I can only imagine that there are a number of secondary effects of creating a skewed male/female ratio.

Simply put, there are not enough women to go around.

I suspect this leads to lots of overly fierce competition for women. Women treated more as precious commodities and less as human beings. Men lacking experience dealing with women. A certain percentage of men being unhappy much of the time because finding a mate is frustrating, or they've simply given up on it.

This is only conjecture but it's hard to imagine it being otherwise.