That's a great tip--You are such an observant simmer, Play!
Guy: Excuse me, young lady, Pardon me for interrupting you while you hurl but I see your thought bubble shows baby blocks!
Girl: Bleccchhhh
Guy: Uh huh, my thoughts exactly. Would you like to try for baby?
To be serious, you mean that after one or more "Try for Baby" socials, the woman may show the blocks thought bubble while heaving so then our sim must pounce back on the poor woman?
The timing sounds tricky!