Sperm morphology: classification drift over time and clinical implications

Predictive Value of Teratospermia During Initial Sperm Analysis on the Success of Intrauterine Insemination Cycles

OBJECTIVE

To evaluate the predictive value of sperm morphology, specifically teratospermia, seen during initial semen analysis on the success of intrauterine insemination (IUI) cycles and pregnancy outcomes.

METHODS

A retrospective cohort analysis on patients undergoing IUI at a large US fertility network. Baseline demographic characteristics, primary infertility diagnoses, and pregnancy outcomes were recorded. A total of 27,925 IUI cycles in 16,169 unique patients were analyzed. IUI cycles were grouped by a sperm morphology of 1% (n = 3799), 2% (n = 5506), 3% (n = 4857), or 4% or greater (n = 13,763). The outcome measures were pregnancy rate (positive pregnancy test), clinical pregnancy rate (CPR) (ultrasound confirmation of a gestational sac with a yolk sac around 5-6 weeks), live birth rate, and miscarriage rate.

RESULTS

Sperm morphology is a significant predictor of pregnancy rate (P = <.001), CPR (P =.011), and live birth rate (P = .026) following IUI. In each of these outcome measures, patients with 1% normal forms had the lowest percentage of success, and patients with 4% or greater normal forms had the most success. Relative outcome percentages, however, were similar in each group. Live birth rates in the 1%, 2%, 3%, and >4% group were 12.3%, 13.1%, 12.7%, and 13.9%, respectively. Sperm morphology is not a significant predictor of miscarriage rate per clinical pregnancy post-IUI (P = .054).

CONCLUSION

Sperm morphology was a statistically significant predictor of pregnancy, clinical pregnancy, and live birth but not miscarriage rate after an IUI cycle. Higher morphology percentages were associated with increasingly favorable outcomes. However, the small observed differences did not demonstrate clinical significance.

L-Arginine abrogates maternal and pre-pubertal codeine exposure-induced impaired spermatogenesis and sperm quality by modulating the levels of mRNA encoding spermatogenic genes

Introduction

Although, codeine has been demonstrated to lower sperm quality; the effects of maternal and prepubertal codeine exposure on male offspring is yet to be reported. In addition, the effect of arginine on codeine-induced decline in sperm quality has not been explored. This study investigated the impact of maternal and prepubertal codeine exposure on spermatogenesis and sperm quality in F1 male Wistar rats to study the effect that codeine may have during recreational use in humans. Also, the effect of arginine supplementation on codeine-induced alteration in spermatogenesis and sperm quality was evaluated.

Methods

Female rats were treated with either 0.5 ml distilled water or codeine orally for eight weeks, and then mated with male rats (female:male, 2:1). The F1 male offsprings of both cohorts were weaned at 3 weeks old and administered distilled water, codeine, arginine, or codeine with arginine orally for eight weeks.

Results

Prepubertal codeine exposure in rats whose dams (female parents) were exposed to codeine delayed puberty and reduced the weight at puberty. Prepubertal codeine exposure exacerbated maternal codeine exposure-induced reduced total and daily spermatid production, sperm count, sperm motility, and normal sperm form, as well as impaired sperm plasma membrane integrity and increased not intact acrosome and damaged sperm DNA integrity. These perturbations were accompanied by a decrease in mRNA levels encoding spermatogenic genes, testicular testosterone and androgen receptor (AR) concentrations, and upregulation of sperm 8-hydroxydeoxyguanosine (8OHdG). Prepubertal arginine supplementation mitigated codeine-induced alterations.

Discussion

This study provides novel experimental evidence that maternal and prepubertal codeine exposure reprogramed spermatogenesis and sperm quality of male FI generation by decreasing mRNA levels encoding spermatogenic genes and AR via oxidative stress-mediated signaling, which was abrogated by prepubertal arginine supplementation.

Changes in Semen Analysis over Time: A Temporal Trend Analysis of 20 Years of Subfertile Non-Azoospermic Men

PURPOSE

To examine trends of population-level semen quality over a 20-year period.

MATERIALS AND METHODS

We performed a retrospective review of data from the andrology lab of a high volume tertiary hospital. All men with semen samples between 2000 and 2019 were included and men with azoospermia were excluded. Semen parameters were reported using the World Health Organization (WHO) 4th edition. The primary outcome of interest was changes in semen parameters over time. Generalized least squares (GLS) with restricted cubic splines were used to estimate average-monthly measurements, adjusting for age and abstinence period. Contrasts of the estimated averages based on GLS between the first and last months of collection were calculated.

