Hi Preeti you should not take both together because calcium hinders iron absorption which is very important. Eat iron in the morning after breakfast and calcium in the night after dinner. Iron not in the night because it slow downs the digestive system which is already slow because of pregnancy harmones hence it will result in constipation. Also when you have iron have it with lemon juice or orange juice it will help to absorb the iron to the body.

You can take together... Why don't you eat in the morning after breakfast

Calcium you take in morning with breakfast and iron tablet you take at evening