I had another appointment with the LC yesterday. The bad news is that Eli hadn't gained. The good news is, we think we've figured out the problem.
Our guess is that he has developed a lazy suck. I have a very strong let-down, so he would gulp that down and be satisfied. At least, that's what used to work until he had his last growth spurt. Now he's not getting enough fatty milk because he's not working for it. As a result, my supply dropped and he stopped gaining weight. I also have odd anatomy that makes it hard for him to draw the milk out - even when it looks like he's latched properly he's not deep enough. That's also why I have such a hard time pumping.
So with the use of a larger shield, larger pump horn and a supplemental nursing system, we're trying to get his weight up. The good news is that so far I've been pumping more than he's needed for a supplement. I go back in on Monday to see if what we're doing is working. If not, I'll need to supplement more (and right now I have some in the freezer for that purpose) and perhaps get a referral to a pediatrician to see if there is another reason for his not gaining.
Be praying my supply increases quickly - medication isn't really a possibility for me in that area because it has odd side effects for me (extreme mood swings). I'm doing everything I can with herbal remedies, hopefully they'll work. Also be praying Eli starts gaining and we don't need to use formula.