HIV, HPV and Chlamydia trachomatis: impacts on male fertility.

Sexually transmitted diseases (STDs) are pathologies that have viruses, bacteria, protozoa and fungi as infectious agents, affecting millions of people worldwide and causing physical and psychological consequences for the carrier. Some of these infections such as HIV, HPV and Chlamydia trachomatis may present an asymptomatic phase, making the diagnosis difficult, which is often only performed when the couple looks for infertility treatment after not achieving spontaneous pregnancy. Infertility affects 15% of couples, 50% of cases are male-related, and it is estimated that STDs, which interfere with the physiology of the male reproductive system and may impair semen in parameters such as motility, concentration, morphology and number, cause 15% of male infertility cases. Since STDs treatments are increasing the expectation and quality of life of infected patients, discussing issues such as sexuality and reproduction is of great importance in clarifying unknown facts. This paper aims to discuss how the infectious processes associated with HIV, HPV and Chlamydia trachomatis can interfere with semen quality causing male infertility without apparent cause.

Three-parent babies: Mitochondrial replacement therapies.

The mitochondria are intracellular organelles, and just like the cell nucleus they have their own genome. They are extremely important for normal body functioning and are responsible for ATP production - the main energy source for the cell. Mitochondrial diseases are associated with mutations in mitochondrial DNA and are inherited exclusively from the mother. They can affect organs that depend on energy metabolism, such as skeletal muscles, the cardiac system, the central nervous system, the endocrine system, the retina and liver, causing various incurable diseases. Mitochondrial replacement techniques provide women with mitochondrial defects a chance to have normal biological children. The goal of such treatment is to reconstruct functional oocytes and zygotes, in order to avoid the inheritance of mutated genes; for this the nuclear genome is withdrawn from an oocyte or zygotes, which carries mitochondrial mutations, and is implanted in a normal anucleated cell donor. Currently, the options of a couple to prevent the transmission of mitochondrial diseases are limited, and mitochondrial donation techniques provide women with mitochondrial defects a chance to have normal children. The nuclear genome can be transferred from oocytes or zygotes using techniques such as pronuclear transfer, spindle transfer, polar body transfer and germinal vesicle transfer. This study presents a review of developed mitochondrial substitution techniques, and its ability to prevent hereditary diseases.