An Examination of Factors Associated with Biphasic Patterns of Basal Body Temperature in Healthy Female Undergraduates

Abstract

  Basal body temperature was measured, body composition was analyzed, and dietary intake and factors associated with whether or not one had a biphasic basal body temperature were examined in 31 female undergraduates with a menstrual cycle of normal length. Based on measurements of basal body temperature, the 31 subjects were divided into two groups: a group of 7 subjects with a biphasic basal body temperature menstruation and a group of 24 without a biphasic basal body temperature menstruation. The number of years since menarche was compared in the two groups. Results indicated that a higher proportion of women in the group with biphasic basal body temperature menstruation had experienced menarche 8 years prior. Furthermore, when 16 subjects whose menarche had occurred more than 8 years prior were examined, those in the biphasic basal body temperature group had significantly higher intakes of protein, total dietary fiber, six minerals (including calcium and iron), and eight vitamins (such as vitamin K, folic acid, and vitamin C) compared to those in the non-biphasic group. Results indicated that the passage of 8 years since menarche was associated with biphasic basal body temperature. Results also indicated that dietary intake status was related to having a biphasic basal body temperature if 8 years had elapsed passed since menarche.