Low HCG levels usually mean the baby is either not as far as long as first thought or the baby isn’t doing well and a miscarriage might happen. Serum HCG levels have to be taken at least 3 days apart. HCG level should double every 2-3 days. HCG levels only increase until about week 12 and then start going back down again.
I have HEDS and have been pregnant 20 times, with 8 miscarriages (one in the second trimester, the rest in the first trimester). We are blessed with 13 living children (one pregnancy was natural fraternal twins – so got a bonus baby!). It was frustrating that no one would do anything about my chronic miscarrying (one pregnancy they thought for sure I would lose due to heavy bleeding. Went on bed rest for a month and that baby made it) until I had had 8 miscarriages. Then, my new OB looked at my progesterone level and found it to be too low for early pregnancy, so started me taking progesterone for the first trimester. My last two pregnancies ended up making it and I believe that was due to the progesterone. I’m not sure that any of that can be pinned on HEDS or not.
What did happen to me that is HEDS related is that my cervix would dilate very prematurely. After spending months on bed rest in the last trimester a couple times, I realized it would thin and dilate, but my water wouldn’t break and I never went into labor. On the contrary, I never really ever went into labor on my own. Had to be induced. That was especially frustrating after months of bed rest to keep baby “in”. Even my twins had to be induced at 38 weeks cause I was just too huge to keep going (they were 7 lbs each).
Totally agree with high protein during pregnancy!