RESULTS

A total of 8,990 semen samples from subfertile non-azoospermic men were included in our study. Semen volume decreased over time and estimate average at the beginning and end were statistically different (p<0.001). Similarly sperm morphology decreased over time, with a statistically significant difference between estimated averages from start to finish (p<0.001). Semen pH appeared to be increasing over time, but this difference was not significant over time (p=0.060). Sperm concentration and count displayed an increase around 2003 to 2005, but otherwise remained fairly constant over time (p=0.100 and p=0.054, respectively). Sperm motility appeared to decrease over time (p<0.001).

CONCLUSIONS

In a large sample of patients presenting to a single institution for fertility assessment, some aspects of semen quality declined across more than two decades. An understanding of the etiologies and driving forces of changing semen parameters over time is warranted.

Sperm morphology from the actual inseminated sample does not predict clinical pregnancy following intrauterine insemination

Objective

To determine the effect of sperm morphology from the specific sample used for intrauterine insemination (IUI) on clinical pregnancy rates (CPR).

Design

Prospective cohort study.

Setting

Academic fertility clinic.

Patients

Couples undergoing IUI July 2016-January 2017.

Interventions

Morphology slides were prepared from the semen sample produced for IUI.

Main Outcome Measures

CPR was measured by detection of cardiac activity. Multiple logistic regression modeling was performed to determine the association of sperm morphology with CPR, controlling for age, antimüllerian hormone level, and post-wash total motile sperm count.

Results

Semen analyses, including Kruger strict criteria for morphology from the actual sample inseminated, were reviewed for 155 couples, comprising 234 total treatment cycles. The percent normal morphology significantly differed between the preliminary semen analysis and the IUI sample (-2.0% +3.7% (95% CI -2.55, -1.53). Of the total 234 treatment cycles, 8.6% resulted in clinical pregnancy. When categorized by strict morphology >4%, <4%, and <1%, the CPR was 6.6%, 9.8%, and 10.9%, respectively. In couples with otherwise normal semen parameters (isolated teratospermia), CPR by >4%, <4%, and <1% normal forms was 7.2%, 9.8%, and 11.1%, respectively. There was no significant association between the percent normal morphology and CPR in multivariate analysis.

Conclusions

This study evaluating the morphology of the actual inseminated sample did not find differences in CPR following IUI among couples with normal and abnormal sperm morphology, including severe teratospermia. Abnormal sperm morphology should not exclude couples from attempting IUI.

Prepubertal acrylamide exposure causes dose-response decreases in spermatic production and functionality with modulation of genes involved in the spermatogenesis in rats

The increase in human infertility prevalence due to male reproductive disorders has been associated with extensive endocrine-disrupting chemical (EDC) exposure. Acrylamide (AA) is a compound formed spontaneously during heat processing of some foods that are mainly consumed by children and adolescents. In this study, we evaluated the prepubertal AA exposure effects on male adult reproductive physiology using a prepubertal experimental model to analyze the pubertal development, spermatogenesis hormones levels and genes expression involved in male reproductive function. This study is the first one to use the validated protocol to correlate the AA exposure with puberty development, as well as the AA-induced endocrine disrupting effects on reproductive axis. AA did not affect the age at puberty, the reproductive organ's weight and serum hormonal levels. AA reduces spermatogenesis, induces morphological and functional defects on sperm and alters transcript expression of sexual hormone receptors (Ar and Esr2), the transcript expression of Tnf, Egr2, Rhcg and Lrrc34. These findings suggest that excessive AA consumption may impair their reproductive capacity at adulthood, despite no changes in hormonal profile being observed.

Uncertainty of measurement and clinical value of semen analysis: has standardisation through professional guidelines helped or hindered progress?

This article suggests that diagnostic semen analysis has no more clinical value today than it had 25-30 years ago, and both the confusion surrounding its evidence base (in terms of relationship with conception) and the low level of confidence in the clinical setting is attributable to an associated high level of 'uncertainty'. Consideration of the concept of measurement uncertainty is mandatory for medical laboratories applying for the ISO15189 standard. It is evident that the entire semen analysis process is prone to error every step from specimen collection to the reporting of results and serves to compound uncertainty associated with diagnosis or prognosis. Perceived adherence to published guidelines for the assessment of sperm concentration, motility and morphology does not guarantee a reliable and reproducible test result. Moreover, the high level of uncertainty associated with manual sperm motility and morphology can be attributed to subjectivity and lack a traceable standard. This article describes where and why uncertainty exists and suggests that semen analysis will continue to be of limited value until it is more adequately considered and addressed. Although professional guidelines for good practice have provided the foundations for testing procedures for many years, the risk in following rather prescriptive guidance to the letter is that unless they are based on an overwhelmingly firm evidence base, the quality of semen analysis will remain poor and the progress towards the development of more innovative methods for investigating male infertility will be slow.

