Hi, Thanks for using Healthcaremagic, You are pregnant and in pregnancy iron requirement is increased so it is routine to supplement iron tablets. Usually other important vitamins like folic acid are combined.If one salt like ferrous sulphate is not tolerated other salt can be used with the consultation of your Gynecologist. Please report it to your doctor she will suggest you with prescription. If iron are not tolerated orally then injectable iron can be given intravenous or intramuscular route. please also enrich your diet with natural sources of iron and ingestion of vitamin c helps in absorption of iron. Hope this helps. Take care. Good Luck. Dr.Akhilesh Dubey M.D.