Improved phenotypic classification of male infertility to promote discovery of genetic causes

An increasing number of genes are being described in the context of non-syndromic male infertility. Linking the underlying genetic causes of non-syndromic male infertility with clinical data from patients is important to establish new genotype-phenotype correlations. This process can be facilitated by using universal nomenclature, but no standardized vocabulary is available in the field of non-syndromic male infertility. The International Male Infertility Genomics Consortium aimed at filling this gap, providing a standardized vocabulary containing nomenclature based on the Human Phenotype Ontology (HPO). The "HPO tree" was substantially revised compared with the previous version and is based on the clinical work-up of infertile men, including physical examination and hormonal assessment. Some causes of male infertility can already be suspected based on the patient's clinical history, whereas in other instances, a testicular biopsy is needed for diagnosis. We assembled 49 HPO terms that are linked in a logical hierarchy and showed examples of morphological features of spermatozoa and testicular histology of infertile men with identified genetic diagnoses to describe the phenotypes. This work will help to record patients' phenotypes systematically and facilitate communication between geneticists and andrologists. Collaboration across institutions will improve the identification of patients with the same phenotypes, which will promote the discovery of novel genetic causes for non-syndromic male infertility.

Sex steroids and androgen biomarkers in the healthy man study: within-person variability and impact of fasting

OBJECTIVE

Serum testosterone measurements in clinical practice mostly utilize "direct" (non-extraction) immunoassays which have method-specific bias due to steroid cross-reactivity and nonspecific matrix artifacts. Although more accurate, sensitive, and specific liquid chromatography-mass spectrometry (LCMS) dominates in clinical research, the within-person variability of serum testosterone in healthy men using LCMS measurement is not reported.

DESIGN

Longitudinal multi-sampling observational study of men in excellent health over 3 months.

METHODS

Elite healthy men (n = 325) over 40 years of age in excellent, asymptomatic health provided 9 blood samples over 3 months with serum testosterone, dihydrotestosterone (DHT), estradiol (E2), and estrone (E1) measured by validated LCMS with conventional biochemical and anthropometric variables.

RESULTS

Quantitative estimates of within-person variability within day and between day, week, month, and quarter were stable other than an increase due to fasting. The androgen biomarkers most sensitive to age and testosterone among widely used biochemical and anthropometric variables in middle-aged and older men were identified.

CONCLUSIONS

This study provides estimates of variability in serum testosterone and the best androgen biomarkers that may prove useful for future studies of androgen action in male ageing.

Does being conceived by assisted reproductive technology influence adult quality of life?

Numerous studies have investigated the physical health and development of children and adolescents conceived with assisted reproductive technology (ART). Less is known about the quality of life of ART-conceived adults. This study explores the contributions of being conceived with ART and psychosocial cofactors present in young adulthood to the quality of life of adults aged 22-35 years. Young adults conceived through ART or natural conception (NC) completed questionnaires which included a standardized measure of quality of life (World Health Organization Quality of Life - Brief assessment (WHOQoL-BREF)) when aged 18-28 years (T1) and again when aged 22-35 years (T2). The WHOQoL-BREF has four domains: (i) Physical, (ii) Psychological, (iii) Social relationships and (iv) Environment. A total of 193 ART-conceived and 86 NC individuals completed both questionnaires. When accounting for other cofactors in multivariable analyses, being ART-conceived was strongly associated with higher scores (better quality of life) on the Social relationships, and Environment WHOQoL-BREF domains at T2. In addition, less psychological distress, a better relationship with parents, a better financial situation, and perceptions of being about the right weight at T1 were associated with higher scores on one or more of the WHOQoL-BREF domains at T2. In conclusion, being ART-conceived can confer advantages in quality of life in adulthood, independent of psychosocial cofactors.

Lifestyle and environmental risk factors for unexplained male infertility: study protocol for Australian Male Infertility Exposure (AMIE), a case-control study

BACKGROUND

Approximately 1 in 20 men are sub-fertile or infertile yet the aetiologies of male infertility remain largely unexplained. It is suggested that lifestyle choices and environmental factors contribute but research is limited. In particular, no study has evaluated early life exposures and subsequent male infertility. To address this knowledge gap, this study aims to characterise a cohort of men with idiopathic infertility and compare their general health, lifestyle choices and environmental exposures from teenage years onwards to men without reproductive abnormalities.

METHODS

Two groups of men (N = 500 cases; N = 500 controls), matched for age and socio-economic status, will be recruited from fertility clinics around Australia between June 2021 and June 2024. Men will be eligible if they are between 18 and 50 years, with a female partner less than 42 years, and have identified idiopathic male infertility (case) or are part of a couple with diagnosed female factor infertility but with no indication of compromised male fertility (control). Participants will complete an in-depth survey on general health, lifestyle and environmental exposures, reporting from teenage years onwards. An online medical data capture form will be used to gather fertility assessment information from participant medical records. Biological specimens of saliva (all study participants), blood and urine (optional) will be collected and stored for future genetic and epigenetic analysis. Differences in outcome measures between cases and controls will be determined using appropriate between groups comparisons. The relationship between explanatory variables and infertility will be analysed using multilevel modelling to account for clustering within fertility clinics.

DISCUSSION

This study addresses an important gap in research on the aetiology of male infertility and will provide a comprehensive profile of the lifestyle and environmental risk factors for male infertility, leading to provision of up-to-date health advice for male teenagers and adults about optimising their fertility.

Are Clinical Outcomes of Micro-TESE in Non-obstructive Azoospermic Men Affected by the Use of Fresh or Frozen Gametes?

Background: The combination of microsurgical testicular sperm extraction (mTESE) and intracytoplasmic sperm injection (ICSI) has become a common management option, with sperm motility being positively associated with successful outcomes. However, few studies have investigated whether the use of fresh or thawed gamete combinations affect clinical outcomes.

Objectives: To determine whether the clinical outcomes of ICSI cycles using mTESE recovered testicular sperm of non-obstructive azoospermia (NOA) patients are affected by using fresh or thawed gametes.

Material and Methods: A retrospective study was conducted of NOA patients who underwent mTESE between 2017 and 2020 at Monash IVF assisted reproductive clinics in Melbourne, Australia. The impact of gamete fresh/frozen status and sperm motility was investigated on clinical outcomes such as fertilization, blastocyst formation, clinical pregnancy, and live birth rates (LBRs).

Results:A total of 103 NOA patients underwent mTESE, with a 65.1% successful surgical-sperm-retrieval. In total 56 patients contributed to 68 ICSI cycles, with a 35.1% fertilization rate and 25% LBR per embryo transfer. Compared with fresh testicular sperm, thawed testicular sperm did not affect clinical outcomes, including LBRs [16.7% vs 12.0%; odds ratio (OR) 0.68 (0.18–2.70)]. However, the use of thawed oocytes had a negative effect on fertilization rates [fresh-oocytes, 37.8%; vitrified-oocytes, 34.5%; OR 0.86 (0.02–0.48)]. Cycles using only motile sperm had a greater fertilization rate than those using a combination of motile and non-motile sperm (49.6% vs 37.2%, p ¡ 0.05). Importantly, when exclusively non-motile sperm were available (n = 26 cycles) their injection resulted in a very low fertilization rate (2.7%) and no live births were recorded.

Conclusion: Micro-TESE is an effective treatment for NOA patients, with no clear advantage of using fresh over thawed sperm, however, the use of vitrified compared with fresh oocytes requires further investigation. Importantly, patients should be informed of the poor outcomes with the use of non-motile sperm in mTESE ICSI cycles.

Chronic testicular Chlamydia muridarum infection impairs mouse fertility and offspring development†

With approximately 131 million new genital tract infections occurring each year, Chlamydia is the most common sexually transmitted bacterial pathogen worldwide. Male and female infections occur at similar rates and both cause serious pathological sequelae. Despite this, the impact of chlamydial infection on male fertility has long been debated, and the effects of paternal chlamydial infection on offspring development are unknown. Using a male mouse chronic infection model, we show that chlamydial infection persists in the testes, adversely affecting the testicular environment. Infection increased leukocyte infiltration, disrupted the blood:testis barrier and reduced spermiogenic cell numbers and seminiferous tubule volume. Sperm from infected mice had decreased motility, increased abnormal morphology, decreased zona-binding capacity, and increased DNA damage. Serum anti-sperm antibodies were also increased. When both acutely and chronically infected male mice were bred with healthy female mice, 16.7% of pups displayed developmental abnormalities. Female offspring of chronically infected sires had smaller reproductive tracts than offspring of noninfected sires. The male pups of infected sires displayed delayed testicular development, with abnormalities in sperm vitality, motility, and sperm-oocyte binding evident at sexual maturity. These data suggest that chronic testicular Chlamydia infection can contribute to male infertility, which may have an intergenerational impact on sperm quality.

American Heart Association ideal cardiovascular health score and subclinical atherosclerosis in 22-35-year-old adults conceived with and without assisted reproductive technologies

STUDY QUESTION

Is ART related with the association of American Heart Association (AHA) ideal cardiovascular health score and markers of subclinical atherosclerosis?

SUMMARY ANSWER

The associations between AHA score and markers of subclinical atherosclerosis in ART and non-ART groups were similar in magnitude.

WHAT IS KNOWN ALREADY

Long-term consequences of ART on cardiovascular health are unknown.

