I previously wrote about how my insulin needs change during the course of my menstrual cycle. At the time, I didn’t have an insulin pump. I was treating my diabetes with MDI.

With the Medtronic 670G Insulin Pump, this still happens, but the effects are different.

Total Daily Dose of Insulin – 20 units versus 13!!!

I tend to swing between needing 13 units of insulin daily to needing 20. This corresponds with exercise level, number of carbohydrates eaten, and time of the month.

The Medtronic 670G has a summary history that can be viewed, which shows the total daily insulin amount. Above is a picture of one extreme and below is another.

At the End of my Menstrual Cycle

During the week before I get my period, I need more insulin to keep my blood glucose stable. I am using the “auto mode.” The Medtronic 670G Insulin Pump automatically adjusts the basal insulin based on the CGM sensor reading. This is amazing. However, it has some safety parameters built in, and if the amount of needed insulin is greater than usual, after about 4 hours, it will prompt for a blood glucose reading.

This last cycle, the week before my period, it woke me up every night prompting me for my blood glucose. This is after calibrating it before bed. I think this was a result of my increased insulin needs, although it can also apparently be caused from a faulty sensor. In any case, the only “symptom” I had at the end of my menstrual cycle was this annoying event of being woken up in the middle of the night.

Once I got my period, my insulin needs decreased, and the pump stopped waking me up at night…

At the beginning of my Menstrual Cycle

I get low blood glucose :(. The low blood glucose is NOT caused by the auto mode/basal insulin delivery, but rather by me entering the number of carbs I am eating. During the beginning of my cycle, I am MORE sensitive to insulin, the my usual carb/insulin ratio that’s programmed into the pump, is not correct.

I successfully navigated this by entering only about 1/3 of the carbs I ate for breakfast… But for dinner, I didn’t do this, and my glucose nose dived and I had to drink soda to recover…

I hate low blood glucose.

Summary

With the insulin pump, I’m able to achieve better glucose levels throughout my menstrual cycle, but the amount of insulin I need per day increases as I approach my period. The increased need causes the pump to wake me up in the middle of the night.

Then, at the beginning of my cycle, I am much more susceptible to getting a hypoglycemia (low blood glucose) event.

Possible Solutions

In this case, the difference may have been more drastic because I also decreased my exercise level around the end of my menstrual cycle. Maybe if I increase my exercise level, the change in insulin needs won’t be as dramatic, and I’ll be able to sleep undisturbed. Alternatively, I could try not using auto mode, but I really do love how great auto mode is at getting me to near perfect numbers every morning. I’ve had diabetes for years, and waking up with like a 160 mg/dL glucose level was the norm. Now I wake up with a reading close to 120 mg/dL. Amazing.