You can always revisit the topic anytime with more detail. I told my main T about childhood trauma in stages,
1. taking vaguely about related subjects to gauge his reactions
2. talking around it, hinting that something happened to me
3. saying I want to talk about something but I don't know how
4. finally spitting it out but without detail
5. talking vaguely around it again
6. finally getting to details but only in small doses