STUDY DESIGN, SIZE, DURATION

The study cohort for the cross-sectional analyses consisted of 172 ART-conceived and 78 non-ART conceived individuals of same age (range 22-35 years).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Cardiovascular risk factor status was evaluated with American Heart Association (AHA) ideal cardiovascular health score consisting of seven factors (body mass index, blood pressure, total cholesterol, glucose, diet and physical activity, non-smoking). Carotid artery intima-media thickness (cIMT), arterial pulse-wave velocity (PWV) and retinal microvascular parameters were evaluated as markers of early atherosclerosis. Group comparisons in continuous variables were performed with t-tests. For categorical variables, comparisons were performed with chi-square tests. The relationships between AHA score and the markers of atherosclerosis were examined with linear regression analyses adjusted for age and sex.

MAIN RESULTS AND THE ROLE OF CHANCE

There was no difference in AHA ideal health score between the ART and non-ART groups; mean (SD) scores were 4.1(1.4) versus 4.0(1.5), respectively, P = 0.65. No differences were observed between groups for any individual ideal health metric (P always >0.2). AHA score was not associated with cIMT or retinal measures in either group (P always >0.05). An inverse association was observed between AHA score and PWV in the ART group (beta (95% CI) -0.18(-0.26 to -0.10)). A numerically similar relationship was observed in the smaller non-ART group (-0.19(-0.39 to 0.01)).

LIMITATIONS, REASONS FOR CAUTION

Even though this cohort is among the largest ART studies with extensive cardiovascular data, the sample is still relatively small and the statistical power is limited. As the study population was still in early adulthood, we were not able to evaluate the associations with clinical cardiovascular events, but utilized non-invasive methods to assess early markers of subclinical atherosclerosis.

WIDER IMPLICATIONS OF THE FINDINGS

These findings suggest that ART-conceived individuals do not have increased vulnerability for cardiovascular risk factors.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by a National Health & Medical Research Council Project Grant (APP1099641), The Royal Children's Hospital Research Foundation, Monash IVF Research and Education Foundation, and Reproductive Biology Unit Sperm Fund, Melbourne IVF. The authors have no conflicts of interest relevant to this article to disclose.

Australian men's fertility information seeking attitudes and behaviour: A qualitative investigation

OBJECTIVE

Most women and men want and expect to have children but increasing maternal and paternal ages reduce their ability to achieve this. Most research relating to childbearing has focused on women. The aim of this study was to explore reproductive-aged men's fertility information-seeking attitudes and behaviours.

METHODS

Focus group discussions were conducted with younger (18-30 years, 3 groups) and older (31-45 years, 3 groups) men, residing in urban, peri-urban or rural settings in Victoria, Australia. The topics covered included men's fatherhood aspirations and intentions, and their attitudes and behaviours relating to seeking information about fertility. Focus group discussions were audio-recorded and transcribed, and transcripts analyzed thematically.

RESULTS

Six focus group discussions were conducted with a total of 39 participants. Four key themes were identified: 1. 'No need for fertility-related information'; 2. 'Knowledge and awareness of fertility'; 3. 'Fertility is women's business'; and 4. 'Fertility and manhood'. Fertility and fertility information seeking was perceived by many participants as women's domain. While men did not seek information about fertility unless they experienced fertility difficulties, they reported learning about fertility through the lived experiences of others, predominantly family and friends who experienced infertility.

CONCLUSION

Fertility-related health promotion initiatives and reproductive health information targeting men are needed to encourage men to be active participants in reproductive decision making to optimize the chance of both women and men achieving their parenthood goals. Narrative health messages may be a successful way to convey fertility information to men.

Audit of oxygen administration to achieve a target oxygen saturation range in acutely unwell medical patients

PURPOSE OF THE STUDY

To evaluate documentation of a target oxygen saturation (SpO₂) range and ability to achieve this range in acutely unwell inpatients.

STUDY DESIGN

In this single-centre audit, patients with discharge diagnoses of pneumonia, heart failure and exacerbation of asthma or COPD admitted to Wellington Regional Hospital, New Zealand between 1 June 2019 and 31 August 2019 who received oxygen were identified. In those with a documented target SpO₂ range, the proportion of SpO₂ measurements in the observation chart which were within, above and below range were determined as well as the maximum and minimum SpO₂. Regression analysis was performed to determine whether these outcomes were influenced by the prescribed range, high-dependency care or the number of adjustments to oxygen administration.

RESULTS

268 admissions were screened. Of the 100 eligible admissions who received oxygen, a target SpO₂ range was documented in 62. The mean (SD) proportion of SpO₂ measurements within range was 56.2 (30.6)%. A hypercapnic target SpO₂ range was associated with a higher probability of an SpO₂ above range; multivariate OR 5.34 (95% CI 1.65 to 17.3, p=0.006) and a lower probability of an SpO₂ below range; multivariate OR 0.25 (95% CI 0.08 to 0.80) p=0.02. The mean (SD) maximum SpO₂ was similar in those with a target range of 92%-96% versus a hypercapnic range; 96.2 (3.0)% and 95.2 (3.4)%, respectively.

CONCLUSIONS

Oxygen prescription and delivery in this clinical setting was suboptimal. SpO₂ values above the designated range are common, particularly in patients with a hypercapnic target range.

Testosterone treatment to prevent or revert type 2 diabetes in men enrolled in a lifestyle programme (T4DM): a randomised, double-blind, placebo-controlled, 2-year, phase 3b trial

BACKGROUND

Men who are overweight or obese frequently have low serum testosterone concentrations, which are associated with increased risk of type 2 diabetes. We aimed to determine whether testosterone treatment prevents progression to or reverses early type 2 diabetes, beyond the effects of a community-based lifestyle programme.

METHODS

T4DM was a randomised, double-blind, placebo-controlled, 2-year, phase 3b trial done at six Australian tertiary care centres. Men aged 50-74 years, with a waist circumference of 95 cm or higher, a serum testosterone concentration of 14·0 nmol/L or lower but without pathological hypogonadism, and impaired glucose tolerance (oral glucose tolerance test [OGTT] 2-h glucose 7·8-11·0 mmol/L) or newly diagnosed type 2 diabetes (provided OGTT 2-h glucose ≤15·0 mmol/L) were enrolled in a lifestyle programme and randomly assigned (1:1) to receive an intramuscular injection of testosterone undecanoate (1000 mg) or placebo at baseline, 6 weeks, and then every 3 months for 2 years. Randomisation was done centrally, including stratification by centre, age group, waist circumference, 2-h OGTT glucose, smoking, and first-degree family history of type 2 diabetes. The primary outcomes at 2 years were type 2 diabetes (2-h OGTT glucose ≥11·1 mmol/L) and mean change from baseline in 2-h OGTT glucose, assessed by intention to treat. For safety assessment, we did a masked monitoring of haematocrit and prostate-specific antigen, and analysed prespecified serious adverse events. This study is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12612000287831.

FINDINGS

Between Feb 5, 2013, and Feb 27, 2017, of 19 022 men who were pre-screened, 1007 (5%) were randomly assigned to the placebo (n=503) and testosterone (n=504) groups. At 2 years, 2-h glucose of 11·1 mmol/L or higher on OGTT was reported in 87 (21%) of 413 participants with available data in the placebo group and 55 (12%) of 443 participants in the testosterone group (relative risk 0·59, 95% CI 0·43 to 0·80; p=0·0007). The mean change from baseline 2-h glucose was -0·95 mmol/L (SD 2·78) in the placebo group and -1·70 mmol/L (SD 2·47) in the testosterone group (mean difference -0·75 mmol/L, -1·10 to -0·40; p<0·0001). The treatment effect was independent of baseline serum testosterone. A safety trigger for haematocrit greater than 54% occurred in six (1%) of 484 participants in the placebo group and 106 (22%) of 491 participants in the testosterone group, and a trigger for an increase of 0·75 μg/mL or more in prostate-specific antigen occurred in 87 (19%) of 468 participants in the placebo group and 109 (23%) of 480 participants in the testosterone group. Prespecified serious adverse events occurred in 37 (7·4%, 95% CI 5·4 to 10·0) of 503 patients in the placebo group and 55 (10·9%, 8·5 to 13·9) of 504 patients in the testosterone group. There were two deaths in each group.

INTERPRETATION

Testosterone treatment for 2 years reduced the proportion of participants with type 2 diabetes beyond the effects of a lifestyle programme. Increases in haematocrit might be treatment limiting. Longer-term durability, safety, and cardiovascular effects of the intervention remain to be further investigated.

FUNDING

Australian National Health and Medical Research Council, Bayer, Eli Lilly, University of Adelaide, and WW (formerly Weight Watchers).

Features of the metabolic syndrome in late adolescence are associated with impaired testicular function at 20 years of age

STUDY QUESTION

Are early signs of metabolic disorder in late adolescence associated with features of impaired testicular function many years before the majority seek parenthood?

SUMMARY ANSWER

Adolescents with features of metabolic disorder at 17 years, or insulin resistance (IR) at 20 years of age, show impaired testicular function and altered hormone levels compared to those without metabolic disorder.

WHAT IS KNOWN ALREADY

Controversial evidence suggests a recent decline in sperm production potentially linked to environmental influences, but its cause remains unclear. Concomitant increases in obesity and diabetes suggest that lifestyle factors may contribute to this decline in testicular function. Although obesity has been associated with adverse testicular function in some studies, it remains unclear whether poor testicular function merely reflects, or causes, poor metabolic health. If metabolic disorder were present in adolescence, prior to the onset of obesity, this may suggest that metabolic disorder maybe a precursor of impaired testicular function.

