Dizzy and tired in 3rd trimester

[Starman]

Wife constantly tired despite 16 hours sleep per day and she's starting to fret about it. We're at week 32 now and already pleased with the Spatone, and already passed the blood test for diabetes etc. She is also very dizzy at times and she surprised everyone when she had to sit down in Sainsburys. We thought it was par for the course but we attended ante-natal class today and all other mums-to-be were all really chipper. It's not diet as all food is fresh and lovingly prepared.
What could we investigate next?

Iron levels?

Maybe she's having too much sleep or is anaemic? Also she should try and eat little and often.

I had this- I had low blood pressure and, although I didn't find out until long after the birth, an underactive thyroid.

Ask for blood tests for thyroid function, iron levels and take blood pressure.

anaemia? (spatone good but ferrous fumarate/ sulphate more effective- when was last FBC blood test?)

postural hypotension (lower BP when standing up than sitting down) ?

i think she should see the gp ASAP to get a few things checked out

good thought on thyroid

Thanks for the suggestions. Midwife was consulted and has recommended additional iron tablets as more effective than Spatone alone. The last few days seem to be better and we went out for a pleasant walk on Sunday without incident. I'm investigating thyroid and bp too - just to be sure. thx again