If your relationship balance and trust is based on whether or not your partner can secretly make babies with you without your consent, that is something to be addressed (in a human way, not by using ultrasound on your testicles).
As men, this is absolutely something that we should worry about.
> People often lie and act irrationally.
If that is your fundamental truth in interacting with your partner(s), your relationships will never really get anywhere. It is just not good advice to tell people to do so, unless you want them to never create meaningful connections with their partners.
I guess. I've never had reason not to be open about these issues and it's never disrupted trust in the relationship. I've discussed these ideas with every partner I've ever had. They weren't offended, they understood. Many even had their own stories of unplanned pregnancies to share.
My girlfriend lets me give her the trimestral birth control injections.