I'm just wondering if this is a triphasic chart.
It could be, but there's not a really clear 3rd level of temps. Keep in mind that you can be pg and not have a triphasic chart...or have a triphasic chart and not be pg. So you're still in the running at this point :-)
SueHomeschooling mom to DD15 & DS11
CL of Homeschooling, Signature Showcase, Ectopic Loss, and Fertility Charting