Heartburn during pregnancy.
Heartburn is common during pregnancy, affecting 22% of women in the first trimester, 39% in the second and 72% in the third¹. This is because during pregnancy your body produces the hormone, progesterone, which slows down digestion and causes the muscular valve between the oesophagus and the stomach to relax, increasing the risk of gastro-oesophageal reflux.

As a result stomach acid is more likely to leak into the oesophagus and cause a burning pain in your chest and throat. Also, as your baby grows, the pressure on your stomach increases and this can force stomach acid into the oesophagus, again causing gastro-oesophageal reflux. Calcium-based antacids such as Rennie^® are used by over 50% of pregnant women to relieve heartburn symptoms and result in an 80% improvement in symptoms^2,3

Rennie^® is recommended as first time treatment for heartburn or indigestion in pregnancy as it works naturally within the stomach and oesophagus system onlyand does not enter into the mothers and baby's blood stream and harm the unborn baby^2,3

1: Source: Marrero JM, Goggin PM, de Caestecker JS, Pearce JM, Maxwell JD. Determinants of pregnancy heartburn. Br J Obstet Gynaecol 1992;99: 731-4
2: Broussard, C. N. and J. E. Richter (1998). ?Treating gastro oesophageal reflux disease during pregnancy and lactation: what are the safest therapy options? Drug Saf 19(4): 325-337.
3: Thomas, M. and S. M. Weisman (2006). Calcium supplementation during pregnancy and lactation: effects on the mother and the fetus. Am J Obstet Gynecol 194(4): 937-945.

Always read the label.
If symptoms are severe or prolonged, you should consult a doctor or pharmacist.