Effect of Sperm Morphology on Pregnancy Success via Intrauterine Insemination: A Systematic Review and Meta-Analysis

PURPOSE

Men with abnormal sperm morphology are often counseled that natural conception and intrauterine insemination are ineffective, and in vitro fertilization is the only option. Our objective was to determine the effect of sperm morphology on the pregnancy success of intrauterine insemination.

MATERIALS AND METHODS

We systematically searched for studies published prior to January 2017 that 1) reported ultrasound verified clinical pregnancies per intrauterine insemination cycle, 2) assessed sperm morphology using the Kruger strict criteria and 3) described morphology at the greater than 4% and 4% or less and/or the 1% or greater and less than 1% thresholds. In all studies mean female age was between 25 and 40 years and mean total motile sperm count was greater than 10 million. Estimates were pooled using random effects meta-analysis.

RESULTS

Data were extracted from 20 observational studies involving a total of 41,018 cycles. When comparing men at the greater than 4% and 4% or less thresholds, the rate of ultrasound verified pregnancy per intrauterine insemination cycle was not statistically or clinically different (14.2% vs 12.1%, p = 0.06) and the risk difference was 3.0% (95% CI 1.4-4.6), indicating 3.0 additional pregnancies per 100 intrauterine insemination cycles. When comparing men at the 1% or greater and the less than 1% thresholds, there were no statistical or clinical differences in the rate of ultrasound verified pregnancy per cycle of intrauterine insemination (14.0% vs 13.9%, p = 0.97) or in the risk difference (1.6%, 95% CI -4.5-7.6).

CONCLUSIONS

There appears to be no clinical difference in intrauterine insemination pregnancy success among men with normal and abnormal sperm morphology when accounting for total motile sperm count and female age. Abnormal sperm morphology alone should not exclude couples from attempting intrauterine insemination.

Men with a complete absence of normal sperm morphology exhibit high rates of success without assisted reproduction

In couples with infertility, abnormal strict morphology of 0% normal forms (NF) is a criterion to proceed rapidly to in vitro fertilization (IVF). Since no data currently exist, we investigated the outcomes for men with 0% NF to determine reproductive success without the use of assisted reproductive technologies (ART). A cohort of 24 men with 0% NF were identified (2010-2013) with 27 randomly selected men with ≥4% NF as controls. Patient charts were reviewed with men contacted and administered an Institutional Review Board (IRB)-approved telephone questionnaire to ascertain outcomes. After a median follow-up time of 2.5 years, 29.2% of men with 0% NF did not require ART for their first pregnancy (controls = 55.6%, P ≤ 0.05). When all pregnancies were analyzed together, men with 0% NF achieved twenty pregnancies of which 75% did not require IVF (controls = thirty pregnancies; 76.7% did not require IVF). The average age of men and female partners was similar between men with 0% NF and ≥4% NF. All men had normal follicle-stimulating hormone (FSH), testosterone, prolactin, sex hormone-binding globulin (SHBG), and estradiol. Although, global semen parameters were worse in men with 0% NF, when a first pregnancy was a natural conception (NC), 100% of men with 0% NF (n = 7/7) and 37.5% of controls (n = 3/8) went on to have a subsequent pregnancy via NC. Men with 0% NF conceived without IVF in 29.2% of cases compared to 55.6% of controls. Strict morphology should not be used to predict fertilization, pregnancy, or live birth potential. In men with 0% NF, alternative modalities should be considered before immediate IVF.

Role of Abnormal Sperm Morphology in Predicting Pregnancy Outcomes

The evaluation of strict morphology for predicting successful pregnancy has been controversial, nevertheless remains an essential component of semen analysis. Patients with teratozoospermia (abnormal strict morphology) have traditionally been counseled to undergo assisted reproduction. However, recent studies suggest that patients with abnormal sperm morphology alone should not be precluded from attempting natural conception before undergoing assisted reproduction. The goal of this review is to provide an update on the evaluation of sperm morphology for prognosis in assisted reproductive techniques such as intrauterine insemination and in vitro fertilization with or without intracytoplasmic sperm injection. Additionally, we propose a logical approach to the evaluation of a patient with teratozoospermia seeking fertility treatment.

