Unexplained infertility

Sperm DNA fragmentation testing: Summary evidence and clinical practice recommendations

We herein summarise the evidence concerning the impact of sperm DNA fragmentation in various clinical infertility scenarios and the advances on sperm DNA fragmentation tests. The collected evidence was used to formulate 41 recommendations. Of these, 13 recommendations concern technical aspects of sperm DNA fragmentation testing, including pre-analytical information, clinical thresholds and interpretation of results. The remaining 28 recommendations relate to indications for sperm DNA fragmentation testing and clinical management. Clinical scenarios like varicocele, unexplained infertility, idiopathic infertility, recurrent pregnancy loss, intrauterine insemination, in vitro fertilisation/intracytoplasmic sperm injection, fertility counselling for men with infertility risk factors and sperm cryopreservation have been contemplated. The bulk evidence supporting the recommendations has increased in recent years, but it is still of moderate to low quality. This guideline provides clinicians with advice on best practices in sperm DNA fragmentation testing. Also, recommendations are provided on possible management strategies to overcome infertility related to sperm DNA fragmentation, based on the best available evidence. Lastly, we identified gaps in knowledge and opportunities for research and elaborated a list of recommendations to stimulate further investigation.

Utility of Antioxidants in the Treatment of Male Infertility: Clinical Guidelines Based on a Systematic Review and Analysis of Evidence

It is widely accepted that oxidative stress plays an important role in the pathophysiology of male infertility and that antioxidants could have a significant role in the treatment of male infertility. The main objectives of this study are: 1) to systematically review the current evidence for the utility of antioxidants in the treatment of male infertility; and 2) propose evidence-based clinical guidelines for the use of antioxidants in the treatment of male infertility. A systematic review of the available clinical evidence was performed, with articles published on Scopus being manually screened. Data extracted included the type of antioxidant used, the clinical conditions under investigation, the evaluation of semen parameters and reproductive outcomes. The adherence to the Cambridge Quality Checklist, Cochrane Risk of Bias for randomized controlled trials (RCTs), CONSORT guidelines and JADAD score were analyzed for each included study. Further, we provided a Strength Weakness Opportunity Threat (SWOT) analysis to analyze the current and future value of antioxidants in male infertility. Of the 1,978 articles identified, 97 articles were included in the study. Of these, 52 (53.6%) were uncontrolled (open label), 12 (12.4%) unblinded RCTs, and 33 (34.0%) blinded RCTs, whereas 44 (45.4%) articles tested individual antioxidants, 31 (32.0%) a combination of several products in variable dosages, and 22 (22.6%) registered antioxidant products. Based on the published evidence, we 1) critically examined the necessity of additional double-blind, randomized, placebo-controlled trials, and 2) proposed updated evidence-based clinical guidelines for antioxidant therapy in male infertility. The current systematic review on antioxidants and male infertility clearly shows that antioxidant supplementation improves semen parameters. In addition, it provides the indications for antioxidant treatment in specific clinical conditions, including varicocele, unexplained and idiopathic male infertility, as well as in cases of altered semen quality.

Redox potential in human semen: Validation and qualification of the MiOXsys assay

Seminal oxidative stress (OS) is a major contributing factor to male infertility. Semen analysis cannot identify reactive oxygen species (ROS), which can be measured using a chemiluminescence assay. Measurement of redox potential provides a more comprehensive assessment of OS, although the test has yet to be fully validated. This study aimed to validate the MiOX^sys analyser for measuring static oxidation-reduction potential (sORP). Results demonstrated that duplicate measurements must be taken, sensors must be batch tested, and sockets should be regularly changed to avoid inconsistency in measurement. Measurement of sORP using MiOX^sys exhibited good reproducibility across different operators (p = 0.469), analysers (p = 0.963) and days (p = 0.942). It is not affected by mechanical agitation (p = 0.522) or snap freezing and thawing (p = 0.823). The stability of sORP over time requires further verification, particularly in samples with high initial sORP. Measurement is temperature sensitive between 2 and 37°C, significantly increasing with increasing temperature (p = 0.0004). MiOX^sys is a more stable assay for assessing OS than chemiluminescence methods and permits greater flexibility for sample handling. MiOX^sys could be implemented to complement semen analysis as part of routine diagnostic testing for male infertility and may be useful in identifying contributing factors to idiopathic infertility.

Codeine-induced sperm DNA damage is mediated predominantly by oxidative stress rather than apoptosis

ABSTRACTBackground: Opioids have been implicated to induce infertility. Although codeine remains the most used opioid for recreational purpose, no study has documented its effect on sperm quality. Elucidating the effect of codeine on sperm cells and the associated mechanisms may provide an insight into preventing drug-induced sperm damage. Twenty-one New Zealand white rabbits were randomized into three groups; control and codeine-treated. The codeine-treated groups received either 4 or 10mg/kg b.w of codeine for six weeks.Results: Codeine treatment led to significant decrease in sperm count, motility, viability, normal morphology, and sperm membrane integrity. This was associated with significant rise in sperm DNA fragmentation, oxidative damage, and caspase 3 activity. The percentage of sperm DNA fragmentation correlates positively with 8-hydroxy-2'-deoxyguanosine, a biomarker of oxidative DNA damage, and caspase 3 activity, a biomarker of apoptosis. The observed correlation was stronger between sperm DNA fragmentation and oxidative DNA damage than sperm DNA fragmentation and caspase 3 activity.Conclusion: This study revealed that chronic codeine exposure causes sperm DNA fragmentation and poor sperm quality primarily via oxidative stress rather than activation of caspase 3-dependent apoptosis. Findings of the present study may explain drug-induced male factor infertility, particularly, those associated with opioid use.

Reactive Oxygen Species Secreted by Leukocytes in Semen Induce Self-Expression of Interleukin-6 and Affect Sperm Quality

Reproductive tract inflammation is considered an important cause of male infertility. Increased leukocytes in semen can produce many reactive oxygen species (ROS), which affect sperm function. The aim of this study is to identify the main source of ROS in seminal plasma and to assess the effect of ROS on leukocytes. Semen samples (n = 20) with leukocyte concentration >1 × 10⁶ were collected from a male infertility clinic. This study mainly compares the sperm function parameters of the normal group and the semen white blood cell group >1 × 10⁶. The results identified that ROS in semen was closely related to sperm function parameters, and CD45⁺ leucocytes were the main source of ROS. Compared with the control group, the concentration of IL-2, IL-4, IL-6, IFN-γ, and TNF-α was higher in the experimental group. Leukocytes in semen may regulate the secretion of ROS through the mammalian target of rapamycin (mTOR) pathway. A considerable amount of ROS can upregulate the expression of IL-6 in leukocytes via the nuclear factor kappa-B (NF-kB) pathway.