STUDY DESIGN, SIZE, DURATION

The Western Australian Pregnancy Cohort (Raine) Study is a longitudinal study of children born in 1989-1991 who have undergone detailed physical assessments since birth (1454 male infants born). At 17 years of age, 490 boys underwent a hepatic ultrasound examination, serum cytokine assessment (n = 520) and a metabolic assessment (n = 544). A further metabolic assessment was performed at 20 years (n = 608). Testicular assessment was performed at 20 years; 609 had reproductive hormones measured, 404 underwent a testicular ultrasound and 365 produced a semen sample.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Testicular volume was estimated by ultrasonography, and semen analysis was performed according to World Health Organization guidelines. Concentrations of LH, FSH and inhibin B (inhB) in serum were measured by immunoassay and total testosterone by liquid chromatography-mass spectrometry.At 17 years of age, a liver ultrasound examination was performed to determine the presence of non-alcoholic fatty liver disease (NAFLD), and serum analysed for the cytokines interleukin-18 and soluble tumour necrosis factor receptor 1 and 2 (sTNFR1, sTNFR2).At 17 and 20 years of age, fasting blood samples were analysed for serum liver enzymes, insulin, glucose, triglycerides (TG), total cholesterol, high density lipoprotein and low density lipoprotein cholesterol, high sensitivity C-reactive protein and uric acid. The homoeostatic model assessment (HOMA) was calculated and approximated IR was defined by a HOMA >4. Anthropometric data was collected and dual energy X-ray absorptiometry measurement performed for lean and total fat mass. As at this young age the prevalence of metabolic syndrome was expected to be low, a two-step cluster analysis was used using waist circumference, TGs, insulin, and systolic blood pressure to derive a distinct high-risk group with features consistent with the metabolic syndrome and increased cardiometabolic risk.

MAIN RESULTS AND THE ROLE OF CHANCE

Men at age 17 years with increased cardiometabolic risk had lower concentrations of serum testosterone (medians: 4.0 versus 4.9 ng/mL) and inhB (193.2 versus 221.9 pg/mL) (P < 0.001 for both) compared to those within the low risk metabolic cluster. Men with ultrasound evidence of NAFLD (n = 45, 9.8%) had reduced total sperm output (medians: 68.0 versus 126.00 million, P = 0.044), testosterone (4.0 versus 4.7 ng/mL, P = 0.005) and inhB (209.1 versus 218.4 pg/mL, P = 0.032) compared to men without NAFLD.Men with higher concentrations of sTNFR1 at 17 years of age had a lower sperm output and serum concentration of inhB, with an increase in LH and FSH (all P < 0.05 after adjustment for age, BMI, abstinence and a history of cryptorchidism, varicocele, cigarette smoking, alcohol and drug use), compared to those without an elevated sTNFR1. Multivariable regression analysis, adjusting for confounders, demonstrated that men in the high-risk metabolic cluster at 20 years had a lower serum testosterone and inhB (P = 0.003 and P = 0.001, respectively). A HOMA-IR > 4 was associated with a lower serum testosterone (P = <0.001) and inhB (P = 0.010) and an increase in serum FSH (P = 0.015).

LIMITATIONS, REASONS FOR CAUTION

This study is limited by the sample size and multiple comparisons, and causality cannot be proven from an observational study. Due to a 3-year interval between some metabolic assessments and assessment of testicular function, we cannot exclude the introduction of a bias into the study, as some of the participants and their testicular function will not have been fully mature at the 17-year assessment.

WIDER IMPLICATIONS OF THE FINDINGS

Irrespective of a proven causation, our study findings are important in that a significant minority of the men, prior to seeking parenthood, presented co-existent features of metabolic disorder and signs of testicular impairment. Of particular note is that the presence of NAFLD at 17 years of age, although only present in a minority of men, was associated with an almost 50% reduction in sperm output at 20 years of age, and that the presence of IR at 20 years was associated with a 20% reduction in testicular volume.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by Australian NHMRC (Grant Numbers 634457, 35351417 and 403981) and received support from the Raine Medical Research Foundation, The Telethon Kids Institute, University of Western Australia, Women and Infants Research Foundation, Curtin University and Edith Cowan University. D.A.D., J.E.D., N.M., L.A.A., R.-C.H., T.A.M., J.K.O., L.J.B. have nothing to declare. R.J.H. is Medical Director of Fertility Specialists of Western Australia, has equity interests in Western IVF, and has received grant support from MSD, Merck-Serono and Ferring Pharmaceuticals. RMcL has equity interests in the Monash IVF Group. R.J.N. has equity interests in FertilitySA, and has received grant support from Merck Serono and Ferring Pharmaceuticals. D.J.H. has received institutional grant funding (but no personal income) for investigator-initiated testosterone pharmacology studies from Lawley and Besins Healthcare and has provided expert testimony to anti-doping tribunals and for testosterone litigation.This abstract was awarded the Fertility Society of Australia clinical exchange award for the oral presentation at ESHRE, Barcelona, in 2018.

A high-volume, low-cost approach to participant screening and enrolment: Experiences from the T4DM diabetes prevention trial

BACKGROUND/AIMS

Participant recruitment to diabetes prevention randomised controlled trials is challenging and expensive. The T4DM study, a multicentre, Australia-based, Phase IIIb randomised controlled trial of testosterone to prevent Type 2 diabetes in men aged 50-74 years, faced the challenge of screening a large number of prospective participants at a small number of sites, with few staff, and a limited budget for screening activities. This article evaluates a high-volume, low-cost, semi-automated approach to screen and enrol T4DM study participants.

METHODS

We developed a sequential multi-step screening process: (1) web-based pre-screening, (2) laboratory screening through a network of third-party pathology centres, and (3) final on-site screening, using online data collection, computer-driven eligibility checking, and automated, email-based communication with prospective participants. Phone- and mail-based data collection and communication options were available to participants at their request. The screening process was administered by the central coordinating centre through a central data management system.

RESULTS

Screening activities required staffing of approximately 1.6 full-time equivalents over 4 years. Of 19,022 participants pre-screened, 13,108 attended a third-party pathology collection centre for laboratory screening, 1217 received final, on-site screening, and 1007 were randomised. In total, 95% of the participants opted for online pre-screening over phone-based pre-screening. Screening costs, including both direct and staffing costs, totalled AUD1,420,909 (AUD75 per subject screened and AUD1411 per randomised participant).

CONCLUSION

A multi-step, semi-automated screening process with web-based pre-screening facilitated low-cost, high-volume participant enrolment to this large, multicentre randomised controlled trial. Centralisation and automation of screening activities resulted in substantial savings compared to previous, similar studies. Our screening approach could be adapted to other randomised controlled trial settings to minimise the cost of screening large numbers of participants.

Recruitment of men to a multi-centre diabetes prevention trial: an evaluation of traditional and online promotional strategies

Background

Effective interventions are required to prevent the current rapid increase in the prevalence of Type 2 diabetes. Clinical trials of large-scale interventions to prevent Type 2 diabetes are essential but recruitment is challenging and expensive, and there are limited data regarding the most cost-effective and efficient approaches to recruitment. This paper aims to evaluate the cost and effectiveness of a range of promotional strategies used to recruit men to a large Type 2 diabetes prevention trial.

Methods

An observational study was conducted nested within the Testosterone for the Prevention of Type 2 Diabetes (T4DM) study, a large, multi-centre randomised controlled trial (RCT) of testosterone treatment for the prevention of Type 2 diabetes in men aged 50–74 years at high risk of developing diabetes. Study participation was promoted via mainstream media—television, newspaper and radio; direct marketing using mass mail-outs, publicly displayed posters and attendance at local events; digital platforms, including Facebook and Google; and online promotions by community organisations and businesses. For each strategy, the resulting number of participants and the direct cost involved were recorded. The staff effort required for each strategy was estimated based on feedback from staff.

Results

Of 19,022 men screened for the study, 1007 (5%) were enrolled. The most effective recruitment strategies were targeted radio advertising (accounting for 42% of participants), television news coverage (20%) and mass mail-outs (17%). Other strategies, including radio news, publicly displayed posters, attendance at local events, newspaper advertising, online promotions and Google and Facebook advertising, each accounted for no more than 4% of enrolled participants. Recruitment promotions cost an average of AU$594 per randomised participant. The most cost-effective paid strategy was mass mail-outs by a government health agency (AU$745 per participant). Other paid strategies were more expensive: mail-out by general practitioners (GPs) (AU$1104 per participant), radio advertising (AU$1081) and newspaper advertising (AU$1941).

Conclusion

Radio advertising, television news coverage and mass mail-outs by a government health agency were the most effective recruitment strategies. Close monitoring of recruitment outcomes and ongoing enhancement of recruitment activities played a central role in recruitment to this RCT.

Trial registration

ANZCTR, ID: ACTRN12612000287831. Registered on 12 March 2012.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3485-2) contains supplementary material, which is available to authorized users.

