AF question

benandemilyb

(wasn't positive where to post this, but health seemed to be the best option)

I have heard that the time from your period to your ovulation is always the same (may not be the same from ovulation to period though).  I was wondering if any of you knew 1) if this is correct and 2) if it stands for post pregnancy while still BFing.  I know it can take a while for the hormones to "level back out" and I didn't know if I just need to be patient or what.

I started my period when DD was almost 5 months, still EBF, and I've been semi-regular since (she's almost 9 mo).  I'm trying to calculate because we don't want to use birth control, we don't want to use condoms ALL the time, and we don't want another baby quite yet.

Any help or advice is appreciated!