How and Why to Define Unexplained Infertility?

Unexplained infertility represents up to 30% of all cases of infertility. It is a diagnosis of exclusion, where no cause for infertility may be identified in the investigation of the couple, be it anovulation, fallopian tube blockage, or severe male factor. Unexplained infertility therefore cannot be considered a diagnosis to which a specific treatment is directed, rather that it indicates a failure to reach a diagnosis of the true cause of infertility. In this review, we explore the evidence base and potential limitations of the current routine infertility assessment. We also aim to highlight the importance of considering the prognosis of each individual couple through the process of assessment and propose a reconsidered approach to treatment, targeted to the prognosis rather than the diagnosis. Ultimately, a better understanding of the mechanisms of infertility will reduce the number of couples diagnosed with "unexplained" infertility.

Diagnostic value of advanced semen analysis in evaluation of male infertility

Conventional semen analysis is the standard of care to initially evaluate the fertility status of a male patient. However, it has some limitations and among these are failure to correctly identify the aetiology underlying fertility problems, intra- and inter-observer variability and incomplete information about sperm function. Considering these drawbacks, advanced semen tests have been developed to assess male infertility, including sperm function tests, oxidative stress (OS) and sperm DNA fragmentation (SDF) tests. This review illustrates the commonly utilised sperm function techniques, along with the assays used to assess SDF and OS and their diagnostic value.

The possibility of integrating motile sperm organelle morphology examination (MSOME) with intracytoplasmic morphologically-selected sperm injection (IMSI) when treating couples with unexplained infertility

Purpose

To examine the efficacy of motile sperm organelle morphology examination (MSOME) and intracytoplasmic morphologically-selected sperm injection (IMSI) for unexplained infertility.

Methods

This historical study, included 271 couples with primary, unexplained infertility/male subfertility, treated at an outpatient, IVF clinic, 2015–2018. These couples underwent MSOME after ≥3 failed intrauterine insemination (IUI) cycles and ≥1 failed IVF-ICSI cycle. They proceeded to intracytoplasmic morphologically-selected sperm injection (IMSI) within 6 months of MSOME. IMSI is conducted on the day of oocyte pick-up with a fresh semen sample. Pregnancy and delivery rates were analyzed.

Results

The cohort was divided based on percentage of normal cells at MSOME: Group A included 55 with no normal cells, Group B, 184 with 0.5%≤ normal cells ≤1.5% and Group C, 32 with ≥2% normal cells. Normal spermatozoa were found in 49 (89%) of Group A after extensive search. Group A had higher pregnancy rate (62.7%) compared to B (47.2%, P = 0.05) and C (28.1%, P = 0.002). Group B had higher pregnancy rate than C (p = 0.045). Delivery rate was higher in Group A (52.1%) compared to B (34.1%, p = 0.023) and C (21.9%, p = 0.007). Pregnancy and delivery rates were higher in A compared to B+C (p = 0.018, p = 0.01, respectively).

Conclusions

MSOME may be useful for evaluating unexplained infertility. IMSI can be recommended for men with <2% normal spermatozoa at MSOME.

Sperm Proteome Analysis and Identification of Fertility-Associated Biomarkers in Unexplained Male Infertility

Up to 30% of men with normal semen parameters suffer from infertility and the reason for this is unknown. Altered expression of sperm proteins may be a major cause of infertility in these men. Proteomic profiling was performed on pooled semen samples from eight normozoospermic fertile men and nine normozoospermic infertile men using LC-MS/MS. Furthermore, key differentially expressed proteins (DEPs) related to the fertilization process were selected for validation using Western blotting. A total of 1139 and 1095 proteins were identified in normozoospermic fertile and infertile men, respectively. Of these, 162 proteins were identified as DEPs. The canonical pathway related to free radical scavenging was enriched with upregulated DEPs in normozoospermic infertile men. The proteins associated with reproductive system development and function, and the ubiquitination pathway were underexpressed in normozoospermic infertile men. Western blot analysis revealed the overexpression of annexin A2 (ANXA2) (2.03 fold change; P = 0.0243), and underexpression of sperm surface protein Sp17 (SPA17) (0.37 fold change; P = 0.0205) and serine protease inhibitor (SERPINA5) (0.32 fold change; P = 0.0073) in men with unexplained male infertility (UMI). The global proteomic profile of normozoospermic infertile men is different from that of normozoospermic fertile men. Our data suggests that SPA17, ANXA2, and SERPINA5 may potentially serve as non-invasive protein biomarkers associated with the fertilization process of the spermatozoa in UMI.

The management of unexplained infertility: an evidence-based guideline from the Canadian Fertility and Andrology Society

Unexplained infertility is a common diagnosis affecting as many as 50% of couples seeking infertility care. As a diagnosis of exclusion, its treatment remains largely empirical. Historically, a step-wise progression in treatment has been initiated with the least invasive, least expensive option followed by a gradual progression to therapies using assisted reproductive technology. In recent years there have been advocates for more rapid-progression IVF. This guideline from the Canadian Fertility and Andrology Society (CFAS) provides comprehensive, evidence-based recommendations for the treatment of unexplained infertility, including expectant management, laparoscopy, intrauterine insemination (IUI) alone, ovarian stimulation with oral agents or gonadotropins alone, ovarian stimulation + IUI, and IVF. The quality of supporting evidence for each recommendation is evaluated using the framework outlined by the Canadian Task Force on Preventive Health Care. This guideline recognizes that the therapeutic approach should be individualized taking into account patient age and duration of infertility, and emphasizes those strategies that are most likely to result in a healthy live birth.

Alterations in the sperm histone-retained epigenome are associated with unexplained male factor infertility and poor blastocyst development in donor oocyte IVF cycles

STUDY QUESTION

Is there a distinct sperm histone-retained epigenetic signature in unexplained male factor infertility patients resulting in compromised blastocyst development?

SUMMARY ANSWER

Using only donor oocyte IVF cycles, sperm DNA methylation patterns and miRNA profiles were significantly altered in normozoospermic patients resulting in poor blastocyst development, reflecting a subset of unexplained male factor infertility.

WHAT IS KNOWN ALREADY

Aberrant sperm DNA methylation has been associated with known male factor infertility, particularly noted in oligozoospermic patients. Unexplained male factor infertility remains a significant proportion of in vitro fertilization failures having unknown underlying physiology.