Acute myeloid leukaemia presenting with diabetes insipidus

A 41-year-old man was diagnosed with hypogonadotropic hypogonadism managed with gonadotropins after routine fertility review. Eight months later he presented with new polydipsia and polyuria, lethargy and easy bruising. A full blood count showed 28% circulating blasts. A bone marrow biopsy confirmed a diagnosis of acute myeloid leukaemia with inv(3)(q21.3q26.2) with additional monosomy 7. Central diabetes insipidus (DI) was diagnosed following a water deprivation test. Pituitary magnetic resonance imaging showed a slightly thickened pituitary stalk, stable Rathke's cyst, and new absence of the pituitary bright spot. The patient was commenced on desmopressin and induction chemotherapy, subsequently requiring a bone marrow transplant. Bone marrow examination at 100 days post-transplant revealed cytogenetic remission. All symptoms of DI resolved and magnetic resonance imaging showed return of the posterior bright spot and a pituitary stalk of normal thickness. Biochemical hypogonadotropic hypogonadism persisted but was uninterpretable in the context of systemic illness and recent chemotherapy. DI is a rare complication of haematological malignancies, and the prevalence and pathophysiology of DI in this context are poorly understood. Pathogenic mechanisms proposed include leukaemic infiltration of the pituitary, interference with antidiuretic hormone synthesis, and abnormal thrombopoiesis influencing hormone levels. Particular cytogenetic abnormalities such as inv(3)(q21.3q26.2) and monosomy 7 appear to be more commonly associated with DI and also appear to confer worse outcomes. Aetiologies in the literature remain elusive but as DI is a recognised association of haematological malignancies it should be considered in a patient presenting with polydipsia and polyuria.

Decrease in semen quality and Leydig cell function in infertile men: a longitudinal study

STUDY QUESTION

Are infertile men with reduced semen quality at risk of a further decrease in testicular function?

SUMMARY ANSWER

Infertile men with severely reduced semen quality risk further deterioration of semen quality 15 years after treatment for infertility, and a lower baseline sperm concentration was associated with a more pronounced increase in LH and decrease in testosterone/LH ratio at follow-up.

WHAT IS KNOWN ALREADY

Male factors account for up to 50% of human infertility. The most common finding is spermatogenic failure (SgF) yet the life course of semen quality and testosterone production in such men has not been described.

STUDY DESIGN, SIZE, DURATION

A follow-up study of men with SgF was performed 15 years after the initial infertility assessment between January 1995 and December 2000.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Hospital records were used to identify potential participants in the study. A total of 137 men with primary male infertility due to SgF and 70 controls with good semen quality from couples with female factor infertility who attended a tertiary referral centre were included: the participation rate was 31% and 26%, respectively. The men provided semen samples and underwent a physical examination. Blood samples were taken to measure levels of reproductive hormones (FSH, LH, testosterone, sex hormone-binding globulin, estradiol and inhibin B). Current results were compared with results from the initial assessments.

MAIN RESULTS AND THE ROLE OF CHANCE

At the time of follow up the SgF men had significantly lower Leydig cell capacity than the control group as well as much lower semen quality. For the SgF men, between baseline sampling and follow up, the median sperm concentration decreased from 1.9 to 0.6 mill/ml and total sperm count from 7.7 to 2.0 million (P = 0.019 and 0.012, respectively), and 10% developed azoospermia. Calculated free testosterone (cFT), but not total testosterone (tT) decreased in the SgF group by ~0.6% (95% CI 0.1-1.2%) per year. In the SgF group, LH increased by 1.6% (CI 0.9-2.3%) annually, and consequently tT/LH and cFT/LH ratios had decreased by 1.3% (CI 0.5-2.1) and 2.1% (CI 1.2-3.0%), respectively. The increase in LH and the decreases in tT/LH and cFT/LH ratios were more pronounced in men with lower baseline sperm concentrations.

LIMITATIONS, REASONS FOR CAUTION

We consider the case group as representative of infertile men not in need of testosterone treatment at baseline investigation, but do not have information on those that chose not to participate in the follow-up study. There were alterations in some hormone analysis methods during the follow-up period that may introduce uncertainty in interpretation of long-term changes in hormone levels despite rigorous quality control. The validity of the control group suffers from a lack of hormone values at baseline. Also, at follow-up, for practical reasons only one semen sample could be obtained, which makes the effect estimate more uncertain and there is a risk of non-differential misclassification.

WIDER IMPLICATIONS OF THE FINDINGS

Without being able to predict individual outcomes, it is prudent to consider sperm cryopreservation or advise not to postpone fertility treatment when men present with infertility due to impaired semen quality. Whether partly compensated Leydig cell insufficiency in men with SgF will eventually develop into overt testosterone deficiency cannot be determined from our study.

STUDY FUNDING/COMPETING INTEREST(s)

Aase and Einar Danielsen (Grant no. 10-001053), Nordic Research Committee (Grant no. 5109), The Kirsten and Freddie Johansen Fund, and Rigshospitalet's Research Fund (grant no. R24-A812). There are no competing interests.

Telephone call reminders did not increase screening uptake more than SMS reminders: a recruitment study within a trial

OBJECTIVES

The aim of the study was to compare the response rates and costs of phone call vs. short message service (SMS) screening reminders to prospective randomized controlled trial (RCT) participants.

STUDY DESIGN AND SETTING

This study was a randomized evaluation within a large Australian diabetes prevention RCT. Participants were men aged 50-74 years, overweight or obese, without a previous type 2 diabetes diagnosis. Those eligible on a prescreening questionnaire who did not attend a further screening assessment within 4 weeks were randomized to receive an SMS or phone call reminder (N = 709). The primary outcome was attendance for further screening assessment within 8 weeks of prescreening.

RESULTS

Attendance was 18% (62/354) in the SMS reminder group, and 23% (80/355) in the phone reminder group, with no statistically significant difference in response according to reminder type (relative risk = 1.29, 95% confidence interval [CI]: 0.96-1.73, P = 0.09). The lower confidence limits for response to SMS (95% CI: 14-22%) and phone reminders (95% CI: 18-27%) did not include the 8-week attendance rate before this evaluation, 12%. Phone reminders cost substantially more than SMS reminders (AU$6.21 vs. AU$0.53 per reminder).

CONCLUSION

SMS reminders were as adequate a method as phone reminders to boost RCT screening uptake and were considerably more affordable.

SUN-228 Opioid Use Is Not Associated with Clinical Hypogonadism in Men with Chronic Non-Cancer Pain

Introduction: Opioid analgesia is widely used in the management of chronic pain despite lacking a strong evidence base of efficacy and concerns about adverse effects. Opioid use has been associated with hypogonadotrophic hypogonadism in a limited number of small chronic pain studies. Aim: To determine the prevalence and degree of hypogonadism in men with chronic non-malignant pain treated with or without opioid analgesia. Method: A cross-sectional study of community dwelling Australian men over the age of 18yrs with chronic non-cancer pain of at least 6 months duration attending a single multidisciplinary pain clinic between February 2016 to August 2017, and who were managed either with or without opioid therapy for a minimum of 6 weeks. Men with known pituitary or testicular causes of hypogonadism, previous or current testosterone use, and men treated with androgen deprivation therapy were excluded. Men completed questionnaires about sexual function (International Index of Erectile Function-5), pain (Brief Pain Inventory (BPI)) and mood (Depression, Anxiety and Stress Scale (DASS21)). Medications, age and BMI were recorded. Blood was obtained to assess serum total testosterone (TT), FSH, LH and prolactin (mean ± SD) between the two groups. TT levels were measured using gold standard liquid chromatography-tandem mass spectrometry. Results: Participants were 50 men treated with oral or transdermal opioids (oral morphine equivalent daily dose (oMEDD) 100 ± 92mg) and 37 men managed without opioids. Age (48.8 ± 11.5 vs 51 ± 16.3 yrs) and BMI (28.7 ± 5.0 vs 27.8 ± 4.5) were similar. Mean serum TT levels were within the normal range for both groups although were lower in the opioid vs non-opioid group (13.3 ± 6.1 vs 15.9 ± 5.5 nmol/L [383 ± 175.6 vs 457.9 ± 158.4 ng/dL], p=0.04). TT was < 8nmol/L [<230 ng/dL] in 9/50 men from the opioid group and 3/37 men from the non-opioid group. TT was negatively correlated with BMI in both groups. There was no difference in the opioid vs non-opioid treated men in serum FSH (6.6 ± 3.5 vs 6.3 ± 3.2 IU/L, p=0.63), LH (4.0 ± 2.2 vs 4.8 ± 1.9 IU/L, p=0.06) or prolactin (193 ± 97 vs 178 ± 98 mIU/L, p=0.48). TT levels did not correlate with oMEDD across the group nor in the subset of men (n=17) on oMEDD > 100mg per day. Sexual function scores were similar between the groups and did not correlate with TT. Men taking opioids reported higher severity and intensity of pain (BPI), and higher anxiety, depression and stress levels (DASS21). Discussion: There was no clinically significant association between opioid use or dose and TT in this cohort of men with chronic non-cancer pain. Previous smaller studies of men with chronic non-cancer pain documenting lower testosterone levels have utilised significantly higher oMEDD suggesting a possible threshold dose effect. Although opioid use may contribute to hypogonadism in some men, this should not preclude endocrine evaluation to identify other causes.

Testosterone therapy to prevent type 2 diabetes mellitus in at-risk men (T4DM): Design and implementation of a double-blind randomized controlled trial

BACKGROUND

Low circulating testosterone is associated with an increased risk of developing type 2 diabetes (T2DM) in overweight men with impaired glucose tolerance (IGT).

AIMS

To determine in a multi-centre, double-blinded placebo-controlled randomized trial whether testosterone treatment combined with lifestyle intervention (Weight Watchers) relative to lifestyle intervention alone reduces T2DM incidence and improves glucose tolerance at 2 years.

