"will cause" is incorrect. There is no genuine evidence for poor sperm quality, excessive anxiety unregulated blood pressure or "others" like what the psychosis myth?
We know from Professor David Nutt the facts regarding any negatives and they have been consistently exaggerated ever since his findings which cost him his job in Tony Blairs government because he refused to exaggerate his own findings. You would need thousands of regular cannabis users over 5 years to produce just 1 case of psychotic related symptoms. Alcohol could do that to everyone within 1 year and actually cause fatalities.
I'm a regular cannabis medication user which helped me beat brain cancer which is what my normal blog is about. I suffered from anxiety through most of my 20's which only went away when I fed my endo-cannabinoid system. We also have a child on the way so I would love to see the logic/donor relations behind the author of these persistent theories.
We had a recent study in the UK that concluded: "95% of police cannabis seizures were high THC Skunk". It then turned out that 2 of the board members that funded this study were from GW pharmaceuticals who have a vested interest in keeping prohibition in place due to their license dominance for Sativex.
Rule of the thumb is to follow the money behind any study that wasn't conducted by Professor David Nutt when he was a government-appointed scientist to check for all the negative side effects to cannabis with the most robust budget ever used on such a study.