STUDY DESIGN, SIZE, DURATION

Sperm samples (n = 40) and blastocysts (n = 48) were obtained during fertile donor oocyte IVF cycles with normozoospermic parameters, thereby excluding known female and male infertility factors. Samples were divided into two groups based on blastocyst development (Good Group = ≥20% embryos with D5 grade 'AA' blastocysts, and ≥60% embryos of transferable quality on D5 and D6; Poor Group = ≤10% embryos with D5 grade 'AA' blastocysts, and ≤40% embryos of transferable quality on D5 and D6).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Samples were obtained from patients undergoing IVF treatments with informed consent and institutional review board approval. The Infinium HumanMethylation450 BeadChip microarray was used to identify histone-retained CpG island genes and genomic regions showing differences in sperm DNA methylation between the Good Group and the Poor Group. Pathway and gene network analysis for the significantly altered genes was performed, and targeted DNA methylation validation was completed for 23 genes and two imprinting control regions. Sperm miRNA profiles were assessed using the TaqMan® Human MicroRNA Array Card, with corresponding blastocyst mRNA gene expression examined by qRT-PCR.

MAIN RESULTS AND THE ROLE OF CHANCE

Our study is the first to investigate unexplained male factor infertility while significantly eliminating confounding female factors from our sample population by using only young fertile donor oocytes. We identified 1634 CpG sites located at retained histone CpG island regions that had significant sperm DNA methylation differentials between the two embryogenesis groups (P < 0.05). A largely hypermethylated profile was evident in the Good Group, with a small but distinct and statistically significant shift (P < 0.05) observed in the Poor Group. Genes involved in embryonic development were highly represented among histone-retained CpG sites with decreased methylation in the Poor Group (P < 0.05). Ten significantly altered sperm miRNAs (P < 0.05), correlated with altered target gene mRNA expression in the blastocysts from the Poor Group (P < 0.05). Taken together, significantly impacted sperm miRNA and target transcript levels in blastocysts from the Poor Group may contribute alongside aberrant sperm DNA methylation to the compromised blastocyst development observed.

LIMITATIONS, REASONS FOR CAUTION

Our examination of CpG island regions restricted to retained histones represents only a small part of the sperm epigenome. The results observed are descriptive and further studies are needed to elucidate the functional effects of differential sperm DNA methylation on unexplained male factor infertility and blastocyst development.

WIDER IMPLICATIONS OF THE FINDINGS

Slight epigenetic changes in sperm may have a cumulative effect on fertility and embryonic developmental competence. Knowledge of sperm epigenetics and inheritance has important implications for future generations, while providing evidence for potential causes of unexplained male factor infertility.

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was used for this study. None of the authors have any competing interest.

Antimüllerian hormone levels and antral follicle counts are not reduced compared with community controls in patients with rigorously defined unexplained infertility

OBJECTIVE

To test the hypothesis that women with unexplained infertility demonstrate evidence of diminished ovarian reserve when compared with a population of community controls.

DESIGN

Cross-sectional study.

SETTING

Multicenter university-based clinical practices.

PATIENT(S)

Study participants included 277 healthy, normo-ovulatory female partners with rigorously defined unexplained infertility randomly selected from a multicenter trial (Assessment of Multiple Intrauterine Gestations from Ovarian Stimulation). Controls included 226 healthy, normo-ovulatory women not seeking treatment for fertility from a community-based cohort (Ovarian Aging study).

INTERVENTION(S)

Serum antimüllerian hormone (AMH) assay at a central laboratory, FSH, fasting serum metabolic testing, transvaginal ultrasonography for antral follicle counts (AFCs), anthropometric measurements.

MAIN OUTCOME MEASURE(S)

Average AMH, AFC, and AMH/AFC were compared between infertile and control women by age. Analyses of covariance compared these outcomes while controlling for confounders, including age, race, body mass index, smoking history, and study site.

RESULT(S)

In our models, AMH, AFC, and AMH/AFC ovarian reserve indices did not differ between infertile women and community-based controls, after controlling for age, race, body mass index, smoking history, and study site.

CONCLUSION(S)

Currently utilized predictors of ovarian reserve do not discriminate women with rigorously defined unexplained infertility from healthy community-based women of similar demographic characteristics. Contrary to our hypothesis, among women with FSH in the normal range (≤12 IU/L), women with unexplained infertility did not show evidence of decreased ovarian reserve as measured by AMH and AFC. Ovarian reserve markers in isolation may not serve as predictors of future fertility.

Oxidation-reduction potential of semen: what is its role in the treatment of male infertility?

The diagnosis of male infertility relies largely on conventional semen analysis, and its interpretation has a profound influence on subsequent management of patients. Despite poor correlation between conventional semen parameters and male fertility potential, inclusion of advanced semen quality tests to routine male infertility workup algorithms has not been widely accepted. Oxidative stress is one of the major mediators in various etiologies of male infertility; it has deleterious effects on spermatozoa, including DNA damage. Alleviation of oxidative stress constitutes a potential treatment strategy for male infertility. Measurement of seminal oxidative stress is of crucial role in the identification and monitoring of patients who may benefit from treatments. Various tests including reactive oxygen species (ROS) assay, total antioxidant capacity (TAC) assay or malondialdehyde (MDA) assay used by different laboratories have their own drawbacks. Oxidation-reduction potential (ORP) is a measure of overall balance between oxidants and antioxidants, providing a comprehensive measure of oxidative stress. The MiOXSYS™ System is a novel technology based on a galvanostatic measure of electrons; it presents static ORP (sORP) measures with static referring to the passive or current state of activity between oxidants and antioxidants. Preliminary studies have correlated sORP to poor semen qualities. It is potentially useful in prognostication of assisted reproductive techniques outcomes, screening of antioxidants either in vivo or during IVF cycles, identification of infertile men who may benefit from treatment of oxidative stress, and monitoring of treatment success. The simplified laboratory test requiring a small amount of semen would facilitate clinical application and research in the field. In this paper, we discuss the measurement of ORP by the MiOXSYS System as a real-time assessment of seminal oxidative stress, and argue that it is a potential valuable clinical test that should be incorporated into the male infertility workup and become an important guide to the treatment of oxidative stress-induced male infertility.

A systematic review of recent clinical practice guidelines and best practice statements for the evaluation of the infertile male

PURPOSE

We systematically identified and reviewed the methods and consistency of recommendations of recently developed clinical practice guidelines (CPG) and best practice statements (BPS) on the evaluation of the infertile male.