STUDY POPULATION

Overweight or obese men aged 50-74 years with a serum testosterone of ≤14 nmol/L and IGT or newly diagnosed T2DM established by an oral glucose tolerance test (OGTT).

SETTING, DRUG AND PROTOCOL

Six Australian capital city-based tertiary care centres. Participants were randomized 1:1 and injected with testosterone undecanoate (1000 mg/4 mL) or vehicle (4 mL castor oil), at baseline, 6 weeks and 3-monthly thereafter. PRIMARY ENDPOINTS: (a) Proportion of participants with 2-hour OGTT ≥11.1 mmol/L at 2 years, and (b) a difference at 2 years ≥0.6 mmol/L in the mean 2-hour OGTT glucose between treatments.

SECONDARY ENDPOINTS

Fasting insulin, HbA1c, body composition, maximal handgrip strength; sexual function and lower urinary tract symptoms; serum sex steroids and sex hormone binding globulin; mood and psychosocial function; adherence to lifestyle intervention; and healthcare utilization and costs.

SAFETY

Overseen by an Independent Data Safety Monitoring Committee. Haematocrit, lipids and prostate-specific antigen (PSA) are assessed 6-monthly and information relating to haematological, urological and cardiovascular adverse events from each clinic visit. SUB-STUDIES: (a) Changes in bone density and micro-architecture, (b) motivation and behaviour, (c) telomere length, (d) extended treatment up to 4 years, and (e) hypothalamo-pituitary testicular axis recovery at treatment end.

Associations between major dietary patterns and testicular function in a population-based cohort of young men: results from the Western Australian Pregnancy Cohort (Raine) Study

BACKGROUND

Controversial speculation suggestions that dietary intake may affect semen quality and testicular function, however, there are limited comprehensive studies observing dietary patterns.

OBJECTIVE

To study associations between major dietary patterns and markers of testicular function in adulthood.

MATERIAL AND METHODS

Observational cross-sectional study of two hundred and ninety men with an average age of 20 years, from the Western Australian Pregnancy Cohort (Raine) Study. Usual dietary intake assessed using a semi-quantitative food frequency questionnaire at 20 years of age. Two dietary patterns previously identified using exploratory factor analysis ("Healthy" or "Western") and participants received z-scores for each dietary pattern. Primary endpoints were testicular volume, total sperm per ejaculate, morning serum testosterone concentration. Secondary endpoints were semen sample parameters, inhibin B and sex steroids (DHT: 3α-diol, 3β-diol; LH; FSH; DHEA; estradiol; estrone).

RESULT(S)

Participants were on average 20.0 ± 0.4 years old, had a median of 2 days sexual abstinence and a body mass index of 24.1 ± 3.9 kg/m² , 13% were smokers, 52% were 'moderate' alcohol drinkers, 23% frequently used recreational drugs and 68% reported 'high' physical activity levels. Sperm concentration and DHT 3α-diol were negatively associated with a greater z-score for the "Western" dietary pattern (p = 0.007 and; p = 0.044, respectively), and serum estradiol concentration was positively associated with a "Western" dietary pattern (p = 0.007) after adjustment for BMI, varicocele, cryptorchidism and sexual abstinence.

DISCUSSION

Despite associations between greater intake of the "Western" dietary pattern and a decreased male reproductive health markers, our lack of consistent associations of either a "Healthy" or a "Western" dietary pattern, limit clinical or biological significance in isolation.

CONCLUSIONS

A potential negative association of a "Western" dietary pattern with male reproductive health was detected and should be studied further in population-based studies.

Testosterone therapy to prevent type 2 diabetes mellitus in at-risk men (T4DM): Design and implementation of a double-blind randomized controlled trial

BACKGROUND

Low circulating testosterone is associated with an increased risk of developing type 2 diabetes (T2DM) in overweight men with impaired glucose tolerance (IGT).

AIMS

To determine in a multi-centre, double-blinded placebo-controlled randomized trial whether testosterone treatment combined with lifestyle intervention (Weight Watchers) relative to lifestyle intervention alone reduces T2DM incidence and improves glucose tolerance at 2 years.

STUDY POPULATION

Overweight or obese men aged 50-74 years with a serum testosterone of ≤14 nmol/L and IGT or newly diagnosed T2DM established by an oral glucose tolerance test (OGTT).

SETTING, DRUG AND PROTOCOL

Six Australian capital city-based tertiary care centres. Participants were randomized 1:1 and injected with testosterone undecanoate (1000 mg/4 mL) or vehicle (4 mL castor oil), at baseline, 6 weeks and 3-monthly thereafter. PRIMARY ENDPOINTS: (a) Proportion of participants with 2-hour OGTT ≥11.1 mmol/L at 2 years, and (b) a difference at 2 years ≥0.6 mmol/L in the mean 2-hour OGTT glucose between treatments.

SECONDARY ENDPOINTS

Fasting insulin, HbA1c, body composition, maximal handgrip strength; sexual function and lower urinary tract symptoms; serum sex steroids and sex hormone binding globulin; mood and psychosocial function; adherence to lifestyle intervention; and healthcare utilization and costs.

SAFETY

Overseen by an Independent Data Safety Monitoring Committee. Haematocrit, lipids and prostate-specific antigen (PSA) are assessed 6-monthly and information relating to haematological, urological and cardiovascular adverse events from each clinic visit. SUB-STUDIES: (a) Changes in bone density and micro-architecture, (b) motivation and behaviour, (c) telomere length, (d) extended treatment up to 4 years, and (e) hypothalamo-pituitary testicular axis recovery at treatment end.

Gonadal Hormones in the Pathogenesis and Treatment of Bone Health in Patients with Chronic Kidney Disease: a Systematic Review and Meta-Analysis

PURPOSE OF REVIEW

Patients with chronic kidney disease (CKD) have a greatly increased fracture risk compared with the general population. Gonadal hormones have an important influence on bone mineral density (BMD) and fracture risk, and hormone therapies can significantly improve these outcomes. Gonadal dysfunction is a frequent finding in patients with CKD; yet, little is known about the impact of gonadal hormones in the pathogenesis and treatment of bone health in patients with CKD. This systematic review and meta-analysis aimed to examine the effects of gonadal hormones and hormone therapies on bone outcomes in men and women with CKD.

METHODS

EMBASE, MEDLINE, SCOPUS, and clinical trial registries were systematically searched from inception to February 14, 2018 for studies that assessed gonadal hormones or hormone treatments with bone outcomes in patients with CKD stage 3-5D. Two independent reviewers screened the titles and abstracts of search results according to inclusion criteria and assessed study quality and risk of bias using validated assessment tools.

RECENT FINDINGS

Thirteen studies met the inclusion criteria. Six moderate-to-high quality observational studies showed inconsistent association between any gonadal hormone and bone outcomes, limited by significant study heterogeneity. Five moderate-high risk of bias interventional studies examined treatment with selective oestrogen receptor modulators in post-menopausal women (four using raloxifene and one bazedoxifene) and demonstrated variable effects on BMD and fracture outcomes. Meta-analysis of raloxifene treatment in post-menopausal women demonstrated improvement in lumbar spine (SMD 3.30; 95% CI 3.21-3.38) and femoral neck (SMD 3.29; 95% CI 3.21-3.36) BMD compared with placebo. Transdermal oestradiol/norethisterone in pre-menopausal women receiving dialysis (n = 1 study), demonstrated BMD improvement over 12 months. Testosterone treatment for 6 months in dialysis-dependant men (n = 1 study) did not improve BMD. There is evidence that raloxifene treatment may be beneficial in improving BMD in post-menopausal women with CKD. There is insufficient evidence for other hormone treatments in men or women. Despite high fracture rates and frequent gonadal dysfunction in patients with CKD, significant evidence gaps exist, and well-designed studies are required to specifically assess the impact of gonadal status in the pathogenesis of CKD-related bone fragility and its treatment.

The Possible Impact of Antenatal Exposure to Ubiquitous Phthalates Upon Male Reproductive Function at 20 Years of Age

Phthalates are ubiquitous environmental endocrine-disrupting chemicals suspected to interfere with developmental androgen action leading to adverse effects on male reproductive function. Prenatal exposure studies in rodents show cryptorchidism, hypospadias and reduced testicular volume (TV), testosterone and anogenital distance in males. It is postulated that there is a developmental window in utero when phthalate exposure has the most potent adverse effects. Some human studies show associations between prenatal phthalate exposure and reduced calculated "free" serum testosterone in infant boys and shorter anogenital distance. However, there are no data available yet which link antenatal exposure to long-term effects in men. We aimed to correlate antenatal phthalate exposure with adult TV, semen parameters and serum reproductive hormone concentrations. 913 men from the Western Australian (Raine) Pregnancy Cohort were contacted aged 20-22 years. 423 (56%) agreed to participate; 404 underwent testicular ultrasound examination; 365 provided semen samples, and reproductive hormones were measured in 384. Maternal antenatal serum phthalate metabolite measurements were available for 185 and 111 men, who provided serum and semen, respectively. Maternal serum collected at 18 and 34 weeks gestation, stored at -80°C, was pooled and analyzed for 32 phthalate metabolites by liquid chromatography-tandem mass spectrometry. TV was calculated, semen analysis performed by WHO approved methods, and serum concentrations of gonadotrophins, inhibin B, and testosterone measured. Eleven phthalate metabolites were detected. Primary and secondary metabolites of di-(2-ethyl-hexyl) phthalate (DEHP) and di-iso-nonyl phthalate (DiNP) were positively correlated. After correction for adult height, BMI, presence of a varicocele and exposure to maternal smoking mono-iso-nonyl phthalate (MiNP) (r = -0.22) and sums of DEHP and DiNP metabolites (r = -0.24) and the sum of the metabolites of the high molecular weight phthalates (r = -0.21) were negatively correlated with TV (all p < 0.05). After adjustment for BMI adult serum total testosterone was positively associated with exposure to the following antenatal serum phthalate metabolites: mono-(2-ethylhexyl) phthalate (r = 0.26), MiNP (r = 0.18), the sum of metabolites for DEHP (r = 0.21) and DiNP (r = 0.18), and the sum of high molecular phthalates (r = 0.20) (p = 0.0005 to p = 0.02). Given sample size, storage duration and confounding through postnatal exposures, further studies are required.

