Is dry mouth an early sign of pregnancy?
Dry mouth is a common symptom during the first trimester, often becoming more severe at night [1, 2, 3]. It is usually accompanied by dry, stuffy nose, chapped lips, headaches, hot flashes, indigestion, and metal cotton mouth (bitter, metallic taste in the mouth). In some cases, the tongue may turn pale white that is more apparent when you wake up in the morning [4, 10].
What causes excessive thirst and dry mouth during pregnancy
- Pregnancy hormonal changes leading to reduced saliva flow, causing the mouth to become dry 
- Increased blood volume resulting in processing of extra fluids through the kidneys that lead to frequent urination, making you feel dehydrated and thirsty [1, 4, 7]
- Inadequate intake of water 
- Gestational diabetes [1, 6]
- High rate of metabolism causing excessive sweating, making your body lose more water, thus resulting in extreme thirst 
- Certain prescribed medications causing dryness in the mouth as a side effect 
Remedies to get rid of dry mouth in pregnancy
Since saliva helps in eliminating food debris from the mouth, its low production boosts the growth of oral bacteria, resulting in bad breath as well as tooth and gum infection [1, 3, 4]. Maintaining good oral hygiene provides protection from such conditions. Here are some tips to help treat and manage the problem:
- Drink enough water to keep your body hydrated .
- Have sugar-free lozenges, gums or candies for increasing the saliva flow in the mouth to prevent bad breath. However, you need to consult your doctor before using these products [3, 4].
- Follow a healthy diet consisting of diary products, nuts, carrots and other leafy green vegetables.
- Avoid sugary foods .
- Rinse your mouth with an alcohol-free mouthwash (you may consult your doctor to avoid any potential risks) .
- Brush your teeth twice a day with a soft-bristled toothbrush
- Reduce the consumption of tea, coffee, and soda as it might make the mouth dry, causing extreme thirst .
How long does dry mouth last during pregnancy
Since hormonal changes contribute to dryness in the mouth, in most women it usually goes away after childbirth.
When to call the doctor
Besides the symptoms of dry mouth and extreme thirst, if you are experiencing fatigue, nausea, vomiting , extremely frequent urination , dizziness and diarrhea  that refuses to go away, then get in touch with your physician [1, 6,8] as it might indicate gestational diabetes.
A blood glucose test is performed routinely during the second trimester of pregnancy (between 24 and 28 weeks) to detect the complication . In case, you have a history of gestational diabetes your doctor might recommend getting the test done between 16 weeks and 18 weeks .
Dry mouth ICD-9 and ICD-10 codes
The ICD-9 code for RLS is 527.7  while its ICD-10 code is K11.7  and R68.2 .[ref]
- http://www.parents.com/pregnancy/complications/gestational-diabetes/pregnancy-gestational-diabetes/ [/ref]