Help me figure this out please

[SamiPolizzi]

I recently found out I'm pregnant. I'd like to figure out the exact day I conceived. The only two possible days would have been CD 9 and CD 19. My cycle is always either 31 or 32 days. 

Which day would have been more likely? Or is this not enough info to be able to tell?

[AdinaL]

Just based on the numbers you have given, I would say day 19 was probably more likely.

[begoniamama]

since it totally depends on when you ovulated, and you're not sure, it's hard to tell. with a 31/32 day cycle your ovulation day (and window) is probably closer to day 19 then day 9. most healthy luteal phases (phase from O day to AF) are at least 11 days, so you could ovulate as late as day 20, but i think it's more likely that you conceived on day 19.

i personally have 29/30 day cycles when i'm menstruating and I pretty much always ovulate on day 15. 

[SamiPolizzi]

Ah! I'm so confused now! I've had a couple friends tell me it was probably day 9, because if I ovulated on day 14 or 15, the sperm could still be hanging around. 

I guess it doesn't really matter. I'm not going to get too hung up on a due date anyway. 

[begoniamama]

but ovulating on day 14 is assumed for a 28 day cycle, and rarely do women actually have 28 day cycles exactly with exactly day 14 ovulation. your cycle is about 4 days longer (32), so if you were going by the assumption that you ovulate halfway through your cycle, that would be around day 16 - which is closer to day 19.