Heartburn (acid reflux) and Indigestion in pregnancy

Unfortunately heartburn and indigestion are a common problem during pregnancy but what things are suitable to take during pregnancy which won’t effect your blood sugar levels? Gaviscon and Sugar Free Rennies. If these do not work then your GP may prescribe Omeprazole. All these products are suitable for use during pregnancy with gestational diabetes.

Many women suffer from both heartburn (acid reflux) and indigestion during pregnancy and it tends to become more common as the pregnancy progresses. In fact, by the third trimester, nearly three-quarters of pregnant women can suffer from heartburn. We take a look at the causes and symptoms of heartburn during pregnancy and explore a few options for treating this uncomfortable condition.

Causes of heartburn in pregnancy

There are two main reasons why heartburn and, to a lesser extent, indigestion are common at this time:

  1. The surge in the hormone progesterone causes muscles to relax. This includes the sphincter (ring of muscle) at the entrance to the stomach. When this relaxes, stomach acids are able to travel back up into the oesophagus (food pipe) causing heartburn.
  2. During the latter stages of pregnancy symptoms can also be caused by the baby physically putting pressure on the woman’s digestive tract.

Off the shelf products for heartburn and indigestion

Gaviscon​1​ contains no sugar and will not raise blood sugar levels and is safe for use in pregnancy​2​.

Rennies​3​ can be used, but be careful to select the sugar free version.

You’ll be relieved to know that all Rennie products are suitable for use during pregnancy (if taken as instructed and if prolonged intake of high dosages is avoided). Rennie’s antacid-based calcium carbonate and magnesium carbonate formula acts physically rather than by entering the bloodstream, neutralising excess acid and turning it into water and other natural substances that are easily evacuated by the body.

Rennie, Heartburn in Pregnancy

Milk for heartburn

It is not recommended to drink milk to reduce heartburn, as milk temporarily reduces the symptoms only to later increase acid production by the stomach, which causes more heartburn.

Heartburn caused by gestational diabetes diet

Some women find that changing to a gestational diabetes diet may cause an increase in heartburn and indigestion symptoms, especially if they are introducing a lot of higher fat foods as per the GD UK Diet.

If you feel the changes in diet are causing you these symptoms, try pairing foods with lower fat foods and other natural fats, especially if you feel you have been relying on a lot of high fat dairy products such as cheese and cream. Try to opt for plant based natural fats for a few days, such as avocado, olives, nuts and seeds for pairing to see if this helps ease symptoms, alongside leaner cuts of meat and white fish.

nutritional ketosis


Gastroesophageal reflux disease (GERD) occurs when stomach acid frequently flows back into the tube connecting your mouth and stomach (esophagus). This backwash (acid reflux) can irritate the lining of your esophagus.

Many people experience acid reflux from time to time. GERD is mild acid reflux that occurs at least twice a week, or moderate to severe acid reflux that occurs at least once a week.

Most people can manage the discomfort of GERD with lifestyle changes and over-the-counter medications. But some people with GERD may need stronger medications or surgery to ease symptoms.​4​

In a meta-analysis of 9 articles, (9067 patients and 81,968 controls) found a strong association between diabetes and GERD​5​, however the studies did not include or specify patients with Gestational Diabetes.

  1. 1.
    Heartburn During Pregnancy, Gaviscon . Heartburn During Pregnancy. Published 2021. Accessed April 23, 2021. https://www.gaviscon.co.uk/heartburn-pregnancy/
  2. 2.
    Strugala V, Bassin J, Swales VS, Lindow SW, Dettmar PW, Thomas ECM. Assessment of the Safety and Efficacy of a Raft-Forming Alginate Reflux Suppressant (Liquid Gaviscon) for the Treatment of Heartburn during Pregnancy. ISRN Obstetrics and Gynecology. Published online November 4, 2012:1-6. doi:10.5402/2012/481870
  3. 3.
    Heartburn in Pregnancy, Rennie. Heartburn in Pregnancy. Published 2021. Accessed April 23, 2021. https://www.rennie.co.uk/heartburn-during-pregnancy
  4. 4.
    Gastroesophageal reflux disease (GERD), Mayo Clinic. Gastroesophageal reflux disease (GERD). Published 2021. Accessed April 23, 2021. https://www.mayoclinic.org/diseases-conditions/gerd/symptoms-causes/syc-20361940
  5. 5.
    Sun X-M. Association between diabetes mellitus and gastroesophageal reflux disease: A meta-analysis. WJG. Published online 2015:3085. doi:10.3748/wjg.v21.i10.3085