Can you have sleep apnea only in certain sleep positions?

Absolutely: Sleep apnea is more common in the supine position ( on your back). It is usually more common and more severe in deep REM sleep. Both of these facts are related to what happens to the tongue in both states. While on your back... The tongue is more likely to close the airway. In REM sleep most muscles in your body are relaxed. The tongue is a large muscle that relaxes and closes the airway.

Yes: Some people have apnea only when they sleep on their backs. Sleeping on your side can help and this has led to the recommendation of sewing a tennis ball into a pocket made in the lower back of a tee shirt. This can be used to train the wearer not to sleep on their back.

Yes: Most of the time if you have sleep apnea it shows in all position but in the case of mild sleep apnea some times in certain position like sleeping on your back you may see more symptoms of apnea such as snoring.

Sleep apnea: Hello. Yes, you could have positional sleep apnea that may only need measures to assure avoiding sleep in certain positions. Review these options with your sleep specialist

Yes: Yes. Most commonly on back where the effects of gravity cause the tongue to fall back and potentially block the airway. You sleep doc will help sort out this parameter.