just to back up loopyc, my GP told me I could safely take Gaviscon whilst pregnant, I suffered with dreadful heartburn when pregnant with my first child. Hope you get relief soon
As everyone has said, Gaviscon is the best answer and get it free with a prescription and your medical card. But for a quick fix (ie. if out and about or at work) I found that a fizzy drink helped indigestion and milk is a godsend for heartburn.