A woman’s monthly hormone cycle can change the amount of insulin she needs. Don’t be surprised — or caught without as much medicine as your body requires.
Many women find they need more insulin in the days just before they start to menstruate, and that their insulin needs go back to normal when their periods begin. This ebb and flow is completely normal. Estrogen levels rise just before a woman’s period begins, and estrogen increases insulin needs. That doesn’t mean you can simply boost your dose a set amount. Everyone is different. Your menstrual cycle might have a tremendous effect on your glucose levels or it might have none at all. The fluctuation tends to be most dramatic in young women, for example.
Women should be encouraged to use available self-monitoring technology to identify possible cyclical variations in blood glucose that might require clinician review and insulin dosage adjustments. The menstrual cycle can be challenging for most women, but particularly to women with diabetes, and this is because the hormonal fluctuations that occur during the menstrual cycle do affect blood sugar levels.
What is typically see in clinical practice is that the week before a woman starts to menstruate, these hormonal changes increase what we call ‘insulin resistance,’ and so, the insulin that either the woman makes or that she takes by injection doesn’t work quite as well. Then, when menstruation begins, the blood sugar levels tend to drop a little bit.
So, there are a variety of strategies that women can use to improve blood glucose control during the pre-menstrual period. If a woman is not taking insulin, she could try a greater emphasis on diet to control blood glucose levels or even more exercise, which also can relieve some other pre-menstrual symptoms. If a woman is on insulin, she can take a little bit more of the basal, or background insulin during that pre-menstrual week, to help control blood glucose levels. And, of course, if a woman wants to change her therapy, she should consult her primary care provider or her diabetes care provider and present the pattern of symptoms and of blood sugar levels that she’s experiencing that are related to her menstrual cycle.