I'm going to jump on board too, even though I don't hit 13 weeks until tomorrow. I was originally told 12w1d was the start of the second trimester, and for the purposes of medication management (I have severe fibromyalgia) 12 weeks is a critical point.
...that, and I started feeling the legendary second trimester energy burst yesterday.

I've been cooking, cleaning, and working non-stop for two days now. It's a little scary how much I'm getting done all of a sudden, after three months of dragging myself around and getting further and further behind every day. The nausea is pretty much gone too (although I've still got some odd food aversions) so I'm starting to think this pregnancy thing isn't so bad after all.
So maybe I'm technically still in the first trimester, but whatever - I feel better!
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