EU research suggests that PCBs damage sperm but finds no dramatic effect on male fertility
... men in the study were fertile. The probability of fathering a child starts to decrease when the proportion of damaged sperm reaches about 20% and becomes negligible from 30-40% onwards. "PCB exposure might negatively impact reproductive capabilities especially for men who, for other reasons, already have a hi...Like their pregnant mates, primate dads-to-be pack on pounds
...lp scientists better understand what governs human fathering behavior, Ziegler adds. "We're interested in what motivates dads to be good parents because there are so many men who just aren't good fathers. This work could help to tease apart what makes a good dad." In the last few decades, scientists have noted...Study shows that genetic quality of sperm deteriorates as men age
...older, increasing a man's risk of being infertile, fathering unsuccessful pregnancies and passing along dwarfis...d risk of infertility and a reduced probability of fathering a successful pregnancy. The study, "Advancing age has differential effects on DNA damage, chromatin ...