METHODS

MEDLINE and related engines as well as guidelines' Web sites were searched for CPG and BPS written in English on the general evaluation of male infertility published between January 2008 and April 2015.

RESULTS

Four guidelines were identified, all of which reported to have been recently updated. Systematic review was not consistently used in the BPS despite being reported in the CPG. Only one of them reported having a patient representative in its development team. The CPG issued by the European Association of Urology (EAU) graded some recommendations and related that to levels (but not quality) of evidence. Overall, the BPS issued respectively by the American Urological Association and American Society for Reproductive Medicine concurred with each other, but both differed from the EAU guidelines with regard to methods of collection, extraction and interpretation of data. None of the guidelines incorporated health economics. Important specific limitations of conventional semen analysis results were ignored by all guidelines. Besides variation in the methodological quality, implementation strategies were not reported in two out of four guidelines.

CONCLUSIONS

While the various panels of experts who contributed to the development of the CPG and BPS reviewed should be commended on their tremendous efforts aiming to establish a clinical standard in both the evaluation and management of male infertility, we recognized inconsistencies in the methodology of their synthesis and in the contents of their final recommendations. These discrepancies pose a barrier in the general implementation of these guidelines and may limit their utility in standardizing clinical practice or improving health-related outcomes. Continuous efforts are needed to generate high-quality evidence to allow further development of these important guidelines for the evaluation and management of males suffering from infertility.

Engaging practicing gynecologists in the management of infertile men

In the modern era, contemporary management of male infertility has undergone groundbreaking changes with the introduction of new concepts, advanced testing, and therapeutic interventions. As practicing gynecologists are often the first physicians who encounter an infertile couple, it is essential that these clinicians are continuously updated about the new pearls and pitfalls of male infertility management. Semen analysis is commonly ordered by gynecologists. In 2010, the WHO released new cutoff reference values for the semen parameters adopting novel methodology, which has incited much debate. Reference values have been lowered in comparison with previous standards, with a direct clinical implication in decision-making strategies. Specialized sperm-function tests, such as sperm oxidative stress and sperm chromatin integrity assessments, became clinically available, thus offering an opportunity to better understand sperm dysfunctions concealed during routine semen analysis. Furthermore, the initial counseling of azoospermic men by an andrologically well educated gynecologist may alleviate the misconception and distress surrounding the false belief of sterility, and will clarify the available options of percutaneous and microsurgical sperm-retrieval techniques and assisted conception outcome. Regarding varicocele, which is commonly seen in infertile males, it is now clear that the best treatment option for infertile men with clinical varicocele is the microsurgical vein ligation. Natural conception is significantly improved after varicocelectomy, and recent data suggest that such treatment optimizes reproductive outcome of couples undergoing ICSI or micro-TESE sperm retrieval. Lastly, new therapeutic interventions, including oral antioxidant therapy and lifestyle modifications, have gained increasing attention, as they aid in alleviating male infertility.

Reactive Oxygen Species (ROS) in human semen: determination of a reference range

PURPOSE

High levels of reactive oxygen species (ROS) are a leading cause of male factor infertility. Measurement of ROS has been hampered by a lack of standardisation and confounding variables including choice of controls and sample selection. This study aimed to determine a reference range for ROS in human semen.

METHODS

Semen samples were obtained from men attending for routine semen analysis who gave informed consent for the study. Samples were assigned groups: Group 1 (N = 94) normal semen parameters, no leucocytospermia; Group 2 (N = 100) abnormal semen parameters, no leucocytospermia; Group 3 (N = 41) any semen parameters with leucocytospermia. ROS levels were assayed in fresh neat semen using a chemiluminescence assay measured in a single tube luminometer. Data are reported in relative light units (RLU)/sec/10(6) sperm

RESULTS

ROS levels were significantly different between Groups 1, 2 and 3 (19.75 ± 8.12, 95.03 ± 33.63, 890.17 ± 310.23 RLU/sec/10(6) sperm respectively; p < 0.001). Group 3 gave the highest value confirming this group as the optimum choice for positive controls. The reference range < 24.1 RLU/sec/10(6) sperm was determined by ROC analysis that differentiates a reference population (Group 1) from a positive control group (Group 3), optimising the sensitivity and specificity (80.5 and 87.2% respectively) of the test.

CONCLUSIONS

We have determined a reference range for ROS in human semen and identified a patient population that falls outside the normal range. This simple, cost effective assay can be incorporated into routine diagnostic testing to aid in the diagnosis of male infertility, especially with regard to unexplained infertility.

Integrated miRNA and mRNA expression profiling to identify mRNA targets of dysregulated miRNAs in non-obstructive azoospermia

The aim of this study was to identify mRNA targets of dysregulated miRNAs through the integrated analysis of miRNA and mRNA expression profiling in men with normal versus impaired spermatogenesis. The expression of mRNAs and miRNAs in testicular tissues obtained from males with non-obstructive azoospermia (NOA, n = 4) or obstructive azoospermia (OA, n = 3) with normal spermatogenesis was analyzed using microarray technology. Some of the most interesting results were validated by real time PCR using samples from the same cohort. Ninety-three miRNAs and 4172 mRNAs were differentially expressed in the NOA and normozoospermic OA patients. In addition to confirming that significantly dysregulated genes and miRNAs play pivotal roles in NOA, promising correlation signatures of these miRNA/mRNA pairs were discovered in this study. The functional classification of the miRNA/mRNA pairs revealed that differentially expressed genes were most frequently associated with spermatogenesis, the cell meiosis, the cell cycle, and the development of secondary male sexual characteristics. This is the first systematic profiling of both mRNA and miRNA in testicular tissues of patients with NOA and OA. Our results indicate that the phenotypic status of NOA is characterized by the dysfunction of normal spermatogenesis when compared with OA or normozoospermic males.

A translational medicine appraisal of specialized andrology testing in unexplained male infertility

The diagnostic and prognostic validity of sperm function biomarkers is particularly relevant for males with unexplained infertility in which routine semen analysis fails to detect subcellular sperm dysfunctions. In this general review, we examine the role and significance of specialized andrology laboratory tests from past to present and provide a glance toward the future. We concluded that the assessment of sperm DNA damage and oxidative stress provide a relatively independent measure of fertility that yields diagnostic and prognostic information complementary to, but distinct and more significant than, standard sperm parameters. Since none of the available methods for such testing have been fully translated, further research is necessary to evaluate their cost-effectiveness when applied in large scale to daily medical practice. Application of translational medicine concepts would also be useful to accelerate the clinical application of recent discoveries in the fields of genomics, proteomics and metabolomics.

