Sandro Esteves, MD, PhD

DirectorANDROFERTCenter for Male Reproduction and InfertilityCampinas, BRAZIL

Will the new WHO Standards

for Semen Examination Changethe Clinical Management of

Male Infertility?

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“Understanding Infertility” – New Delhi, India – August 2011

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Learning Objectives

Present the new WHO reference values for semen analysis

Understand how the new values were obtained• Merits and demerits

Reclassifying SA according to new limits• Implications for clinical practice

Debate is open • Should the new WHO reference values be adopted ?

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Semen Analysis

Paramount importance

on initial male infertility

evaluation

surrogate measure of

fertility status

Functional status male reproductive

system

volume, count,

motility, morphology

influenced by several factors

do not account subcellular

dysfunctions

Semen characteristics

WHO 1980

WHO 1987

WHO 1992

WHO1999

WHO 2010

Volume (mL) ND ≥ 2 ≥ 2 ≥ 2 ≥ 1.5

Sperm count (106/mL) 20-200 ≥ 20 ≥ 20 ≥ 20 ≥ 15

Total sperm count (106) ND ≥ 40 ≥ 40 ≥ 40 ≥ 39

Total motility (%) ≥ 60 ≥ 50 ≥ 50 ≥ 50 ≥ 40

Progressive motility ≥ 2 ≥ 25% ≥ 25% (a) ≥ 25% (a) ≥ 32% (a+b)

Vitality (%) ND ≥ 50 ≥ 75 ≥ 75 ≥ 58

Morphology (%) 80.5 ≥ 50 ≥ 30 (14)* ≥ 4*

Leukocyte count (106/mL) < 4.7 < 1.0 < 1.0 < 1.0 < 1.0 *Strict (Tygerberg) criterion

Cut-off reference values for semen characteristics as published in consecutive

WHO manuals

New WHO references valuesHow they were obtained

1,953 semen samples of recent fathers Time to pregnancy (TTP) ≤ 12 mo 5 studies in 7 countries on 3 continents Laboratories with QC only Morphology by strict criterion (Kruger) Progressive and non-progressive motility Lower reference limits (5th centile)

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  Centiles

  5% 50%* 95%

Volume (mL) 1.5 3.7 6.8

Sperm count per mL (x106) 15.0 73.0 213.0

Sperm count per ejaculate (x106) 39.0 255.0 802.0

% Motility (total) 40 61 78

% Motility (progressive) 32 55 72

% Normal (strict criteria) 4 15 44

% Alive (eosin-nigrosin staining) 58 79 91

Cooper et al: World Health Organization reference values for human semen characteristics. Hum Reprod Update 16: 231-245, 2010

Percentile distribution of semen characteristics values of recent fathers whose partners had a TTP ≤ 12

months, used to establish the reference limits in the 2010 WHO manual

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New WHO references valuesHow they were obtained

“Studies were conducted in different regions of the world with some areas over-represented, such as Northern Europe, and others, such as Africa, parts of Europe and Central and South America, under-represented”

“The values presented are considered to represent global semen characteristics of fertile men”

Cooper TG, Noonan E, von Eckardstein S, Auger J, Baker H, Behre H, Haugen T, Kruger T, Wang C, Mibzvo MT, Vogelsong K

World Health Organization reference values for human semen characteristics.

Hum Reprod Update 16: 231-245, 2010

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New WHO references valuesCritical Appraisal

USA(Columbia, NYC, Minneapolis, LA)

AUSTRALIA (Melbourne)

NORWAY(Oslo)

FINLAND(Turku)

DENMARK (Copenhagen)

FRANCE(Paris)

UK(Edinburgh)

??

??? ?

Study Year Country TTP < 12 months stated

Sperm morphology evaluation criterion

Overlapping authorship or collaboration

among authors

Bonde et al. 1998 Denmark Yes David YesSlama et al. 2002 France,

Denmark, UK, Finland

Yes David, Tygerberg

Yes

Swan et al. 2003 USA No Tygerberg Yes

Haugen et al. 2006 Norway Yes Tygerberg No

Stewart et al. 2009 Australia Yes Tygerberg Yes

Studies used to establish the new limits for human semen characteristics in the

5th ed WHO Manual

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New WHO references valuesCritical Appraisal - Summary

Reasons for lower cutoff

Merits Demerits

Different way of generating data:

