Measurement of basal body temperature
First Claim
1. An electrical instrument for basal body temperature measurement comprising a clock, an entry circuit for electrical temperature signals from a temperature sensor, means so controlling the entry circuit by the clock that entry of a temperature signal is permitted only during a predetermined time period of each day, means connected to the entry circuit for reducing each entered temperature signal by an amount proportional to the time elapsed between the beginning of the predetermined time period and the time of entry of the temperature signal, a store connected to the reducing means for accumulating a number of entered daily temperature signals after reduction, means for processing the accumulated signals to establish a mean temperature level, means for comparing subsequent entered temperature signals with the mean temperature level and calculating when a significant rise in temperature of predetermined significance has taken place, and a first indicator means for displaying the fact of occurrence of the significant temperature rise.
1 Assignment
0 Petitions
Accused Products
Abstract
Temperature readings from a thermistor 16 can be recorded in a counter 20 by means of a self-balancing bridge 17 when gate 15 is open for the same four hours of each day. Clock 10 is set to initiate the four hour period at say 06.00 hrs. so that the body temperature measurement is taken after waking but before rising. Measurements for the first three days of the menstrual cycle are rejected (19) and for the next eight days are accummulated in a store 22. These measurements are subject to a diurnal correction 21 to reduce them to the temperature at the beginning of the 4 hour period. The mean of eight readings is determined (23) and subsequent readings compared (24) with the mean. A Cusum statistical test is then applied to determine the beginning of the infertile period signalled by a rise in body temperature and produce a corresponding display 27.
40 Citations
12 Claims
- 1. An electrical instrument for basal body temperature measurement comprising a clock, an entry circuit for electrical temperature signals from a temperature sensor, means so controlling the entry circuit by the clock that entry of a temperature signal is permitted only during a predetermined time period of each day, means connected to the entry circuit for reducing each entered temperature signal by an amount proportional to the time elapsed between the beginning of the predetermined time period and the time of entry of the temperature signal, a store connected to the reducing means for accumulating a number of entered daily temperature signals after reduction, means for processing the accumulated signals to establish a mean temperature level, means for comparing subsequent entered temperature signals with the mean temperature level and calculating when a significant rise in temperature of predetermined significance has taken place, and a first indicator means for displaying the fact of occurrence of the significant temperature rise.
Specification