A new study found a link between sleep duration and a measure of chromosomal health in sperm . The findings are published in the Journal of Sleep Research .
In the study of 2020 semen samples provided by 796 male volunteers from colleges in Chongqing ( China) from 2013 to 2015, volunteers with more than nine hours per day of sleep and those with 6. 5 hours or less per day sleep had 41 per cent and 30 per cent lower High DNA Stainability — an index that represents the proportion of sperm with abnormal chromatin — than did volunteers with seven to 7. 5 hours per day of sleep . Chromatin is a complex of DNA and proteins that forms chromosomes .
“ This is new information after our previous finding that sleep duration has an inverse U -shaped association with semen volume and total sperm count . In the previous study , we found that these two semen parameters were highest when sleep is 7. 0 to 7. 5 hours per day , and either longer or shorter sleep was associated with the decrease of the two semen parameters , ” said Dr . Jia Cao , co-author of the study