A basal thermometer is used to measure the human base body temperature. It is different from a regular fever thermometer in that it is much more precise. It can be used orally, vaginally, or rectally. Basal thermometers are commonly used to determine when a woman is ovulating. A name-brand basal thermometer will typically cost around $10 US Dollars (USD).
Basal body temperature is a person’s lowest temperature while at rest. The temperature is attained after at least three hours of sleep, although some experts believe that five hours are necessary. A basal thermometer is typically used to take the temperature as soon as a person wakes up, before her feet have even touched the floor. Exercise, hunger, or stress can all change a person’s core temperature, so it is recommended that an alarm be set at the same time every day in order to track temperature.
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There are many different types of thermometers available on the market depending on a person's needs. The peculiarity of a basal thermometer is that it is extremely sensitive and precise. It can detect changes in the human body temperature up to 0.01 degrees Fahrenheit as opposed to regular digital thermometers that can only measure temperatures up to 0.1 degrees Fahrenheit.
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It is more reliable to use a basal thermometer to measure the temperature of the human body inside a cavity. Rectal, vaginal, and oral temperatures are more reliable than temperatures taken under the arm. If the basal temperature is going to be tracked over time for comparison, it is important to measure temperature consistently in the same orifice.
Sometimes a basal thermometer is referred to as an ovulation thermometer because of its role in family planning. Most women's basal body temperature will dip before they ovulate and then rise until menstruation. A woman's temperature during her menstrual cycle can be tracked from month to month, allowing her to detect when she is most fertile. This information is used both as a method of preventing pregnancy and getting pregnant. Basal body temperature tracking is also used to detect thyroid disorders.
Basal thermometers are available in most drug stores. They usually cost between $5 and $15 USD depending on whether the basal thermometer has special options. Some thermometers can record multiple readings. Other thermometers measure temperatures within seconds, while others need nearly a minute to execute an accurate reading.