Unexplained male infertility: diagnosis and management

Unexplained male infertility is a diagnosis reserved for men in whom routine semen analyses results are within normal values and physical as well as endocrine abnormalities were ruled out. In addition to erectile problems and coital factors, immunologic causes and sperm dysfunction may contribute to such condition. New etiologies of unexplained male infertility include low level leukocytospermia and mitochondrial DNA polymerase gene polymorphism. Contemporary andrology may reveal cellular and sub-cellular sperm dysfunctions which may explain subfertility in such cases, thus aiding the clinician to direct the further work-up, diagnosis and counseling of the infertile male. The objective of this article is to highlight the concept of unexplained male infertility and focuses on the diagnosis and treatment of this condition in the era of modern andrology and assisted reproductive techniques. Extensive literature review was performed using the search engines: Pubmed, Science-direct, Ovid and Scopus.

Organizational and functional status of the Y-linked genes and loci in the infertile patients having normal spermiogram

Male fertility is an orchestrated interplay of loci on the Y chromosome with a number of genes from across the other chromosomes. In this context, micro-deletions in the Y chromosome have been correlated with spermatogenic failure often leading to infertility. However, causes of infertility in the patients with the normal spermiogram have remained unclear and therefore pose another level of challenge. In the present study, we analyzed 64 STSs, studied different Y-linked genes and loci and conducted single nucleotide variant (SNV) analyses in 31 infertile males with normal spermiogram along with 67 normal fertile males (NFMs) to gain an insight into the organization of their Y chromosome. Further, employing quantitative real-time PCR (qPCR), we studied copy number variation of DYZ1 arrays and three genes and mutational status of SRY by direct sequence analyses. STS analyses of the AZFa, b and c regions in these patients showed known and new mutations. Further, copies of DAZ and BPY2 in the patients were found to be affected compared to those in NFMs. All the patients had normal copy number of the SRY however its sequence analysis (in silico) showed mutations in eight patients. In four of these eight patients, SRY mutations resulted into truncated proteins. Similarly, DYZ1 analysis showed micro-deletions and it's much reduced copy number as compared to those in NFMs. Present study in males with unexplained infertility revealed deletions similar to those observed in oligospermic and azoospermic patients. Thus, there are some common but still unknown factors underlying infertility in these patients irrespective of their spermatogenic status. This work is envisaged to augment DNA diagnosis, proving beneficial in the context of in vitro fertilization (IVF) and genetic counselling.

What every gynecologist should know about male infertility: an update

PURPOSE

Our article reviews the evolving concepts in the field of male infertility for gynecologists and other health professionals involved in the care of men and women experiencing difficulty in having a child. The increased knowledge will help in the better management and treatment of infertile couples.

METHODS

Review of literature through Pubmed, Science Direct, Online Library.

RESULTS

Gynecologists are often the first healthcare providers to assess an infertile couple. Because half of all infertility problems stem from male factors, it is crucial for the gynecologist to remain updated on the main conditions that cause male infertility as well as current diagnostic tools and treatment options, including conventional strategies and assisted reproductive techniques.

CONCLUSIONS

Extraordinary advances have been achieved in the field of male infertility over the past several years and many old concepts are now challenged. Therefore, it is imperative that male infertility physicians should update the gynecologists about the recent advances in the work-up of infertile men in terms of diagnosis and management. Such convention will help improve the standards of care for the infertile couple and enhance the cooperation between male and female reproductive endocrinologists.

Recurrent pre-clinical pregnancy loss is unlikely to be a 'cause' of unexplained infertility

BACKGROUND

A proportion of women with 'unexplained' infertility may present with subfertility because their pregnancies fail before they are clinically recognized. In order to test whether pre-clinical early pregnancy losses (EPL) occur more frequently in women with unexplained infertility, serial urinary hCG concentrations were measured to compare EPL per cycle rates following spontaneous conception in patients with unexplained infertility versus healthy volunteers.

METHODS

Sixty patients under 39 years of age with unexplained infertility and 60 healthy controls, who were trying to conceive spontaneously, participated in this study. All participants were asked to collect daily urine samples from cycle day 14 until menstruation for three consecutive cycles or until a positive pregnancy test was obtained. Urinary hCG and creatinine levels were measured by immunoassay. Implantation was detected when urinary hCG levels rose above reference levels constructed from samples obtained from 12 women not attempting to conceive. EPL rates were determined by a linear mixed model using logarithmically transformed hCG/creatinine data.

RESULTS

In the 133 cycles of 60 women with unexplained infertility, just one implantation was detected, which became an ongoing pregnancy. In contrast, in 103 such cycles in 46 control patients, 30 implantations were detected (24 clinical pregnancies, 6 cases of EPL). The odds ratio for EPL/cycle in the unexplained versus control group was 0 (95% confidence interval: 0-0.795, P = 0.026).

CONCLUSIONS

Our data do not support the hypothesis that recurrent EPL may present as unexplained infertility. Post-implantation failure is therefore unlikely to contribute significantly to the presentation of subfertility.

Cholesterol-to-phospholipid ratio in whole sperm and seminal plasma from fertile stallions and stallions with unexplained subfertility

Semen samples were collected from six fertile stallions and seven stallions with unexplained infertility. Percentages of motile sperm (77.5 +/- 11.3 versus 67.5 +/- 12.2, P = 0.2), and progressively motile sperm (70.8 +/- 13.6 versus 60.7 +/- 14.0, P = 0.2) were similar between fertile and subfertile stallions, respectively. Morphologic characteristics in ejaculates of control and affected stallions (% normal: 60.2 +/- 18.2 versus 52.9 +/- 11.3, P = 0.4; % abnormal heads 7.3 +/- 4.8 versus 12.1 +/- 5.0, P = 0.11; and % abnormal acrosomes 1.6 +/- 2.1 versus 3.0 +/- 3.4, P = 0.4) did not differ. After incubation with the calcium ionophore A23187, acrosome reaction rate of sperm from fertile stallions was 96 +/- 2.8% whereas only 2.9 +/- 2.5% of sperm from stallions with unexplained subfertility had acrosome reacted (P < 0.001). Molar amounts of cholesterol and phospholipid in whole sperm and seminal plasma did not differ (P > 0.1) between fertile and subfertile stallions. However, the molar ratio of cholesterol-to-phospholipid was 2.5 times greater in the seminal plasma (P = 0.09) and 1.9 times greater (P = 0.009) in whole sperm of subfertile stallions compared to fertile stallions.

