Comparing the Multi-ZSC one-step standardized swim-up method to the double-wash swim-up method with regard to the effects of sperm separation on morphology, head morphometry, and acrosome reaction inducibility

Human live spermatozoa morphology assessment using digital holographic microscopy

Digital holographic microscopy (DHM) was applied for the morphological assessment of live intact spermatozoa from fertile and infertile men directly after semen liquefaction. This method allowed us to study the sperm population directly from the sample droplet and not only from the focal plane of the microscope as in classical optical microscopy. The newly implemented 3-dimensional sperm morphological parameters (head height, acrosome/nucleus height, head/midpiece height) were included in morphological assessment of semen samples from fertile and infertile individuals. The values of the 3D parameters were less variable in fertile men than for infertile ones. DHM was also used to compare the morphological profiles of spermatozoa after applying the “swim-up” and gradient centrifugation techniques. During selection, the most statistically significant differences were observed after separation with a Percoll gradient of 90% and a 60-min “swim-up” procedure versus ‘native’ unfractionated samples. This shows that the developed methodology can be efficiently used for the selection of morphologically sound spermatozoa. The motility type for each spermatozoon was also assessed. The results indicate that the extension of the number of morphological parameters with new 3D parameters and the simultaneous assessment of sperm motility may be valuable addition to sperm examination.

Comparison of the effect of different media on the clinical outcomes of the density-gradient centrifugation/swim-up and swim-up methods

Objective

Sperm must be properly prepared in in vitro fertilization (IVF)-embryo transfer (ET) programs in order to control the fertilization rate and ensure that embryos are of high quality and have appropriate developmental abilities. The objective of this study was to determine the most optimal sperm preparation method for IVF.

Methods

Patients less than 40 years of age who participated in a fresh IVF-ET cycle from November 2012 to March 2013 were included in this study. Poor responders with less than three mature oocytes were excluded. Ham's F-10 medium or sperm-washing medium (SWM) was used in combination with the density-gradient centrifugation/swim-up (DGC-SUP) or SUP methods for sperm preparation. A total of 429 fresh IVF-ET cycles were grouped according to the media and methods used for sperm preparation and retrospectively analyzed (DGC-SUP/Ham's F-10, n=82; DGC-SUP/SWM, n=43; SUP/Ham's F-10, n=181; SUP/SWM, n=123).

Results

There were no significant differences among these four groups with respect to the mean age of the female partners, duration of infertility, number of previous IVF cycles, and retrieved oocytes. We determined that both the DGC-SUP and SUP methods for sperm preparation from whole semen, using either Ham's F-10 or SWM media, result in comparable clinical outcomes, including fertilization and pregnancy rates.

Conclusion

We suggest that both media and both methods for sperm preparation can be used for selecting high-quality sperm for assistive reproductive technology programs.

Assessing human sperm morphology: top models, underdogs or biometrics?

The assessment of the percentage of spermatozoa having an 'ideal' morphology using so-called strict method is the method recommended in the latest edition of the World Health Organization (WHO) laboratory manual for semen analysis. This recommendation is a result of the statistical association between 'ideal' sperm morphology and fertility, and of the current general belief that sperm morphology assessment should be used primarily as a fertility tool. The notion of an 'ideal' sperm morphology has persisted despite the very low percentage of such spermatozoa in the semen of fertile men, a subject of intense controversy. The detailed categorization of each abnormal spermatozoon has thus, for a long time, been considered optional and partially redundant, an idea which is reflected in the earlier editions of the WHO manual. However, several recent studies have shown the importance of carefully assessing abnormal sperm morphology for use in the diagnosis of infertility, to determine fertility prognosis, and for basic or public health studies. One approach, which combines videomicroscopy and computer vision, and is the only approach able to assess the continuum of sperm biometrics, has been used successfully in several recent clinical, basic and toxicology studies. In summary, the visual assessment of detailed sperm morphology-including the categorization of anomalies allowing arithmetically derived indices of teratozoospermia-and the more modern computer-based approaches, although often considered to be redundant, are in fact complementary. The choice of the most appropriate method depends on the field of investigation (clinical, research, toxicology) and the problem being addressed. Each approach has advantages as well as certain limitations, which will be discussed briefly herein.