The detection of fertile and ovulation periods may be performed by women’s body temperature variations. These variations are more accurate if a core-body temperature for their detection is used. Previous medical studies concluded that the use of skin temperature could be influenced by environmental conditions. Since the increasing of the body temperature in this period is only about 0.5 ºC, it is crucial that measurements should be the most accurate as possible. Due to the lack of solutions to realize that in order to measure and analyze the core-body temperature, this paper presents a system to capture, display, and monitoring core-body temperature. It is considered a hardware solution (sensor) to be placed inside cervix and a computer application to communicate and gather the collected data by the sensor. Bluetooth is used to perform the communication between a computer and the sensor. The system evaluation is performed by a medical team in several volunteer women. Furthermore, the collected data by the sensor may be used to study the relation between temperature variations and women health conditions.