You’re impugning the reputation of responsible men. Men who have vasectomies are certainly not more likely to be irresponsible. They are in fact being highly responsible. I hope you’re not expecting your wife to carry the entire contraceptive load. The very safest way to ensure a couple doesn’t conceive an unwanted baby is for the male to get a vasectomy. It’s hard to understand why you would resist such a thing so vehemently.