High-altitude hiking, sleep apnoea and other conditions which deprive a man's testes of oxygen, could be contributing to a decline in fertility over the past 50 years, a new study has suggested.

The immediate effects of low oxygen on sperm quality are temporary, but new evidence suggests that a long-term decrease in ...

Medical conditions that deprive the testes of oxygen, such as sleep apnea, may be contributing to the decline in male fertility observed over the past 50 years, a new study suggests.

A lack of oxygen in the testes, or testis hypoxia, caused by chronic medical conditions -- such as sleep apnoea or varicocele -- can be a sustained threat to reproductive health, lead author, Tessa ...

and are now carried on most major high altitude expeditions. Bags can be rented for short term trips such as treks or expeditions. Above 10,000 feet (3,000 meters) most people experience a periodic ...

High altitude pulmonary edema, or HAPE ... "If a climber is trying to reach 14,000 feet, once they get to 10,000 feet they should not stop and sleep any higher than 11,000 feet the first night, 12,000 ...