Right just had a quick check and rennie shouldnt be taken with NSAIDS (non steroidal antiiflammatory drugs) which are a group of painkillers which includes aspirin, ibuprofen and diclofenac.
Thats i assume cos it reduces and neutralises stomach acid and the acid prevents the nsaids causing gastric irritation.
However the aspirin dose for pain relief is 300mg and if you are taking what i was you are on 75mg and you are not meant to take any nsaids for pain relief during preg anyway
I used gaviscon/tums/remegel and then ended up on a gastric med called omeprazole and they were quite happy for me to take em together with the aspirin.
So id say go for it if it helps the only thig i do recall is non pregos can take 16 rennies a day but i think the amount for pregnant women is something like 7-9 so dont go nuts
Feel better xxx