The role of paternal chromosomes and sperm morphology on the outcome of intracytoplasmic sperm injection

Influence of the type of semen and morphology of individual sperm cells on the results of ICSI in domestic cats

The aim of this study was to analyze the influence of the type of spermatozoa and of different sperm abnormalities on fertilization and embryo development after ICSI in cats. In Exp I, ICSI was performed using urethral or epididymal spermatozoa collected from 7 tomcats. In Exp. II, epididymal spermatozoa from 16 cats were used for ICSI and an epididymal spermatozoon exhibiting no abnormalities or one with an abnormality was microinjected into an oocyte. Exp. I was performed in 14 replicates and Exp. II was performed in 20 replicates. In both experiments the number of cleaved oocytes, the number of embryos at the morula stage and the number of embryos at the blastocyst stage were evaluated at 24 h, and at 6 and 7 days after ICSI, respectively, and compared between experimental groups. No statistically significant differences (P > 0.05) were observed, either for Exp. I or for Exp. II. The average cleavage rate was 60.2%, morula rate 62.3% and blastocyst rate 19.2% in Exp. I and 51.6%, 66.8% and 25.8% in Exp. II, respectively. The study confirmed that both urethral and epididymal spermatozoa can be used for in vitro fertilization in cats and proved the usefulness of the ICSI method in the case of teratozoospermic males. The study showed that even in severe cases, when almost no normal spermatozoa can be found in the semen, it is possible to obtain embryos using abnormal sperm cells with the same chance of success as for normal spermatozoa.

Availability, effectiveness and safety of ART in sub-Saharan Africa: a systematic review

STUDY QUESTION

What is the evidence pertaining to availability, effectiveness and safety of ART in sub-Saharan Africa?

SUMMARY ANSWER

According to overall limited and heterogeneous evidence, availability and utilization of ART are very low, clinical pregnancy rates largely compare to other regions but are accompanied by high multiple pregnancy rates, and in the near absence of data on deliveries and live births the true degree of effectiveness and safety remains to be established.

WHAT IS KNOWN ALREADY

In most world regions, availability, utilization and outcomes of ART are monitored and reported by national and regional ART registries. In sub-Saharan Africa there is only one national and no regional registry to date, raising the question what other evidence exists documenting the status of ART in this region.

STUDY DESIGN, SIZE, DURATION

A systematic review was conducted searching Pubmed, Scopus, Africawide, Web Of Science and CINAHL databases from January 2000 to June 2017. A total of 29 studies were included in the review. The extracted data were not suitable for meta-analysis.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The review was conducted according to Preferred Reporting Items for Systematic Reviews (PRISMA) guidelines. All peer-reviewed manuscripts irrespective of language or study design that presented original data pertaining to availability, effectiveness and safety of ART in sub-Saharan Africa were eligible for inclusion. Selection criteria were specified prior to the search. Two authors independently reviewed studies for possible inclusion and critically appraised selected manuscripts. Data were analysed descriptively, being unsuitable for statistical analysis.

MAIN RESULTS AND THE ROLE OF CHANCE

The search yielded 810 references of which 29 were included based on the predefined selection and eligibility criteria. Extracted data came from 23 single centre observational studies, two global ART reports, two reviews, one national data registry and one community-based study. ART services were available in 10 countries and delivered by 80 centres in six of these. Data pertaining to number of procedures existed from three countries totalling 4619 fresh non-donor aspirations in 2010. The most prominent barrier to access was cost. Clinical pregnancy rates ranged between 21.2% and 43.9% per embryo transfer but information on deliveries and live births were lacking, seriously limiting evaluation of ART effectiveness. When documented, the rate of multiple pregnancy was high with information on outcomes similarly lacking.

LIMITATIONS, REASONS FOR CAUTION

The findings in this review are based on limited data from a limited number of countries, and are derived from heterogeneous studies, both in terms of study design and quality, many of which include small sample sizes. Although representing best available evidence, this requires careful interpretation regarding the degree of representativeness of the current status of ART in sub-Saharan Africa.

WIDER IMPLICATIONS OF THE FINDINGS

The true extent and outcome of ART in sub-Saharan Africa could not be reliably documented as the relevant information was not available. Current efforts are underway to establish a regional ART data registry in order to report and monitor availability, effectiveness and safety of ART thus contributing to evidence-based practice and possible development strategies.

STUDY FUNDING/COMPETING INTERESTS

No funding was received for this study. The authors had no competing interests.

TRIAL REGISTRATION NUMBER

PROSPERO CRD42016032336

The influence of homogenous zona pellucida on human spermatozoa hyperactivation, acrosome reaction and zona binding

The study aimed to evaluate the changes in sperm motion characteristics and the occurrence of hyperactivation among sperm populations after exposure to human zona pellucida. Motile spermatozoa samples were used to evaluate the sperm-zona binding capacity, zona-induced acrosome reaction and changes in sperm motion characteristics. Sperm motion characteristic changes studied included straight line velocity, curvilinear velocity, amplitude of lateral head displacement, straightness and beat cross frequency. Recordings were performed on semen immediately after liquefaction, 3 h capacitation and after exposure to solubilised human zona pellucida. The semen samples were divided into morphology categories, namely six (16 +/- 1.4% normal forms, normal patterns), 31 (8 +/- 1.7% normal forms, G-pattern) and 27 (3 +/- 1.3% normal forms, P-pattern). The Hemizona Indices for the three morphology groups namely normal, G-patterns and P-patterns, were 77 +/- 6%, 61 +/- 5% and 41 +/- 5% respectively (P <or= 0.05). The zona-induced acrosome reaction for the three groups were 25.0 +/- 2% (normal group), 18.0 +/- 2% (G-patterns) and 14.1 +/- 0.6% (P-pattern) (P <or= 0.05). The number of hyperactivated sperm showed an increase in the ejaculates (1%), after capacitation (2%) and exposure to zona pellucida (5%) (P <or= 0.05). When divided into the three morphology groups, the number of spermatozoa with hyperactivated motility was more profound in men with normal morphology compared with G- and P-pattern men. Human zona pellucida is a strong inducer of hyperactivated motility among spermatozoa and the effect is more profound among sperm populations with normal morphology.