Diabetes and Menstruation - Between Insulin Resistance and the Munchies

I was diagnosed with Type 1 diabetes at the age of 10. Back then my parents and I were informed that going through puberty as a person with diabetes might be a challenge. Thankfully my puberty went pretty smoothly without any big diabetes related issues. 

What I was not prepared for was the fact that the menstrual cycle can have a huge impact on diabetes and vice versa. My doctor didn’t discuss this with me nor was it part of educational diabetes lessons. Surprisingly, my gynecologist had a better idea of adjusting my diabetes therapy than my diabetes team back then. 

Even nowadays when I talk to peers about the topic, most of them are not aware of the fact that the monthly cycle, the hormones to be specific, can make your blood glucose values go crazy and make diabetes management extra challenging. And that’s not even the whole story. 

Just a quick reminder before I dive deeper into the topic: the menstrual cycle begins on the first day of menstruation and ends with the following menstruation. This process is repeated every 21-35 days if everything goes smoothly.

Relationship between menstruation and blood sugar fluctuations have been known for a long time

Fact is, the connection between menstruation and blood sugar metabolism has been known for decades. More precisely, since the 1940s, when researcher H.I. Cramer shared his findings on the relationship between the monthly cycle and blood sugar fluctuations in the Canadian Medical Association Journal.

So why is there so little discussion and training on it? Shouldn't we be educated about this as part of standard diabetes education? We all need to learn that the menstrual cycle is routinely considered during therapy adjustments.

Take a moment to think about it. How much support do you get from your team of HCPs when it comes to managing your blood sugars before and during your menstrual cycle? Have any of them asked what phase of your cycle you’re in while talking about insulin adjustments? They probably should.

Consider the following: there are almost 200 million women with diabetes in the world. And people with an uterus have menstruation. Also there are differences in menstrual cycle between women with Type 1 diabetes and women without diabetes. This includes, for example, irregular bleeding, strong period pains, a very heavy and/or longer period, as well as skin problems. 

Hormones are responsible for the blood sugar mess during menstruation

The menstrual cycle consists of two phases, the estrogen phase and the progesterone phase, and both have an impact on insulin sensitivity. Sure, there are a lot of hormones involved, but to be more specific, the sex hormones estrogen and progesterone are the two culprits responsible for the “bloody mess” which occurs monthly.

The concentration of these two hormones is higher than usual a few days before the start of your period (i.e. in the second phase), which can be noticeable as a result of increased blood sugar levels. 

Between insulin resistance and the munchies 

The reduced insulin sensitivity impacts every person’s blood sugar differently. I personally notice higher blood sugar levels or a stronger insulin resistance about 3-5 days before the start of my period. On top of that, food cravings are another challenge that makes it even harder to manage my diabetes during the monthly cycle. 

Progesterone that causes you to be temporarily more resistant to insulin is a sneaky little bastard since it will likely also cause food cravings. And I am not talking about salad. Chocolate, Ice cream...you name it. 

Imagine that. Your blood glucose readings are harder to manage because of a temporary insulin resistance plus you could easily eat everything in sight (and then some!).

How I learned to manage my diabetes during my monthly cycle

As always, knowledge is power! I am trying to document my blood glucose readings as well as possible, especially on those days when my diabetes seems to have a mind of its own. On those days I try to add as much context to my blood glucose readings as possible, e.g. food and feelings. 

One day I discovered some patterns. There was one phase of the month where I needed much more insulin than usual, combined with headaches and crazy tiredness. 

And surprise surprise, these were the days before my period. Now I became curious and also started using a period tracker app to add even more information and match it with my glucose readings. 

This was also  when I started using the mentruational tag in the mySugr app on a regular basis. By adding this additional detail I can explain a lot of my unusual blood sugar fluctuations much better, or I can immediately explain to my endocrinologist how one of the outliers in my blood sugar data came about.                   

Learning from data to adjust therapy

Having gathered all this information, I started working on an action plan. Luckily, the monthly cycle is typically not totally unexpected and with the help of a cycle tracker, it can be predicted pretty accurately. Knowing your cycle is definitely important, because this is the only way to counteract the fluctuations in blood sugar. 

I am managing my diabetes with the help of an insulin pump, so for me the most handy solution was to program a “period basal rate” that I start 5 days before my period and end on the first day of my period. During these 5 days I personally let my basal rate run at 130% - 150%  (please note, these are my personal therapy settings and needs. Adapting insulin may vary from person to person and should be discussed with your diabetes team beforehand).

Also, the extent to which the therapy must be adapted to the cycle is very individual and it takes a little time to work it out optimally. This is precisely why accurate documentation and a well-trained team of doctors are so important and helpful. 

Last but not least, a few (fun) facts about menstruation:

• A woman bleeds a total of 6 years of her life
• There is a Disney film about menstruation
• Menstrual cramps can be as painful as a heart attack
• Menstruation is deemed impure in many religions
• Cold temperatures can negatively affect the strength of flow and length of menstruation
• May 28th is World Menstrual Day
• Contrary to the majority of advertising, menstrual blood is actually red, not blue ;)

With all of this in mind, power to the period!