The impact of antenatal Bisphenol A exposure on male reproductive function at 20-22 years of age

Bisphenol A (BPA) is a ubiquitous chemical suspected to possess oestrogenic hormonal activities. Male population studies suggest a negative impact on testicular function. As Sertoli cell proliferation occurs during fetal or early postnatal life, it is speculated that oestrogenic environmental exposures may influence mature testicular function. Among 705 Western Australian Pregnancy Cohort (Raine) Study men aged 20-22 years, 404 underwent testicular ultrasound examination (149 had maternal serum available), and/or 365 provided semen (136 had maternal serum) and/or 609 serum samples for sex steroids, gonadotrophins and inhibin B analysis (244 had maternal serum). Maternal serum collected at 18 and 34 weeks' gestation was pooled and assayed for concentrations of total BPA (free plus conjugated) as an estimate of antenatal exposure. Testicular volume was calculated by ultrasonography, and semen analysis performed. Serum LH, FSH and inhibin B were measured by immunoassay; testosterone, oestradiol, oestrone andBPA were measured by liquid chromatography-mass spectrometry. BPA levels were detectable in most (89%) maternal serum samples. After adjustment for maternal smoking, abstinence and varicocele, sperm concentration and motility were significantly correlated to maternal serum BPA (r = 0.18; P = 0.04 for both). No other associations of maternal serum BPA with testicular function were observed.

The diagnosis of male infertility: an analysis of the evidence to support the development of global WHO guidance-challenges and future research opportunities

BACKGROUND

Herein, we describe the consensus guideline methodology, summarize the evidence-based recommendations we provided to the World Health Organization (WHO) for their consideration in the development of global guidance and present a narrative review of the diagnosis of male infertility as related to the eight prioritized (problem or population (P), intervention (I), comparison (C) and outcome(s) (O) (PICO)) questions. Additionally, we discuss the challenges and research gaps identified during the synthesis of this evidence.

OBJECTIVE AND RATIONALE

The aim of this paper is to present an evidence-based approach for the diagnosis of male infertility as related to the eight prioritized PICO questions.

SEARCH METHODS

Collating the evidence to support providing recommendations involved a collaborative process as developed by WHO, namely: identification of priority questions and critical outcomes; retrieval of up-to-date evidence and existing guidelines; assessment and synthesis of the evidence; and the formulation of draft recommendations to be used for reaching consensus with a wide range of global stakeholders. For each draft recommendation the quality of the supporting evidence was then graded and assessed for consideration during a WHO consensus.

OUTCOMES

Evidence was synthesized and recommendations were drafted to address the diagnosis of male infertility specifically encompassing the following: What is the prevalence of male infertility and what proportion of infertility is attributable to the male? Is it necessary for all infertile men to undergo a thorough evaluation? What is the clinical (ART/non ART) value of traditional semen parameters? What key male lifestyle factors impact on fertility (focusing on obesity, heat and tobacco smoking)? Do supplementary oral antioxidants or herbal therapies significantly influence fertility outcomes for infertile men? What are the evidence-based criteria for genetic screening of infertile men? How does a history of neoplasia and related treatments in the male impact on (his and his partner's) reproductive health and fertility options? And lastly, what is the impact of varicocele on male fertility and does correction of varicocele improve semen parameters and/or fertility?

WIDER IMPLICATIONS

This evidence synthesis analysis has been conducted in a manner to be considered for global applicability for the diagnosis of male infertility.

Men's knowledge, attitudes and behaviours relating to fertility

BACKGROUND

The increasingly common practice in high-income countries to delay childbearing to the fourth and fifth decades of life increases the risk of involuntary childlessness or having fewer children than desired. Older age also increases the risk of age-related infertility, the need for ART to conceive, and obstetric and neonatal complications. Existing research relating to childbearing focusses almost exclusively on women, and in public discourse declining fertility rates are often assumed to be the result of women delaying childbearing to pursue other life goals such as a career and travel. However, evidence suggests that the lack of a partner or a partner willing to commit to parenthood is the main reason for later childbearing.

OBJECTIVE AND RATIONALE

To better understand men's contributions to childbearing decisions and outcomes, the literature pertaining to men's fertility-related knowledge, attitudes and behaviours was reviewed.

SEARCH METHODS

The electronic databases of Medline, Embase and PsycINFO were searched to identify investigations of men's knowledge, attitudes and behaviours relating to fertility, infertility, reproductive health or childbearing using relevant fertility keyword search terms. Studies were included if they had investigated factors associated with men's fertility-related knowledge, attitudes and behaviours, had been conducted in a high-income country and were published in an English language peer-reviewed journal between January 2005 and August 2016.

OUTCOMES

The search yielded 1349 citations. Of these, 47 papers representing 43 unique studies were included in the review. Where response rate was reported, it ranged between 13 and 94%. Studies varied in terms of research design; inclusion and exclusion criteria; recruitment strategies; adequacy of sample size; recruitment and retention rates and data collection tools. However, findings were consistent and indicate that men almost universally value parenthood, want and expect to become fathers, and aspire to have at least two children. Yet most men have inadequate knowledge about the limitations of female and male fertility and overestimate the chance of spontaneous and assisted conception. Perceptions of ideal circumstances in which to have children included being in a stable and loving relationship, having completed studies, secured a permanent job and a dependable income, having achieved personal maturity, and having a partner who desires children and is 'suitable' as a potential co-parent. Although all studies were conducted in high-income countries, between-country social and cultural differences may have influenced the findings relating to attitudes.

WIDER IMPLICATIONS

Men aspire to parenthood as much as women do but have limited knowledge about the factors that influence fertility. The gap between ideal biological and ideal social age for having children appears to be widening, narrowing the time frame in which parenthood can be achieved. This may lead to unfulfilled parenthood aspirations. The findings can inform government policies and public education strategies aimed to support childbearing during the most fertile years, reduce the personal and societal cost of infertility and ART use, and allow people to fulfil their parenthood goals.

Clinical review of 24-35 year olds conceived with and without in vitro fertilization: study protocol

Background

Children conceived by assisted reproductive technologies (ART) currently comprise 4% of Australian births. The manipulation of biological parameters related to fertilization and implantation are integral to successful ART but potentially pose a risk to the longer-term health of the offspring. There is consensus that many common adult health problems (particularly cardiovascular, metabolic and respiratory conditions) have their origins in early life, possibly before birth, and that risk trajectories track through childhood until clinical disease manifests in adulthood. Early life epigenetic variation may play a role in this process. However little is known about the long-term health of individuals conceived by ART. In a previous study, based on telephone-interviews, we found that young adults conceived by in vitro fertilization (IVF) had significantly more maternal reported atopic respiratory, endocrine, nutritional, and metabolic conditions than non-IVF conceived matched controls. Here we outline the protocol for a follow-up biomedical assessment of this cohort and a questionnaire to obtain information on potential confounders.

Methods

We are conducting a clinical review of an existing, well characterised cohort comprising 547 IVF-conceived adults and 549 matched controls. We are measuring cardiovascular intermediate phenotypes, metabolic parameters and respiratory function, complemented by epigenome-wide DNA methylation analysis. A pilot study demonstrated the feasibility of our proposed protocol and its acceptability to participants. Participants attend a 2–3 h clinical assessment and complete a study-specific online questionnaire. Measurements include: 1) cardiovascular phenotypes: carotid artery intima-media thickness and distensibility, retinal vascular calibre, resting blood pressure, pulse wave velocity and pulse wave analysis; 2) respiratory function: spirometry, plethysmography, multiple breath washout; 3) auxology: height, weight, waist circumference, bio-impedance. Blood is collected for 4) biomarkers of cardiometabolic profile including inflammatory markers and 5) epigenetic analysis.

Discussion

Recruitment for this clinical review is challenging as many of the participants have moved to regional, interstate or international locations. Additionally, many female participants are pregnant or breastfeeding, and are therefore ineligible. Nevertheless, comprehensive strategies have been developed to optimize recruitment. Given the increasing use of IVF and related technologies, the potential long-term consequences for risk of common adult diseases is an important clinical and public health issue.

Serum phosphorus levels and fracture following renal transplantation

PURPOSE

Increased fracture rates are observed in renal transplant recipients (RTRs) compared with the general population. Risk factors include age, diabetes, dialysis vintage, immunosuppression and mineral and bone disorders.¹ Low serum phosphorus levels occur post-transplantation; however, its relationship with fracture risk has not been evaluated. The purpose of this study was to evaluate risk factors for fracture in RTRs at a single tertiary referral centre.