• Method for semen analysis (higher QC standards; strict morphology)

• Population studied

Controlled studies No systematic review of fertile populations:

• Not representative of global fertile male population

Recent fathers with known TTP

Standardized semen analysis

Morphology using different criteria

Single semen specimen of each individual

Indications for assisted reproductive techniques

Varicocele treatment

Referrals for male partner evaluation

New WHO reference values• Implications for Clinical Practice

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Implications for Practice• Referrals for male partner evaluation

Semen characteristics

Patient Specimen

Reference limits

WHO1999

WHO 2010

Volume (mL) 2.3 ≥ 2 ≥ 1.5

Sperm count (106/mL) 16.5 ≥ 20 ≥ 15

Progressive motility 40 ≥ 50% (a+b)

≥ 32% (a+b)

Vitality (%) 65 ≥ 75 ≥ 58

Morphology (%) 9 (14) ≥ 4

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Implications for Practice• Reclassification of semen analysis reports

Abnormal results

WHO 1999

Reclassified as “Normal”

WHO 2010

(38.7%)

Couples (N=987) with infertility duration > 12 months

Source: ANDROFERT, Brazil

Morphology results accounted for 53% of reclassification

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Male Infertility Evaluation – much more than a simple semen analysis -

Implications for Practice• Varicocele treatment

Va

ric

oc

ele • 35% of

male infertility cases

Su

rgic

al

Tre

atm

en

t• Effect• Decrease seminal oxidative stress• Improve sperm DNA integrity• Improve semen parameters• Increase the likelihood of

spontaneous and assisted pregnancy

• Treatment Recommendation:• Clinical (palpable) varicocele and• Abnormal semen analysis results

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Implications for Practice• Varicocele treatment

• Health insurance issues• Authorization not granted• Reimbursement refused

Previous candidates for treatment now

not eligible if semen parameters are

above the WHO 5th centile

• Higher spontaneous pregnancy rates after varicocelectomy in men with clinical varicocele and mild oligozoospermia or normozoospermia than with moderate to severe oligozoospermia

Facts

Kamal KM, Jarvi K, Zini A: Microsurgical varicocelectomy in the era of assisted reproductive technology: influence of initial semen quality on pregnancy rates. Fertil Steril 75: 1013-1016, 2001.

Richardson I, Grotas AB, Nagler HM: Outcomes of varicocelectomy treatment: an updated critical analysis. Urol Clin North Am 35:191-209, 2008.

Normal Varicocele grade 2 Varicocele grade 3

87.8

49.937.4

62.956 55.6

8.4 7.3 6.1

Adolescents with and without Varicocele

Sperm count (million/mL) Progressive motility (% a+b)Morphology (%)

Mori et al. Does varicocele grade determine extent of alteration to spermatogenesis in adolescents? Fertil Steril 90: 1769-1773, 2008.

P=0.003 P<0.001

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Implications for Practice• Indications for ART

• Severe male factor infertilitySemen analysis results fall below

new reference limits

ICSI

• < 5% strict morphology thresholds currently used

• Indications unlike to change due to new WHO reference values

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Implications for Practice• Indications for ART

IUI• Mild male factor infertility• Unexplained male infertility

• Impact of new WHO reference values likely to be minimal

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Implications for Practice• Indications for ART- Summary

WHO reference semen values not suitable to indicate treatment modality

Merely represent the

distribution of semen

profile of a group of

recent fathers

Choice of ART should be based on:

Clinical features of each case Center’s experience and reported results with different ART modalities

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Debate is open • Should the new WHO reference

values be adopted ?

Expanding the interpretation of the new WHO reference values: focus on the 50th percentile

Laboratories seeking to adopt the new standard should determine the strategy that would aid the clear communication of the clinical significance of the results

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Practical Points

In 2010, WHO reported evidence-based reference values for semen characteristics of fertile men that are much lower than those in previous editions.

Reference values are not representative of global semen characteristics of fertile men and cannot be misinterpreted as a sign of sperm quality decline.

Reference values do not accurately discriminate fertile and infertile men. A comprehensive infertility workup, including sperm function testing, is crucial to assess the male fertility potential.

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Practical Points

Adoption of the new limits will have a profound impact on diagnosis of male infertility and treatment of conditions such as varicocele.

However, its impact on ART indication is likely to be minimal.

WHO should have allowed for an extensive debate within the scientific community before publishing these values.