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Cited by 24Sperm and Testicular FunctionReproductive Health and TechnologiesMale Reproductive Health Studies

Sperm morphology: classification drift over time and clinical implications

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Morbeck, Dean E., Leonard, Phoebe H., Weaver, Amy L., Shimek, Katherine M., Bouwsma, Esther V.A., Coddington, Charles C.·2011·Fertility and Sterility
DOI 10.1016/j.fertnstert.2011.08.036
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Abstract

Objective To assess sperm morphology with Tygerberg (strict) and World Health Organization (WHO) 3rd criteria for intrauterine inseminations (IUI) between two eras to determine if there was a difference in pregnancy rates. Design Retrospective study. Setting Academic institution. Patient(s) 127 couples with 290 IUI treatments during 1996-97 (era 1) and 133 couples with 317 IUI treatments during 2005-06 (era 2). Intervention(s) None. Main outcome measure(s) Pregnancy rates per cycle and couple. Result(s) Average sperm morphology was higher in era 1 than era 2 for both WHO 3rd (37 ± 13% vs. 23 ± 10%) and strict criteria (8.0 ± 5.0% vs. 4.0 ± 3.0%). Pregnancy rates per cycle were 5.9% versus 19.8% in era 1 and 16.7% versus 19.3% in era 2 for couples with WHO 3rd morphology <30% or ≥30%, respectively. Pregnancy rates per cycle were 2.7% versus 15.0% in era 1 and 13.3% versus 14.7% in era 2 for couples with strict morphology ≤4% or >4%, respectively. Conclusion(s) There was a strong relationship between morphology and IUI outcome in era 1 that was not present in era 2. These results suggest that classification drift increased the percentage of men diagnosed with teratozoospermia and resulted in a loss of predictive value.

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  • Studies examining sperm morphology and pregnancy outcomes following IUI and IVF have produced variable results.

    “In the context of these aforementioned limitations, studies have been performed examining sperm morphology and pregnancy outcomes following IUI7891011 and IVF112131415161718 with variable results.”

    From Men with a complete absence of normal sperm morphology exhibit high rates of success without assisted reproduction (2017) · cites this paper as [7]

    The Results and Discussion report that sperm morphology predicted clinical pregnancy after IUI in the earlier era but not the later era, supporting variable IUI findings. The paper mentions IVF in its background but does not examine pregnancy outcomes following IVF, so it does not support that part of the claim. (LLM, conf=0.86)

    Experimental — accuracy not yet measured

  • The cut-off of 4% in the fifth edition was criticized as being too low, resulting in poor prediction of ART outcomes.

    “Although some research found a good correlation between the strict classification of sperm morphology and pregnancy outcome, the cut-off of 4% in the fifth edition was criticized as being too low, resulting in poor prediction of ART outcomes (31).”

    From Isolated teratozoospermia: revisiting its relevance in male infertility: a narrative review (2024) · cites this paper as [31]

    The Results and Discussion report that a 4% strict-morphology threshold did not predict pregnancy in the later IUI era. But the same threshold was predictive in the earlier era, and the paper attributes the loss of predictive value to classification drift, not to the fifth edition’s cut-off being too low. The study concerns IUI outcomes, rather than ART outcomes generally. (LLM, conf=0.87)

    Experimental — accuracy not yet measured

  • Some research found a good correlation between the strict classification of sperm morphology and pregnancy outcome.

    “Although some research found a good correlation between the strict classification of sperm morphology and pregnancy outcome, the cut-off of 4% in the fifth edition was criticized as being too low, resulting in poor prediction of ART outcomes (31).”

    From Isolated teratozoospermia: revisiting its relevance in male infertility: a narrative review (2024) · cites this paper as [31]

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Cites

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2 of the 42 references couldn’t be matched to a known paper.

Research works printed but not linked: 3

  1. World Health Organization. Laboratory manual for the examination of human semen and sperm- cervical mucus interaction. 3rd ed. Cambridge: Cambridge University Press; 1992.
  2. Cooper TG, Noonan E, von Eckardstein S, Auger J, Baker HWG, Behre HM, et al. World Health Organi- zation reference values for human semen characteris- tics. Hum Reprod Update 2010;16:231-45.
  3. World Health Organization. Laboratory manual for the examination and processing of human semen. 5th ed. Geneva: WHO Press; 2010.

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Authors
Morbeck, D. E., Leonard, P. H., Weaver, A. L., Shimek, K. M., Bouwsma, E. V. A., & Coddington, C. C.
Affiliations
Mayo Clinic (US)
Corresponding author
Morbeck, Dean E.
ORCID
Venue
Fertility and Sterility
Publisher
Elsevier BV
Published
2011-12
Volume
96
Issue
6
Pages
1350-1354
ISSN
0015-0282 (ISSN-L)
DOI
10.1016/j.fertnstert.2011.08.036
OpenAlex
W2013234055
Cited by
24
References
42
Citations by year
2025: 2 · 2024: 3 · 2023: 1 · 2022: 1 · 2021: 1 · 2020: 3 · 2018: 2 · 2017: 2 · 2016: 4 · 2015: 2 · 2013: 2 · 2012: 1
FWCI
1.06
Type
journal article
Language
en
Open access
Licence
Locations
  • Fertility and Sterility (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Health Sciences › Medicine › Reproductive Medicine › Sperm and Testicular Function
  • Health Sciences › Medicine › Reproductive Medicine › Reproductive Health and Technologies
  • Health Sciences › Health Professions › General Health Professions › Male Reproductive Health Studies
Keywords
sperm morphology, intrauterine insemination, pregnancy rate, teratozoospermia, male infertility, diagnostic criteria revision
MeSH terms
Adult, Female, Humans, Infertility, Male, Insemination, Artificial, Male, Pregnancy, Retrospective Studies, Spermatozoa, Time Factors, Pregnancy Rate, Cell Shape, Semen Analysis

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