No. It's always a blessing to enjoy sex with one's spouse, even when it will be naturally infertile (a few examples: during the infertile times of the cycle, during pregnancy, after menopause.) That's because one of the two essential meanings of sexual intercourse, is the sharing of sexual love as the expression of the marital bond. As the Catholic Church teaches.
Some of your fellow catholics post as if all sex that is NOT intended or could wind up leading to a pregnancy is sinful and wrong.
Perhaps they don’t mean to sound like that.