My sims wont try for a baby

This has happened in every single one of my sims saves. Every single sim. Their relationship will be high and be satisfied in their relationship, but whenever I ask to try for a baby they get angry at the sim who is asking and it decreases their romance. I'm not sure what to do or how to fix this. The only way I can get them pregnant is using the MC woohoo and have risky on. I've only started to have this issue around when Lovestruck came out.