Many people will find that sleeping on their stomachs is easy to hiccup, which is mainly caused by the following reasons: 1. Sleeping on your stomach can easily lead to increased pressure in the thorax, which in turn compresses the gastrointestinal tract, causing gas in the gastrointestinal tract to be forced out through hiccups. 2. Sleeping on your stomach can easily cause pressure on the gastrointestinal tract, causing the diaphragm to spasm and hiccups. 3. The first thing you need to do is to get a good idea of what you’re doing. In this case, it is recommended not to sleep on your stomach, it is best not to eat too much, and after eating it is recommended to take a proper walk, stand, sit and rest for 10-20 minutes.