HELP ‼️ Iron deficiency 🩸 Pregnancy 🤰🏼

At my 27 week appointment when I did the glucose test and they took my blood they said my iron was low and they gave me a prescription for a daily iron supplement. I haven’t taken it yet because every time I take anything with iron in it it makes me constipated they switched me from a prenatal vitamin to a gummy and the gummy doesn’t constipate me but I know if I take the iron supplement it will. I told them this and they said “just drink plenty of fluids” I drink water all day it’s a regular thing for me but I still get constipated when I take iron. Ive always been anemic even before pregnancy. Is there any way I can avoid getting constipated but still make sure that my baby is healthy and getting all the nutrients he needs from me?