported.
9. Assessment of the statistical interpretation
Null; precision limited by 248 exposed men.
10. Relevance to the specific claim
Only identified study on PPIs and male fertility parameters: no adverse association.
11. Independent contrary findings
Earlier small report suggested adverse changes (cited by authors).
12. Transferability to Germany and Europe
Moderate.
13. Overall methodological judgement
Weak evidence, but contrary to the infertility claim.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | low |
| Risk of bias | high |
| Precision of results | low |
| Directness | indirect |
| Reproducibility | unknown |
| Consistency with the overall evidence | unknown |
| Regional transferability | moderate |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
Fertility outcomes; erectile function data lacking.