Image content influences men's semen quality

There is increasing evidence from non-human animals that males adjust their ejaculate expenditure according to the risk of sperm competition. In this study we show that, after controlling for lifestyle factors known to influence semen quality, human males viewing images depicting sperm competition had a higher percentage of motile sperm in their ejaculates. Many lifestyle variables were confirmed to influence semen quality, including the recent suggestion that storage of mobile phones close to the testes can decrease semen quality.

Negative effects of increased sperm DNA damage in relation to seminal oxidative stress in men with idiopathic and male factor infertility

OBJECTIVE

To examine the effects of increased sperm DNA damage in relation to seminal oxidative stress in men with idiopathic and male factor infertility. Prospective study.

SETTINGS

Infertility clinic at a tertiary care academic institution.

PATIENT(S)

Ninety-two infertile men with normal female partners. Sixteen fertile donors served as the control group.

INTERVENTION(S)

Standard semen analysis and assessment of levels of seminal oxidative stress. Assisted reproductive techniques in 33 of the 92 patients (IUI [n = 19], IVF [n = 10], and intracytoplasmic sperm injection [n = 4]).

MAIN OUTCOME MEASURE(S)

Sperm DNA damage by sperm chromatin structure assay. Results were expressed as DNA fragmentation index.

RESULT(S)

Patients were classified as having either idiopathic (n = 23) or male factor infertility (n = 69). Patients with idiopathic and male factor infertility had significantly higher DNA fragmentation index and oxidative stress compared with the case of fertile donors. A clinical pregnancy was achieved in 9 (27%) of 33 patients with assisted reproductive techniques. Significantly higher DNA fragmentation index and oxidative stress were found in men who failed to initiate a pregnancy after assisted reproductive techniques (n = 24), compared with the cases of those who succeeded and of the fertile donors. DNA fragmentation index was correlated positively with oxidative stress (r = 0.27), and negatively with fertilization (r = -0.70) and embryo quality (r = -0.70).

CONCLUSION(S)

Sperm DNA damage is significantly increased in men with idiopathic and male factor infertility and in men who failed to initiate a pregnancy after assisted reproductive techniques. Such an increase may be related to high levels of seminal oxidative stress.

Intensive hormone monitoring in women with unexplained infertility: evidence for subtle abnormalities suggestive of diminished ovarian reserve

OBJECTIVE

To determine hormone levels across the menstrual cycle in women with rigorously defined unexplained infertility.

DESIGN

Prospective study.

SETTING

National Center for Infertility Research at Michigan.

PATIENT(S)

Evaluation of 1,885 women with infertility identified 12 women who met the following rigorously defined criteria for unexplained infertility: [1] infertility of > or = 24 months' duration, with no male factor, anatomic or functional disorders of the reproductive tract, or immunologic infertility; [2] normal body mass index (BMI); (3) ovulatory cycles ranging from 26 to 32 days; [4] normal luteal phase determined by endometrial biopsy; and [5] normal baseline hormonal profile. Controls (n = 12) were healthy, parous women with normal ovulatory cycles and normal hormonal screens, and were matched for age and BMI with patients.

MAIN OUTCOME MEASURE(S)

Daily gonadotropin and steroid hormone levels across the menstrual cycle.

RESULT(S)

Basal FSH and LH levels in the early, middle and late follicular phases were increased significantly in the group with unexplained fertility compared with the normal controls. The mean (+/-SD) early follicular FSH levels were 7.0 +/- 0.57 mIU/mL in the unexplained-infertility group and 4.7 +/- 0.37 mIU/mL (conversion factor to SI units, 1.00) in the normal controls, respectively. There was no difference between groups over the periovulatory or luteal phase. Midluteal mean (+/-SD) P levels were lower in the unexplained-infertility group than in the normal controls (13.7 +/- 1.6 versus 24.0 +/- 3.2 ng/mL [conversion factor to SI units, 3.180]). Mean E2 concentrations were elevated in the group with unexplained infertility versus normal controls in the early through the late follicular phase but reached significance only in the midfollicular phase. Mean prolactin levels were elevated consistently across the menstrual cycle in the unexplained-infertility group compared with those in normal controls but reached significance only in the early and late follicular and midluteal phases of the cycle. Cortisol concentrations were similar between the two groups.

CONCLUSION(S)

These data indicate that there are subtle alterations in various hormones measured across the menstrual cycle in women with unexplained infertility compared with those in normal controls, suggesting a diminished ovarian reserve.

Assessment of hyperactivation, acrosome reaction and motility characteristics of spermatozoa from semen of men of proven fertility and unexplained infertility

Semen from men of proven fertility was compared with that of men with unexplained infertility to determine differences in spermatozoal functions such as hyperactivation and acrosome reaction and spermatozoal motility characteristics. The hyperactivated spermatozoa in both groups could be visualised on the monitor of the Computer Assisted Semen Analyser and they exhibited 'circling', 'thrashing', 'starspin' and 'helical' motility patterns and the mean hyperactivation rates were not significantly different. However, 20% of the men with unexplained infertility did not exhibit hyperactivation compared to only 4% in the fertile group. Furthermore, the semen from infertile men when evaluated for hyperactivation could be categorised into two groups with those having lower hyperactivation (< 10% or < 6% after 4 and 6 h of incubation respectively), forming the first group, and those having a higher hyperactivation rate constituting the second group. In the fertile men such distinct groups were not visible and the percentage hyperactivation ranged from 1 to 16%. No significant differences were observed in the rate of acrosome reaction of fertile and unexplained infertile men. The non-hyperactivated spermatozoa from unexplained infertile men showed a significant increase in path velocity (VAP), curvilinear velocity (VCL) and amplitude of lateral head displacement (ALH) and a decrease in linearity (LIN) and straightness (STR) compared to spermatozoa from fertile men. Furthermore, the hyperactivated spermatozoa from infertile men also showed an increase in progressive velocity (VSL) (only after 2 h of incubation) and LIN and decrease in ALH and beat cross frequency (BCF) compared to spermatozoa from fertile men. The results are discussed in the light of the importance of the above spermatozoal functions and spermatozoal parameters in fertilization.

Unexplained infertility: evaluation of the luteal phase; results of the National Center for Infertility Research at Michigan

OBJECTIVE

To evaluate the luteal phase in women with rigorously defined unexplained infertility.

DESIGN

Prospective study.

SETTING

National Center for Infertility Research at Michigan.

