Talk to Gynecologist on Sugar Level Increased After Iron Infusion. 30 Weeks Pregnant

Aoa doctors, my 8th month just started 3 days back. i was having low hb and rbc so my gynaecologist prescribed me venofer injection. total 6 injections, 2 injection in each drip of NS. i had borderline OGTT which i was maintaining with diet and walk. It used to be below 110 after 1 hour of every meal. I got my first iron infusion on 30th june. Next day my sugar after 1 hour of breakfast was 140 and 168 1 hour after lunch. i took glucophage 250 before dinner. Next day i took glucophage thrice before meals and BSL remained 117 118 120. Still taking medicine to control sugar and i took my 2nd iron drip on 2nd july but now my sugar levels are higher after lunch. 136 even after medicine. i want to know is iron drips are effecting my sugar level as i haven't change anything in my diet. its totally same. no artificial sugar less carbs and walk. The only change in my routine is venofer injections. please guide me should i get my 3rd dose ? and what can be reason of sudden increase in BSL. THAN