basal body temperature method of family planning


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basal body temperature method of family planning

a natural method of family planning that relies on identification of the fertile period of the menstrual cycle by noting the rise in basal body temperature that occurs with ovulation. The progesterone-mediated rise is 0.5° to 1° F; rate and pattern vary greatly from woman to woman, and to some extent from cycle to cycle in any one woman. The woman keeps careful records over several cycles, taking her temperature at the same time every morning, before getting out of bed or doing anything else. She may take her temperature orally or rectally in the same way every day. Talking, getting up, smoking a cigarette, eating, or even moving about in bed may change the temperature. Many other factors may also affect the reading, including infection, stress, a bad night's sleep, medication, or environmental temperature. If any of these factors is present, the woman notes them on her record. Abstinence is required to avoid pregnancy from 6 days before the earliest day that ovulation was noted to occur during the preceding 6 months until the third day after the rise in temperature in the current cycle. The days after that period are considered "safe" infertile days. Another way of calculating the possible beginning of the fertile days is to subtract 19 days from the shortest complete menstrual cycle of the preceding 6 months. The basal body temperature method is more effective when used with the ovulation method than is either method used alone. The combination of these methods is called the symptothermal method of family planning. Compare calendar method of family planning, ovulation method of family planning.