Ovulation occurs once monthly. I presume you mean her temperature went down 1.2 degree after her ovulation, therefore leading you to believe she was no longer ovulating ("fertile"). While it is possible that she ovulated twice, there may very well be other reasons for her temperature to rise later in her cycle (i.e. a viral illness). I had a bit of trouble following your chonology of her cycle this month. I am presuming that she ovulated around day 12 and like I had mentioned, there are other possibilities for increased temperature. I would have get a pregnancy test to be on the safe side if she is "late". While the "rhythm" method of birth control is widely used, it is one of the least effective at preventing pregnancy (even when periods are regular). If her temperature stays UP like this, maybe a blood test would yield other possible causes.
I hope this helps!
<ul>
<li> The first half of a woman's cycle is dictated by Estrogen. temps are low to normal.
<li> There is a significant dip in temps on the day of ovulation. Ovulation typically (not always) happens 14 days <i>prior</i> to a woman's next period.
<li> The egg lives 12-24 at most. (Sperm lives up to 5 days in the fallopian tubes when under the right cervical fluid conditions).
<li> Once ovulation is over (12-24 hours), whether pregnant or not, the body releases Prosterone to ensure a stable pregnancy. Prosterone is necessary to sustain a pregnancy, so the body produces it at this time (post ovulation - PMS) "just in case". Progesterone dictates the second half of a woman's cycle.
<li> Progesterone heats up the body. The temps prior to ovulation will give a hint to post-ovulation temps. If her temp was 98.1 prior to ovulation (in the evening), it may be 99.1 during PMS.
<li> A woman is unable to ovulate twice, but is however able to release more than one egg during her ovulation window.
<li> A woman's temp drops signalling her period is about to arrive. If her temps stay high for 18 days in a row, its very possible that she is pregnant. Her temp will remain warm until delivery.
</ul>
I hope this was of some use to you. If there is anything you don't understand, please feel free to post to me directly.
Here is a BBT Guide if you are interested in monitoring temps:
<a href="http://www.am-i-pregnant.com/bbtguide.shtml">BBT Guide</a>
Best,
Anai Rhoads