METHODS

A retrospective cross-sectional analysis of 146 patients (75 M, 71 F) who had been referred for dual energy X-ray densitometry (DXA) post-renal transplantation was performed. Aetiology of end stage kidney disease (ESKD), duration of dialysis, parathyroidectomy history, immunosuppression regimen, bone mineral density (BMD), biochemistry and fractures were documented. Statistical analyses included univariable and multivariable regression.

RESULTS

The mean age of patients was 54 years and mean time post-transplantation 6.7 years. A total of 79 fractures occurred in 52 patients (35%), with 40 fractures occurring post-transplantation. Ankle/foot fractures were most common (48%). Lower serum phosphorus levels and declining femoral neck (FN) T-score and were associated with fractures in both univariable and multivariable regression analyses after adjusting for age, gender, weight, estimated glomerular filtration rate and pre-transplant history of fracture (P=.011 and P=.042 respectively). The relationship between serum phosphorus and fracture remained significant independent of FN T-score, parathyroid hormone levels, parathyroidectomy status and prednisolone use.

CONCLUSION

Fracture was common post-renal transplantation. Lower serum phosphorus levels and declining FN T-scores were associated with fractures. The mechanism of this previously unreported observation requires further evaluation in prospective studies.

Development of a health promotion programme to improve awareness of factors that affect fertility, and evaluation of its reach in the first 5 years

Awareness among people of reproductive age about the factors that influence fertility and reproductive outcomes, including medically assisted reproduction outcomes, is generally low. To improve awareness about the potentially modifiable factors that affect fertility and reproductive outcomes, 'Your Fertility', a fertility health promotion programme funded by the Australian Government, was established in 2011. This paper describes the development and evaluation of the reach of the Your Fertility programme from its inception in 2011 to June 2016. Systematically recorded outcomes for the programme's key focus areas and Google Analytics data were collated. Key achievements include developing and maintaining an internationally renowned website that experiences high growth and demand for fertility-related information; by 2016, over 5 million users had viewed more than 10 million webpages, and over 96,000 users had engaged in programme messages across social media. Programme messages have reached more than 4 million Australian social media users, and a potential audience of 150 million through media coverage across more than 320 media features. More than 4200 education and health professionals have completed online learning modules, and external partnerships have been established with 14 separate organizations. Data collected over 5 years indicate that the Your Fertility programme meets a need for targeted, evidence-based, accessible fertility-related information.

Socio-economic disparities in access to assisted reproductive technologies in Australia

Women from disadvantaged socio-economic groups access assisted reproductive technology treatment less than women from more advantaged groups. However, women from disadvantaged groups tend to start families younger, making them less likely to suffer from age-related subfertility and potentially have less need for fertility treatment. Whether socio-economic disparities in access to assisted reproductive technology treatment persist after controlling for the need for treatment, has not been previously explored. This population based study demonstrates that socio-economic disparities in access to assisted reproductive technology treatment persist after adjusting for several confounding factors, including age at first birth (used as a measure of delayed childbearing, hence a proxy for need for fertility treatment), geographic remoteness and Australian jurisdiction. Assisted reproductive technology access progressively decreased as socio-economic quintiles became more disadvantaged, with a 15.8% decrease in access in the most disadvantaged quintile compared with the most advantaged quintile after controlling for confounding factors. The adjusted rate of access to assisted reproductive technology treatment also decreased by 12.3% for women living in regional and remote areas compared with those in major cities. These findings indicate that financial and sociocultural barriers to assisted reproductive technology treatment remain in disadvantaged groups after adjusting for need.

Comparing indicators of health and development of singleton young adults conceived with and without assisted reproductive technology

OBJECTIVE

To compare outcomes for young adults conceived by assisted reproductive technology (ART) with non-ART-conceived young adults.

DESIGN

Cohort study.

SETTING

Not applicable.

PARTICIPANT(S)

Mothers and their offspring (aged 18-28 years) conceived by ART; mothers and their non-ART-conceived offspring, randomly selected from the same source population.

INTERVENTION(S)

Structured telephone interviews, one with mothers and another with their young adult offspring.

MAIN OUTCOME MEASURE(S)

Maternal report on young adult offspring hospitalizations and chronic illness accumulated over the first 18 years of their lives; young adult self-report on perceived current quality of life, body mass index, pubertal development, and educational achievement.

RESULT(S)

Of 1,480 eligible ART mothers, 80% were traced and contacted. Of those, 656 (55%) participated, reporting on 705 ART-conceived offspring; 269 (23%) declined participation and 262 (22%) did not respond. Of the participants, 84% consented to contact with their young adult offspring, of whom 547 (92%) participated. Random-digit dialing recruited 868 non-ART mothers and 549 offspring. Compared with non-ART young adults, the ART group had significant increases in three maternally reported outcomes: 1) hospital admissions, including those in the secondary school years; 2) atopic respiratory conditions; and 3) combined endocrine, nutritional, and metabolic disease ICD-10 category. Young adult reported outcomes were similar for both groups.

CONCLUSION(S)

This study addresses gaps in knowledge of outcomes beyond adolescence for those conceived by ART. Results show few adverse outcomes in this large cohort of young adults, but additional assessment through clinical review is required to address issues unable to be examined in this study.

Performance of direct estradiol immunoassays with human male serum samples

BACKGROUND

Steroid immunoassays originally required solvent extraction, chromatography, and structurally authentic tracers to avoid interference from steroid cross-reactivity and matrix effects. The demand for steroid assays has driven assay simplification, bypassing this triplet of validity criteria to allow use of unextracted serum, which has introduced bias and nonspecificity at low steroid concentrations. We aimed to evaluate the performance of commercial direct estradiol (E2) immunoassays relative to the reference method of LC-MS and compared serum E2 measurements from each assay with biomarkers of estrogen action.

METHODS

We measured serum E2 in duplicate using 5 commercial direct immunoassays and LC-MS in a nested cohort of 101 healthy, asymptomatic men >40 years old from the Healthy Man Study. For each immunoassay, we evaluated the detectability and distribution of serum E2 measurements, CV, and bias (relative to LC-MS) by Passing-Bablok regression and deviance plots.

RESULTS

Three assays detected E2 in all samples, whereas E2 was detected in only 53% and 72% of samples by 2 other assays. All 5 assays had positive biases, ranging from 6% to 74%, throughout their ranges. CVs were lower with 4 immunoassays than with LC-MS. LC-MS, but none of the direct immunoassays, correlated with serum testosterone and sex steroid-binding globulin.

CONCLUSIONS

The positive bias of direct E2 immunoassays throughout their working range reflects the nonspecific effects of steroid cross-reactivity and/or matrix interference arising from the violation of the triplet validity criteria for steroid immunoassay.

Osteitic bone: a surrogate marker of eosinophilia in chronic rhinosinusitis

BACKGROUND

Causes of osteitis in chronic rhinosinusitis (CRS) other than previous surgery are poorly defined. Patients with eosinophilic CRS (ECRS) have more severe disease and poorer outcomes despite repeated surgery. Associations between osteitis and markers of ECRS are not well described.

METHODS

A cross-sectional study of CRS patients undergoing sinus surgery was conducted. Osteitis was scored radiologically using previously published measures. Associations between osteitis and histopathology, symptoms, endoscopy, CT mucosal score and seromarkers were analyzed.

RESULTS

Eighty-eight patients were assessed of whom forty-five had osteitis. Patients undergoing revision surgery recorded higher osteitis scores. Patients with mucosal eosinophilia had higher osteitis score than those without. Patients with osteitis had higher serum eosinophil. Similar relationships were also found in primary surgery. Osteitis was associated with endoscopic and radiologic, but not symptomatic disease severity.

CONCLUSIONS

Osteitis is associated with tissue and serum eosinophilia in both patients with and without prior surgery. Patients with these features may benefit from post-operative corticosteroid therapy to prevent osteitis.

Supersensitive fluorescent semen analysis: validation on azoospermic and oligozoospermic samples

OBJECTIVE

To compare the clinical utility of a supersensitive fluorescent semen analysis (SSSA) procedure published by Cooper et al. (2006) with a conventional World Health Organization (WHO)-based semen analysis technique in males with severe oligozoospermia or azoospermia who are undergoing fertility assessment.

DESIGN

Prospective single-center study.

SETTING

IVF clinic.

PATIENT(S)

Patients attending an infertility clinic for semen analysis.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Presence of spermatozoa in the ejaculate.

RESULT(S)

Semen samples from 100 men were analyzed using conventional WHO 4th Edition semen analysis and determined to be either severely oligozoospermic or azoospermic (reported lower limit of detection of 0.1 million sperm/mL). An aliquot of the same unprocessed sample was also analyzed using the SSSA protocol (reported lower limit of detection of approximately 8000 sperm/mL). The SSSA method confirmed the results of conventional semen analysis in 77% of cases. In 22% of cases, sperm were identified only using SSSA. Overall, SSSA was capable of identifying the presence of sperm in significantly more samples than conventional semen analysis.

CONCLUSION(S)

The reliable differentiation of extreme oligospermia from azoospermia has profound implications in fertility management. This paper provides the first data comparing sperm detection rates using SSSA or conventional WHO-based approaches in extreme oligozoospermic and azoospermic men in an IVF setting. Results indicate that approximately one in four men classified as azoospermic by conventional semen analysis may actually have sperm present. The improved sensitivity of the SSSA technique may be of significant benefit to patients, particularly in fertility and assisted reproductive technique decision making.

