I was in the very same situation when I was expecting our son. My hb dropped to well below 9 and the ferretin went down to 3. I was offered the infusions from about week 35 onwards and I am so glad I did. I had no side effects at all. It didn’t affect my UC like the normal tablets would and the increase in the energy levels was very welcome.
In the end I ended up having an emergency c-section, so I was so glad I had had those infusions. Also, no matter what sort of birth you have, you will be tired after the pregnancy & birth, and if your iron stores are low, it will be even harder to cope.
Personally I would definitely recommend getting them done.
Best of luck with the last few weeks now J