Self-reported changes in capillary glucose and insulin requirements during the menstrual cycle

Perimenstrual changes in glycaemic control and insulin requirements have been reported in Type I diabetes. A population-based sample of 124 women with Type 1 diabetes, aged 18 to 40 years, were questioned regarding perimenstrual changes in their self-monitored capillary blood glucose and insulin regimen. Sixty-one percent of women noted perimenstrual changes in capillary blood glucose. The commonest pattern was a premenstrual rise in glucose. Thirty- six percent of all study participants were making adjustments to their insulin dose in response to these changes in capillary blood glucose. There was no statistical difference in the mean glycated haemoglobin of subjects making perimenstrual adjustments in insulin (79.1 mmol mol^-1 haem) compared to subjects who noted cyclical capillary glucose changes but did not adjust insulin (73.0 mmol mol^-1 haem). Sixty-seven percent of subjects taking the fixed dose oestrogen/progesterone oral contraceptive pill (OCP) noted perimenstrual changes in glucose. In summary, a third of the women surveyed made perimenstrual adjustments to their insulin dose, but there was no evidence to suggest that this behaviour was associated with improved glycaemic control. Use of the fixed dose combined oral contraceptive pill did not eliminate perimenstrual changes in glucose.