**Author details**

majority of microcolonies were attached to squamous epithelial cells, whereas some were

Moretti et al. [101] examined ejaculate samples from infertile patients and detected *Enteroccocus faecalis* and *Escherichia coli* most frequently and, at lower frequencies, *Streptococcus agalactiae*, *Ureaplasma urealyticum*, *Staphylococcus epidermidis*, *Streptococcus anginosus*, and *Morganella morganii*. With the exception of *U. urealyticum*, the microorganisms are classed with the nonspecific saprophytic microflora and are not addressed in a conventional testing of infertility

Bacteria may damage spermatozoa even in the absence of an overt inflammatory reaction. We observed higher contents of acrosome-reacted spermatozoa (i.e., those with a premature acrosomal reaction) in the ejaculate samples that contained bacterial microcolonies [55].

Despite the success of molecular biology, the morphological methods of research continue to

**1.** Idiopathic infertility with normozoospermia or with small deviations in the semen parameters (revealing anomalies of spermatozoa that are not visible in the traditional spermio-

**2.** Examination of patients whose wives had a history of miscarriage due to abnormal embryo development, such as non-developing pregnancy or spontaneous abortion in the first

**3.** Differential diagnosis of genetically determined and functional forms of asthenozoo-

Testing for ultrastructural sperm abnormalities makes it possible not only to identify the cause of infertility but also to choose proper clinical tactics, that is, to select treatments, to

This work was supported by the Russian Science Foundation (project no. 14-50-00029) and the Russian Foundation for Basic Research (project no. 16-04-01447) and by Moscow State

recommend ART using own spermatozoa, or to offer ART using donor sperm.

play a considerable role in determining the reasons of male subfertility and infertility.

associated with sperm heads or tails (**Figure 9a**–**d**).

Indications for the studies using TEM are as follows:

trimester of natural pregnancy or ART failure.

spermia and teratozoospermia.

University Development Program PNR5.13.

**Acknowledgements**

patients.

**7. Conclusion**

90 Spermatozoa - Facts and Perspectives

logical study).

Elizaveta E. Bragina1 \* and Elena N. Bocharova2

\*Address all correspondence to: bragor@genebee.msu.ru

1 Department of Electron Microscopy, AN Belozersky Institute of Physico-Chemical Biology, MV Lomonosov Moscow State University, Moscow, Russia

2 Moscow Scientific and Practical Center of Dermatology, Moscow, Russia
