We will enroll 84 women that being starts a chemotherapy protocol with a Anthracycline and Cyclophosphamide (AC) as a part of breast cancer treatment. All volunteers will be submitted a 30 minutes TENS prior to chemotherapy administration. Three different TENS treatment will be test: 1) placebo; 2) high frequency and 3) low frequency. The self-adhesive electrodes will be positioned in the same position for all different TENS treatment (opposite arm to the chemotherapy infusion). The eletctrodes will be positioned as follows: the first electrode at the PC6 point which is located proximal to the flexion fold of the wrist in the middle of the anterior face of the forearm, between the tendons of the long palmar and radial flexor muscles of the carpus and the second electrode at any point in the hand. After that, all volunteers will receipt a formulary to self-complete a nausea and vomit symptoms record during the next 24 hours. Number of incidence and magnitude of the symptoms will express the accumulated indices the occurrence and severity of the symptoms, as further describe in this protocol.