Tokyo, February 6, 2015 – Rakuten, Inc. and Toshiba Corporation today released the findings of a study and analysis of data derived from the “Basal Body Temperature (BBT) Type Determination” and “Hormone Balance Check-up” features available on the companies’ joint service for women, “Rakuten Kirei-do-Navi,” a basal body temperature tracking service which is synced to a specially designed basal body thermometer.
The BBT Type Determination feature examines a woman’s BBT graph chart based on BBT measurements taken throughout a single menstrual cycle. The shape of the graph corresponds to one of the six BBT types like “Clear two-tier”; “Slow rise”; “Zigzag in high temperature phase”; “Long low-temperature phase”; “Short high-temperature phase” and “Non two-tier.” Furthermore, the “Hormone Balance Check-up” feature analyzes users’ hormone balance based on the BBT Type Determinations made for three successive menstrual cycles. This lets women know their hormonal balance according to a three (3) color system: “Green” indicates a sound hormone balance; “Yellow” indicates an unsteady hormone balance; and “Red” indicates a balance of concern.
During the winter, due to seasonal factors, including the cold, the autonomic nervous system becomes unstable which can lead to the destabilization of the hormonal balance. In this survey, less than 30% of subjects had the ideal “Clear two-tier” type hormone balance, and the majority of people were the “Zigzag in high-temperature phase” type, where the body temperature is unstable and occasionally drops during the high-temperature phase. The results revealed a conspicuous instability in hormonal balance among women in general.