PATIENT(S)

Evaluation of 1,885 women with infertility identified 12 women who met the rigorously defined criteria for unexplained infertility: [1] infertility of > or = 24 months duration, with no male factor, anatomic-functional disorders of the reproductive tract, or immunologic infertility; [2] normal body mass index (BMI); [3] ovulatory cycles ranging from 26 to 32 days; [4] normal luteal phase determined by endometrial biopsy; and [5] normal baseline hormonal profile. Controls (n = 12) were healthy, parous women with normal ovulatory cycles, normal hormonal screen, and were matched for age and BMI to patients.

MAIN OUTCOME MEASURE(S)

Pattern of follicular growth rate and luteal phase hormonal profile.

RESULT(S)

Women with unexplained infertility did not differ in menstrual cycle characteristics, follicular growth rate or mean preovulatory follicle diameter, or endometrial biopsy dating. The mean levels of P tended to be lower in the unexplained infertility group throughout the luteal phase, but only the midluteal interval reached statistical significance. Luteal phase mean integrated P or urinary PDG levels of unexplained infertility women did not differ from those of fertile controls. The ratio of integrated E2:P also was significantly greater in women with unexplained infertility than in fertile controls.

CONCLUSION(S)

Women with rigorously defined unexplained infertility have subtle hormonal anomalies during the luteal phase when compared with fertile controls.

Contribution of the male factor to unexplained infertility: a review

The more exhaustive the evaluation of couples with unexplained infertility, the more likely is the opportunity for detecting the aetiological factor responsible for infertility. Transport of spermatozoa through the upper genital tract and their ability to fertilize the oocyte are two obscure areas for the conventional evaluation of infertility. Although research in the former area is limited, there is indirect evidence that impaired sperm transport could be one of the causes of infertility in some couples with otherwise unexplained infertility. on the other hand, the availability of sperm function tests and the correlation of their results with in-vitro fertilization rates have allowed the detection of a previously hidden male factor in couples with unexplained infertility. It has been demonstrated that couples suffering unexplained infertility have significantly lower in-vitro fertilization rates in comparison with patients with tubal problems. These results can be explained because of several case control studies in patients with unexplained infertility have reported defects in capacitation and sperm motion characteristics, binding of the spermatozoa to the zone pellucida, acrosome reaction, acrosin activity of the spermatozoa, and the ability of the spermatozoa to penetrate zona-free hamster oocytes. These observations suggest that methods for assessing the fertilizing capacity of the spermatozoa have to incorporated in the evaluation of couples with unexplained infertility in order to amplify the scope of the workup and to better decide the appropriate treatment for these couples.

Controlled ovarian hyperstimulation with or without intrauterine insemination for the treatment of unexplained infertility

OBJECTIVE

To evaluate whether there are any benefits from intrauterine insemination (IUI) as opposed to timed intercourse (TI) in stimulated ovarian cycles in couples with longstanding, unexplained infertility.

METHODS

Forty-six couples with diagnoses of unexplained infertility were evaluated in a crossover study after a total of 141 cycles. Sixty-seven cycles were with IUI after controlled ovarian hyperstimulation (COH) while 74 cycles were after COH and TI.

RESULTS

The pregnancy rate after COH/TI was 16.7% and after COH/IUI 45.2%. Cycle fecundity however was 8.9% after COH/TI and 25.7% after COH/IUI, which is a statistically significant difference (P < 0.05).

CONCLUSIONS

A trial of human menopausal gonadotropin and IUI is justified in couples with prolonged infertility of unknown cause.

Gender differences and perceptions about childbearing among infertile couples

OBJECTIVE

To explore gender differences and responses of infertile couples to childbearing issues.

DESIGN

Data analysis from the first wave of a larger three-wave prospective panel study. Face-to-face interviews with both husbands and wives were conducted.

SETTING

Husbands and wives were interviewed separately in their homes. One was generally interviewed immediately after the other.

PARTICIPANTS

One hundred sixty-one infertile couples in southeastern Michigan were interviewed in 1988.

MEASURES

Variables of interest included the self-recognized source of the fertility problem, the importance of children to individuals, stress associated with infertility treatment, the number of tests and treatments received, the acceptability of indicated treatments, the length of time couples expected it would take to have a child, and the ideal and expected number of children.

RESULTS

Women experienced significantly more stress from tests and treatment, placed greater importance on having children, were more accepting of indicated treatments, and wanted more children than men did.

CONCLUSIONS

Implications for nurses working with infertile couples are discussed, including provision of emotional support, evaluation of perceptions of success, assessment of couples' expectations, and inclusion of husbands in decision making.

Does patient semen quality alter during an in vitro fertilization (IVF) program in a manner that is clinically significant when specific counseling is in operation?

PURPOSE

It has been shown that the stress of infertility may impair semen quality. Whether counseling can attenuate this affect is unproven. This study examines, in an IVF program setting, where specific counseling is in operation, whether semen collected on the day of oocyte recovery is significantly different from that obtained during the prior clinical suitability assessment of the couple.

RESULTS

In the 125 consecutive couples examined, there were no significant overall differences in semen volume or sperm density. There was a significant increase in sperm motility on the day of oocyte retrieval (P < 0.001). Twenty-three patients (18.4%) showed an increase in quality, and 21 (16.8%) a decrease, on the day of oocyte recovery. The environment of production appeared to exert no influence. Fertilization failure occurred in seven couples, three (14%) of whom presented for the first time with decreased semen parameters on the day of IVF. This compares with 1 of 23 (4%) fertilization failure in those whose parameters increased.

CONCLUSION

The semen quality of the vast majority of the patients studied in this highly counseled program does not appear to be significantly affected by the superstress of participation in the day of oocyte recovery.

Sperm head ultramorphology and chromatin stability of males with unexplained infertility who fail to fertilize normal human ova in vitro

An in vitro nuclear chromatin decondensation test, and quantitative nuclear ultramorphology analysis, were performed on 18 males judged to be infertile, by two failures in in vitro fertilization, and 16 fertile males. These two clinical groups only differed significantly in (1) the direction of their chromatin stability change, which took place 30-120 min post-ejaculation while stored in the seminal plasma, and (2) in the incidence of the hypoelongated sperm-head. Generally, the fertile male group exhibited positive chromatin stability change after prolonged storage, and low incidence of hypoelongated sperm heads, and vice versa in the unexplained infertile group. When the nuclear chromatin decondensation test and quantitative ultramorphology analysis were performed in step-wise fashion, it was possible to correctly classify 94% of the fertile cases with 6% of false-negative, and 89% of the unexplained infertile cases with 11% of false-positive. Therefore, it appears that these tests might be of benefit clinically for identifying functional properties of sperm-cells in unexplained infertile males, which cannot be detected by routine semen analysis.