Outcomes of Intracytoplasmic Sperm Injection Cycles for Complete Teratozoospermia: A Case-Control Study Using Paired Sibling Oocytes

OBJECTIVE

To investigate the outcomes of intracytoplasmic sperm injection (ICSI) cycles where sibling oocytes from a single donor were split between two recipients based on strict sperm morphology.

METHODS

Retrospective cohort study. All ICSI cycles had one donor's oocytes split between two recipients in a 1 : 1 ratio based on strict sperm morphology, that is, one male partner had morphology of 0% and the other had morphology of >1%. Fertilization, positive hCG, clinical pregnancy, spontaneous miscarriage, and live birth rates of the aforementioned groups were compared.

RESULTS

The baseline characteristics of the two groups (n = 103), including semen parameters of the male partners, were comparable. There was no difference in the fertilization rates when comparing the 0% group to the >1% group (78.7% versus 81.6%; P = 0.66). The overall positive hCG, clinical pregnancy, spontaneous miscarriage, and live birth rates for the 0% group were 61.2%, 49.5%, 10.7%, and 38.8%, respectively. The corresponding rates in the >1% group were positive hCG (63.1%), clinical pregnancy (55.3%), spontaneous miscarriage (7.77%), and live birth (46.6%).

CONCLUSIONS

The fertilization and pregnancy outcomes of ICSI cycles for strict sperm morphology of 0% versus morphology of >1% are equivalent. These results can provide reassurance to couples undergoing ICSI for severe teratospermia.

Isolated abnormal strict morphology is not a contraindication for intrauterine insemination

This study sought to investigate whether isolated abnormal strict morphology (<5% normal forms) and very low strict morphology (0-1% normal forms) affects pregnancy rates in intrauterine insemination (IUI). This was a retrospective study performed at an Academic Medical Center/Reproductive Medicine Center. Four hundred and eight couples were included for 856 IUI cycles. 70 IUI cycles were performed in couples with abnormal strict morphology and otherwise normal semen parameters. Outcomes were measured as clinical pregnancy rate per IUI cycle as documented by fetal heart activity on maternal ultrasound. Clinical pregnancy rate did not significantly differ between the group with abnormal strict morphology [11/70 (15.7%)] and the normal morphology group [39/281 (13.9%)]. Additionally, there was no significant difference between the pregnancy rate in the abnormal morphology group compared to that of our overall institutional IUI pregnancy rate [145/856 (16.9%)]. Furthermore, there was no significant difference between pregnancy rate in the very low morphology group [3/14 (21.4%)] compared to those with normal morphology or the overall IUI pregnancy rate. Patients with isolated abnormal strict morphology have clinical pregnancy rates similar to those with normal morphology for IUI. Even in those with very low normal forms, consideration of IUI for assisted reproduction should not be excluded.

Variants in DPF3 and DSCAML1 are associated with sperm morphology

PURPOSE

Abnormalities in semen parameters are often associated with reduced fertility in males, and may, in part, be attributed to genetic variation. Aim of this study is to determine if genetic variants that were previously shown to be predictors of family size and birth rate in healthy men are also associated with sperm morphology in men recruited from an infertility laboratory.

METHODS

Genetic associations with sperm morphology phenotypes in 126 ethnically diverse men from Chicago at 41 independent loci, previously shown to be predictors of family size and birth rate in healthy men, were tested.

RESULTS

Two intronic SNPs, rs680730 (in DSCAML1) and rs10129954 (in DPF3), were associated with the percent of normal sperm morphology in Chicago men (P = 0.017 and 0.023, respectively). Furthermore, both loci were associated with increased occurrence of sperm head defects.

CONCLUSIONS

SNPs in two genes, both of which have roles in nervous system development, were associated with poor sperm morphology. These results may be helpful in identification of other novel genes and biological pathways whose proper functioning is crucial for sperm production and male reproductive processes.

Sperm morphology classification: a rational method for schemes adopted by the world health organization

Sperm morphology is an important measure of testicular health, spermiation, and fertility potential. The World Health Organization (WHO) Semen Manuals advocate different sperm morphology schemes, but, like the schemes themselves, do not describe classification sequence or rules that can be unambiguously applied in a standard method. Our novel dichotomous key provides a rational decision framework for a sperm morphology classification algorithm. Classification order hierarchy is standardized and sperm characteristics are defined. Normal morphology is derived after eliminating abnormal and borderline normal forms. By defining and categorizing borderline normal forms separately from either normal or abnormal, the method can simultaneously produce results for Strict and traditional morphology schemes as adopted by different versions of the WHO Semen Manuals. The algorithm can be used for "recalibration" to a less stringent and potentially more relevant standard of normal, while reducing shift, drift, and variation in classification within and among analysts.