Heartburn is a burning sensation felt in the esophagus and chest due to indigestion and reflux of stomach acids. Women often experience mild to moderate heartburn  during the early stages of pregnancy. It is quite common during the second and third trimesters as well.
Is Heartburn an Early Sign of Pregnancy?
It is counted among the earliest signs of pregnancy along with nausea, vomiting, food craving and aversions, dizziness and mood swings .
What Does Heartburn Feel Like?
- Burning sensation in the chest, behind the breastbone especially after eating 
- Burning sensation in the throat with a feeling of sour, hot, acidic fluid at the throat’s back
- Feeling of foods stuck in the middle of one’s throat or chest 
- Mild to moderate chest pain especially when lying down or bending over
- Chronic cough or sore throat
What Causes Heartburn in Pregnancy?
Causes during early pregnancy: The high levels of the hormone progesterone relax the valve between the esophagus and stomach. As a result, it is unable to close properly to prevent stomach acids from entering the esophagus and irritating the lining, causing heartburn 
Causes during later stages: The growing uterus is the main reason for the symptom, especially after the 20th week. It pushes the stomach against the diaphragm, causing the stomach contents to move into the esophagus. This leads to acid reflux and heartburn .
Foods that Cause Heartburn when Pregnant
- Alcohol (especially red wine)
- Fried and fatty foods 
- Black pepper
- Raw onions
- Avocado 
- Citrus fruits like oranges (or orange juice), tomatoes and grapefruits
- Chocolate 
- Coffee and caffeinated beverages like tea and soda
- Carbonated beverages
Tips for Preventing Heartburn While Pregnant
- Eating several small meals rather than three large ones 
- Eating slowly, chewing the food properly
- Drinking at least 8-10 glasses of water every day 
- Avoiding the common food triggers 
- Maintaining a certain activity level as prolonged inactivity (e.g. extended bed rest) can relax the muscles, worsening the symptom 
- Drinking less water during meals 
- Sitting upright in a high-backed comfortable chair instead of slouching
- Avoiding lying down or bending over directly after a meal
- Keeping the head and chest in a higher position than the rest of the body when lying down
- Wearing loose fitting clothes to reduce the pressure on the stomach
- Trying not to gain too much weight
- Avoiding smoking
Heartburn Relief during Pregnancy
Medicines for Severe Heartburn Symptoms during Pregnancy
Non-prescription antacids like TUMS can be safely used for getting rid of heartburn in pregnancy while they also provide certain nutrients (e.g. calcium) essential during pregnancy . Physicians strongly recommend avoiding antacids containing aluminum while sodium bicarbonate (or baking soda) and sodium citrate sold as antacid tablets should be avoided as well .
Apart from calcium containing antacids, a few other safe medications are:
- Ranitidine  (Zantac: pregnancy category B in US)
- Omeprazole (Prilosec: pregnancy category C in US)
One should consult her doctor before using any of the above medicines; otherwise, they may lead to various pregnancy-related problems. The following side effects  may occur in some rare cases:
Home Remedies to Cure Heartburn during Pregnancy
Here are some other ways to stop heartburn:
- Eating some yoghurt after each meal  (the probiotics found in yoghurt are believed to neutralize the stomach acids)
- Papaya (in any form)  as its digestive enzymes soothe the stomach
- Chewing gums  reduces the acid levels by encouraging saliva flow while the bicarbonate in gums helps to neutralize the refluxed acids.
- Drinking some milk (preferably cold) or having some ice cream before meals and whenever the symptom occurs 
- Taking a glass of warm milk mixed with a tablespoonful of honey 
- Having two teaspoonfuls of apple cider vinegar along with 8 oz water (add honey if desired) 
- Ginger (in any form)
- Taking 1-2 teaspoonfuls of mustard 
- Raw almonds
- Snacking on a fresh celery stick 
- Basil leaves
When to Call the Doctor?
It is advisable to call the doctor in case of the following symptoms along with heartburn:
- Constant heartburn 
- Difficulty swallowing
- Severe heartburn causing sleep disturbances
- Spitting up blood
- Excessive weight loss 
- Black stools
Myths Associated with Heartburn during Pregnancy
One myth says that if a woman suffers from heartburn during pregnancy, she is going to have a baby with a full head of hair . There is another myth saying one can find out if she is going to have a boy or girl depending on whether or not she has heartburn while pregnant. But in truth, these are just old wives tales as each pregnancy is different with different signs and symptoms.
Heartburn ICD-9 and ICD-10 Codes
Its ICD-9 code is 787.1 while the ICD-10 code used for heartburn is R12.[ref]
- http://tipnut.com/heartburn/ [/ref]