Female infertility can be caused by viruses

This virus is present in 43% of women, for unknown reasons, the mucous membrane of the uterus is not able to conceive, but not in fertile women. The study is published in the journal PLOS ONE.

We are talking about the virus HHV-6A, which opened in 1986, but since then little has been studied. Since infection by this virus are usually asymptomatic, and its presence is difficult to detect in the blood or in saliva, so it is not known how it is distributed among the population. It is known that it closely related virus, HHV6-B, infecting nearly 100% of the population in early childhood and is transmitted through saliva.

Researchers from the University of Ferrara analyzed samples of endometrial tissue (the mucous membrane of the uterus), 30 women with infertility, the causes of which are unknown, and 36 women who gave birth. In 43% of samples from infertile women, found HHV-6A virus, while it was not in fertile women samples.

Scientists have also speculated that the cause of infertility can not be the virus itself, but the reaction to it of the immune system. The survey showed that the virus activates immune cells in the uterus, usually attack foreign agents that produce specific chemicals - cytokines. Activated immune cells and abnormally high levels of cytokines produce in utero environment unfavorable to the attachment of the fertilized egg cell, resulting in its rejection.

If the data will be able to confirm, will be able to help many infertile women, said the professor of the School of Medicine at Harvard University Comaroff Anthony (Anthony Komaroff), who specializes in studying the virus HHV-6.

Medications aimed specifically against the virus HHV-6A and HHV-6B does not exist yet. However, according to a press release from the Foundation for the Study of HHV-6 virus, it is possible that in this case may be effective are existing drugs for the treatment of cytomegalovirus which also belongs to the family of herpes viruses.

On average reproductive age women negatively affect the violation of so-called "circadian hygiene" - a bright light in the dark, work at night, the change of time zones, and so on. Help can conceive the restoration of normal circadian rhythms of day and night shifts.

Such an assumption is made by American and Japanese scientists on the basis of the data obtained in the course of experiments on laboratory mice. The study is published in the journal Cell Reports. It is known that many physiological processes in the body are subject to natural circadian rhythms (biological clock). Previous studies have shown that mammalian menstrual cycles and circadian rhythms are controlled by the same brain region - the suprachiasmatic nucleus. This has led researchers to suggest the existence of connection between the "breakdown" of the biological clock and age-related changes in reproductive function.

In experiments on mice, scientists found that young animals no artificially imposed violation of circadian rhythms do not act, their reproductive function is always normal. What can be said about older animals, which as a result of such manipulations are fruitless. However, as emphasized by the study's authors, it is very important that the violations were caused reversible - restore the normal rhythm of day and night, and restores the ability to reproduce.

"In today's society, women are less aggressive action of environment, they will inevitably have a negative impact on fertility - a bright light in the dark, work at night, the change of time zones, and so on, - said one of the study's authors, Gene Block (Gene Block) from the University of California. - The fact that we are using the normal schedule of the day and the night shift was able to restore fertility in female mice, suggesting an important role of "circadian hygiene" in this area. Reducing the level of illumination in the evening, eating at the same time, refusing to work or entertainment at night, sleeping and waking schedule - all these measures may help to cope with infertility. "