Ethiodol oil contrast medium inhibits macrophage phagocytosis and adherence by altering membrane electronegativity and microviscosity

OBJECTIVE

To examine the effect of Ethiodol oil-soluble contrast medium and Sinografin aqueous-soluble contrast medium on macrophage function. After the observation that Ethiodol alters macrophage phagocytosis and adherence, we sought to determine the mechanism of action by which oil-soluble contrast medium alters the macrophage membrane.

DESIGN

The P388D1 cell line was used as a consistent source of macrophages for all experiments. The uptake of 3H-labeled candida albicans was determined in macrophages exposed to 1:100, 1:400, or 1:800 dilutions of Ethiodol, Sinografin (S.R. Squibb, Princeton, NJ) or untreated media. To evaluate the macrophage adherence, 51Cr-labeled macrophages were exposed to the same dilutions of the contrast media. Specific membrane properties, Fc receptor levels, electronegativity, and microviscosity were assessed by flow cytometry after exposure to 1:100 dilutions of Ethiodol or Sinografin.

RESULTS

Macrophage phagocytosis was decreased upon exposure to 1:100 and 1:400 dilutions of Ethiodol contrast medium, whereas adherence was reduced at the 1:100 dilution of Ethiodol. There was no effect of any dilution of Sinografin. There was a reduction in membrane electronegativity and microviscosity, but not Fc receptor levels, after exposure to a 1:100 dilution of Ethiodol.

CONCLUSIONS

This study establishes a decrease in macrophage phagocytosis and adherence after exposure to Ethiodol oil-soluble contrast medium. We established that this alteration in membrane function is caused by a reduction of membrane negative surface charge and microviscosity. This may suggest a mechanism of action for the therapeutic effect of oil-contrast hysterosalpingograms in women with unexplained infertility.

Is fertility-problem stress different? The dynamics of stress in fertile and infertile couples

OBJECTIVE

To compare the dynamics of fertility-problem stress experienced by wives and husbands in infertile couples with the dynamics of stress from other sources experienced by members of couples presumed to be fertile.

DESIGN

Relationships of stress to four marriage factors and four aspects of life quality (subjective well-being) are examined within a causal modeling framework using data from structured interviews.

SETTING

Face-to-face interviews were conducted in study participants' homes.

PARTICIPANTS

Wives and husbands from 157 couples with primary infertility and from 82 presumed-fertile couples were studied.

MAIN OUTCOME MEASURES

Final outcome measures were four multi-item scales assessing life quality with regard to the marriage, own self-efficacy, own health and appearance, and life as a whole. Intervening outcome scales measured four marriage factors: marital conflict, sexual self-esteem, sexual dissatisfaction, and frequency of intercourse.

RESULTS AND CONCLUSIONS

Higher levels of stress, regardless of whether that stress was from attempting to solve a fertility problem or another problem, were related to reduced marital functioning and decreased life quality. For husbands, the strengths of the linkages did not depend on the source of the stress. For wives, however, the causal model suggested that fertility-problem stress had stronger negative impacts on sense of sexual identity and self-efficacy than did stress from other problems (P less than 0.05). Stress from any source had more impact on the lives of wives than of husbands, more impact on satisfaction with self and general well-being than on satisfaction with the marriage or health, and affected life quality mostly indirectly through its impacts on the marriage factors.

Evaluation of immunological infertility

To evaluate the frequency with which immunological factors are associated with infertility, 92 couples with unexplained infertility were studied by using assays to detect anti-sperm antibodies (ASA), human leukocyte antigen tissue types (HLA), lymphocytotoxic antibodies (LCA), and inhibitors of mixed lymphocyte culture (MLC) and mouse blastocyst assay (MBA). Seventy-three of the women had blood assayed for antiphospholipid antibodies (APA). The frequencies of APA, ASA, LCA, inhibitors of MLC and MBA, as well as HLA associations previously reported to be related to infertility (B locus blanks, single DQ locus in offspring, greater than 1 DR sharing between mates) among 92 infertile couples were compared with those observed among 41 fertile control couples. No significant differences in the frequencies of APA, ASA, MBA, and HLA associations between fertile and infertile couples were observed. Fertile couples demonstrated the presence of wife anti-husband LCA and MLC inhibitors more frequently than did infertile couples (51% vs. 8%, P = 0.0001 and 29% vs. 4%, P = 0.002, respectively). While APA, ASA, HLA tissue typing, LCA, and MLC and MBA have been previously reported as being markers of autoimmune and alloimmune responses relating to reproductive outcome, the current data suggest that more specific markers are necessary to diagnose immunological components of infertility.

Prevalence of infertility: international data and problems of measurement

This paper discusses the various research options open for measuring the prevalence of infertility. National and regional surveys are both population-based studies but with different methodological approaches. National surveys give information on the various parameters of a couple's reproductive life and indicate the main trends concerning infertility. They give an approximate estimate of the prevalence of infertility, depending on the validity of the collected data. Regional studies can measure the prevalence, incidence, causes and distribution of primary and secondary infertility. When properly carried out, i.e., when the census of infertile couples can be considered as almost exhaustive and when the population studied is representative of the general population, their results can then be inferred on a national scale. Epidemiologists working in infertility have a duty to design appropriate methodologies, thus making public health policymakers aware of the aspects and implications of different types of infertility surveys.

Measurements of salivary progesterone throughout the menstrual cycle in women suffering from unexplained infertility reveal high frequency of luteal phase defects

Forty-five women suffering from unexplained infertility collected saliva for progesterone (P) measurements every morning during 1 to 3 complete cycles. A total of 27 cycles analyzed were unstimulated, 19 were stimulated by clomiphene citrate (CC), and 7 with CC, human menopausal gonadotropin (hMG), and human chorionic gonadotropin (hCG). Compared with reference profiles of salivary P from 27 normal cycles, the length and magnitude of P secretion were significantly lower in the infertility group. Luteal P concentrations were normalized during CC stimulation and significantly elevated during the CC-hMG-hCG stimulation. The other abnormalities found in the salivary P profiles of these patients included preovulatory P peaks, interruption of P secretion during luteal phase, and high P level at the beginning of menstruation. The results suggest that patients with prolonged unexplained infertility represent a heterogenous population with common luteal phase defects. The disturbance is effectively corrected with treatments stimulating gonadotropin secretion.