Mouth breathing can happen for different reasons. It could be out of habit, or it might happen occasionally because someone is experiencing a nasal obstruction, usually caused by being sick.

Breathing through your mouth will most likely affect your oral temperature so you may notice that your BBT readings are lower than usual. It’s pretty tough to correct for this but don’t worry, it shouldn’t significantly impact your ability to track. Simply make a note of it in Glow so you’ll remember why these temperatures seem a little strange. Otherwise, you should be able to interpret your chart and see your ovulation patterns. If you find that you’re still having trouble, consider your alternatives, like switching to vaginal readings, for better accuracy.

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