This is a randomized, placebo-controlled, triple blinded clinical study to evaluate the effects of topical linseed oil on patients with pregnancy-related carpal tunnel syndrome. Sixty hands with pregnancy-related CTS aged between 18-45 with gestational age 20-32 wk, after taking signed informed consent, according to the electrodiagnosis classification criteria with clinical picture correlated with CTS, are included in this trial. The main exclusion criteria included: recurrent carpal tunnel syndrome; Positive history of trauma or fracture of wrist bones, surgical release of median nerve, direct injection into carpal tunnel of wrist; Evidence of cervical radiculopathy in EMG; Systemic disease including neuropathies (rule out by nerve conduction study of ulnar nerves), collagen vascular diseases such as SLE, scleroderma and RA; Endocrine disease such as hypothyroidism, DM, and other disease-inducing neuropathy; Situations such as renal failure, alcoholism or poor medical condition; History of recent and ongoing use of corticosteroids or analgesics that could not be discontinued. 60 hands wih approved cts will allocate to two arms by using blocked randomization.for the patients in the intervention group the linseed oil products with the size of a pea (depending on the size of the patient, so that the area is completely covered) and 3 times a day (morning, afternoon and night), for use in wrist palmar area, without additional massage is prescripted. The control group will receive placebo with the same method for a period of 4 weeks. Boston questionnaire score for CTS and electrodiagnostic criteria, at the beginning time and after 4 weeks of trial, will be evaluated, by a single researcher.