It is very common for Carpal Tunnel Syndrome to occur during pregnancy, especially during the third trimester. This occurs because pregnancy often leads to water retention and generalized swelling throughout the body, including the hands and wrists. When the hands and wrists swell, the extra fluid can compress the Median Nerve within the confined space of the Carpal Tunnel. This compression results in nerve dysfunction, causing numbness, burning and pain.
Fortunately, pregnancy-induced Carpal Tunnel Syndrome generally resolves within the first 3 months following delivery as swelling  and water retention gradually subside. Breast-feeding can prolong symptoms. There is a small possibility that the symptoms do not resolve spontaneously and that additional treatment becomes necessary. If symptoms are very bothersome while pregnant, treatment with wrist splints, activity restriction and cortisone injection can provide substantial relief.  Cortisone injection into the carpal tunnel is commonly performed and is considered safe during pregnancy.