INSULIN RESPONSES FOLLOWING GLUCOSE-ADMINISTRATION IN MENSTRUATING WOMEN

OBJECTIVE: The aim of the study was to investigate changes in insulin sensitivity during the menstrual cycle, in a group of regularly menstruating black African women. METHOD: Insulin responses to intravenous glucose (300 mg/kg) were assessed, for up to 3 h, in 3 groups of age- and body mass-matched non-obese sedentary Nigerian women: Group A, 7 women in the menstrual follicular phase; Group B, 7 women in the menstrual luteal phase; C, 7 men. RESULT: Women in the menstrual luteal phase had the greatest integrated first-phase insulin response and insulin/glucose ratios, much higher than the similar values for these variables obtained in other groups. This suggests that the menstrual luteal phase is associated with relative insulin resistance. CONCLUSION: Black African women in the menstrual luteal phase demonstrate an exaggerated insulin response to an acute glucose load and are thus relatively insulin-insensitive. This confirms previous observations in Caucasians.