What is new in cryptorchidism and hypospadias--a critical review on the testicular dysgenesis hypothesis

It has been hypothesized that poor semen quality, testis cancer, undescended testis, and hypospadias are symptoms of one underlying entity--the testicular dysgenesis syndrome--leading to increasing male fertility impairment. Though testicular cancer has increased in many Western countries during the past 40 years, hypospadias rates have not changed with certainty over the same period. Also, recent studies demonstrate that sperm output may have declined in certain areas of Europe but is probably not declining across the globe as indicated by American studies. However, at the same time, there is increasing recognition of male infertility related to obesity and smoking. There is no certain evidence that the rates of undescended testes have been increasing with time during the last 50 years. In more than 95% of the cases, hypospadias is not associated with cryptorchidism, suggesting major differences in pathogenesis. Placental abnormality may occasionally cause both cryptorchidism and hypospadias, as it is also the case in many other congenital malformations. The findings of early orchidopexy lowering the risk of both infertility and testicular cancer suggest that the abnormal location exposes the cryptorchid testis to infertility and malignant transformation, rather than there being a primary abnormality. Statistically, 5% of testicular cancers only are caused by cryptorchidism. These data point to the complexity of pathogenic and epidemiologic features of each component and the difficulties in ascribing them to a single unifying process, such as testicular dysgenesis syndrome, particularly when so little is known of the actual mechanisms of disease.

Analysis of activin/TGFB-signaling modulators within the normal and dysfunctional adult human testis reveals evidence of altered signaling capacity in a subset of seminomas

Activin is a pleiotropic growth factor belonging to the transforming growth factor-beta (TGFB) superfamily of signaling molecules. Regulated activin signaling is known to influence several steps in rodent male gamete differentiation. TGFB ligand isoforms, TGFB1-B3, also influence germ cell survival in the rodent testis at the onset of spermatogenesis and around the time of puberty. Given the importance of regulated activin and TGFB signaling in testis development and function, we sought to investigate the cellular production sites of activin/TGFB-signaling modulators in normal and dysfunctional adult human testes samples. Signaling transducers phosphorylated SMAD2/3, and signaling modulators SMAD6, MAN-1, inhibin alpha (INHA), and beta-glycan were detected in Bouins fixed, paraffin-embedded adult human testis sections using immunohistochemistry. Additional samples examined were from testicular cancer patients and from normal men subjected to gonadotropin suppression with androgen-based contraceptives. Our findings identify distinct differences between normal and gonadotropin-deprived human testis in the expression and cellular localization of activin/TGFB-signaling modulators. The presence of a nuclear phosphorylated SMAD2/3 signal in all analyzed seminoma specimens indicated active activin/TGFB signaling. Moreover, a subset of seminoma specimens exhibited selective enhanced expression of beta-glycan (4 out of 28 seminoma tumors), INHA (6 out of 28), and MAN-1 (6 out of 28), highlighting potential functional differences between individual tumors in their capacity to regulate activin/TGFB signaling. Within the heterogenous nonseminomas, expression of signaling modulators was variable and reflected the degree of somatic differentiation. Thus, synthesis of activin and TGFB-signaling modulators may be affected by spermatogenic disruption and altered hormone levels in the testis.

Predictive accuracy and sources of variability in calculated free testosterone estimates

Background

Serum free testosterone (FT) concentrations are commonly requested, but because reference FT methods are too laborious various calculational algorithms for FT based on total testosterone (TT) and sex hormone-binding globulin (SHBG) are frequently used. This study provides the first large-scale evaluation of the predictive accuracy and sources of variability for different FT formulae compared with direct laboratory measurements.

Methods

Using a large data-set of direct FT measurements by centrifugal ultrafiltration, the predictive accuracy of five different formulas for cFT (four existing plus a new formula) is evaluated in 3975 consecutive blood samples. In a second data-set of 124 samples from a reference panel of healthy eugonadal young men, we estimate the relative influence of the five algorithms and eight different TT and two SHBG assays including all available commercial total TT and SHBG assays together with a gas chromatography/mass spectrometry T reference method.

Results

cFT formulae show wide discrepancies with equilibrium-binding algorithms showing systematic overestimation relative to direct FT measurements, whereas two empirical cFT methods were more concordant. Variations between commercially available TT immunoassays have a strong impact on calculation of FT with TT assays contributing 82.2% of overall variance compared with 13.7% for the cFT algorithms and 4.1% for the SHBG assays.

Conclusions

If FT measurements are requested and direct measurement impractical, cFT formulae using TT and SHBG immunoassays provide an approximation to direct FT measurement that is strongly dependent on the TT, cFT formula used and, to a lesser extent, SHBG immunoassays.

Phenotypic variation within European carriers of the Y-chromosomal gr/gr deletion is independent of Y-chromosomal background

BACKGROUND

Previous studies have compared sperm phenotypes between men with partial deletions within the AZFc region of the Y chromosome and non-carriers, with variable results. In this study, a separate question was investigated, the basis of the variation in sperm phenotype within gr/gr deletion carriers, which ranges from normozoospermia to azoospermia. Differences in the genes removed by independent gr/gr deletions, the occurrence of subsequent duplications or the presence of linked modifying variants elsewhere on the chromosome have been suggested as possible causal factors. This study set out to test these possibilities in a large sample of gr/gr deletion carriers with known phenotypes spanning the complete range.

RESULTS

In total, 169 men diagnosed with gr/gr deletions from six centres in Europe and one in Australia were studied. The DAZ and CDY1 copies retained, the presence or absence of duplications and the Y-chromosomal haplogroup were characterised. Although the study had good power to detect factors that accounted for >or=5.5% of the variation in sperm concentration, no such factor was found. A negative effect of gr/gr deletions followed by b2/b4 duplication was found within the normospermic group, which remains to be further explored in a larger study population. Finally, significant geographical differences in the frequency of different subtypes of gr/gr deletions were found, which may have relevance for the interpretation of case control studies dealing with admixed populations.

CONCLUSIONS

The phenotypic variation of gr/gr carriers in men of European origin is largely independent of the Y-chromosomal background.

Activin receptor subunits in normal and dysfunctional adult human testis

BACKGROUND

The cellular sites of activin action and its regulation in the normal and dysfunctional adult human testis are unknown.

METHODS

Activin type I (ALK2 and ALK4) and type II (ActRIIA and ActRIIB) receptors were detected using immunohistochemistry on Bouins fixed sections of normal, carcinoma in situ (CIS), seminoma, non-seminoma and gonadotropin-deprived human testis. ActRIIA mRNA was localized by in situ hybridization.

RESULTS

ALK2, ALK4 and ActRIIB proteins were observed in Sertoli cells, spermatogonia and some spermatocytes within normal and gonadotropin-suppressed adult human testis; all three receptor subunits were also detected in CIS, seminoma and non-seminoma cells. ActRIIA immunoreactivity was faint to absent in the normal testis and in CIS and non-seminoma cells, whereas some seminoma cells displayed a strong signal. Also in contrast to the normal testis, a majority of spermatogonia and Sertoli cells in gonadotropin-deprived samples exhibited a strong ActRIIA immunohistochemical and in situ hybridization signal.

CONCLUSIONS

Spermatogonia and Sertoli cells appear as the primary targets of activin action in the adult human testis. Changes in testicular function associated with altered hormone levels may enhance ActRIIA mRNA and protein synthesis, thus modifying signalling by activin or other TGFbeta ligands within specific cells of the seminiferous epithelium.

A hamiltonian particle method for diffeomorphic image registration

Diffeomorphic image registration, where images are aligned using diffeomorphic warps, is a popular subject for research in medical image analysis. We introduce a novel algorithm for computing diffeomorphic warps that solves the Euler equations on the diffeomorphism group explicitly, based on a discretisation of the Hamiltonian, rather than using an optimiser. The result is an algorithm that is many times faster than those considered previously.

Cancer risks associated with the diagnosis of infertility

The effects of infertility and its treatment on cancer risk are of concern to many infertile couples. Infertile women appear to be at no higher risk for breast cancer although they may be more at risk for cancers of the uterus, particularly if they have ovulation disorders. Most studies show no increase in the risk of invasive ovarian cancer in infertile women, but ovarian tumours of borderline malignancy are more common. There seems to be no overall increase in cancer risk associated with fertility drug treatment, but questions remain about risk in subgroups of infertile women. Male infertility has been associated with an increased risk of testis cancer. Cancer incidence in children born after fertility treatment appears to be similar to that in the general population. Discussion of cancer risks in the context of other reproductive and community risks can be helpful to patients.

The combinatorics of tandem duplication trees

We developed a recurrence relation that counts the number of tandem duplication trees (either rooted or unrooted) that are consistent with a set of n tandemly repeated sequences generated under the standard unequal recombination (or crossover) model of tandem duplications. The number of rooted duplication trees is exactly twice the number of unrooted trees, which means that on average only two positions for a root on a duplication tree are possible. Using the recurrence, we tabulated these numbers for small values of n. We also developed an asymptotic formula that for large n provides estimates for these numbers. These numbers give a priori probabilities for phylogenies of the repeated sequences to be duplication trees. This work extends earlier studies where exhaustive counts of the numbers for small n were obtained. One application showed the significance of finding that most maximum-parsimony trees constructed from repeat sequences from human immunoglobins and T-cell receptors were tandem duplication trees. Those findings provided strong support to the proposed mechanisms of tandem gene duplication. The recurrence relation also suggests efficient algorithms to recognize duplication trees and to generate random duplication trees for simulation. We present a linear-time recognition algorithm.