If you’ve ever felt a tingling, pins and needles sensation in your limbs, like when you cross your legs for too long or hold the same position without moving, you’re probably familiar with the discomfort of arm numbness. When you’re sleeping, you’re likely resting in the same position for hours at a time, which can cause pressure to build up on your nerve endings and lead to a tingling feeling of numbness.
When your arms fall asleep at night, it’s generally because you’re applying extra pressure on your limbs by pinning your own arm down with your body or resting your arm underneath your partner’s body weight. This sensation can also affect other parts of your body, like your hands or legs.