Basal and BG Leveling Point During Female Hormone Changes

I’ve written about it before, but it’s so interesting (and frustrating) to observe how effective/ineffective my basal settings are under varying hormone conditions.

As a reminder, I only ever basal test during cycle days 7-12 to get the most consistent hormone conditions for setting my basal profile. I then scale my basal profile up or down via percentage on different cycle days based on my evident insulin resistance or sensitivity.

This cycle…during peak PMS…without any extra percentage of basal running, my bg leveling point was showing up around 230. After The Drop occurred, my same bg leveling point with the same basal profile was 59.

This. Is. What. I. Deal. With. About. Every. Three. Days.

My hormones constantly fluctuate and it’s always a guessing game for how much basal to run. The same profile gives me +/- 170 bg points. It makes eating difficult. It makes unpredictable life with kids difficult. But I persist with it the best I can.

I cannot even imagine how much less work my bg management on a daily basis would be if I didn’t have fluctuating female hormones.

P.S. The Drop occurred in my sleep three days earlier than I expected. Wahoo! :slight_smile:


Help me out with some understanding, Alli.

Is the BG rise from resistance or is it from glycogenolysis, the release of glucose? I assume it is mostly resistance.

(I really don’t know because my personal ovary experience is limited.)


I wouldn’t even quantify it as a rise. It’s just stuck there. For weeks. Fluctuations sometimes higher and sometimes a bit lower. But it just sticks.

But I assume it’s from hormone driven insulin resistance.

A Hormone 230 is so hard to correct. I tinker with adding even more basal (which is already set to the “correct” amount of extra for the cycle day usually). Take a correction. Give it time. Take a correction. Give it time. Take a correction. Tinker with basal. And then at some point it either completely tanks or it just doesn’t move. And I go all day taking walks, drinking water, waiting to eat, the time to eat never arrives, I go low carb and spike. Etc.

A Food 230 is super easy to correct, relatively speaking. If I have a Food 230 during low hormone insulin resistance, it’s no big deal to correct.


Ovarian steroid hormones and insulin resistance are absolutely related. For example, progesterone causing IR is why you see such extreme IR in pregnancy, but non-pregnant women have spikes of progesterone following ovulation every cycle. Estrogen seems like it may improve insulin sensitivity, and estrogen has an extreme spike at ovulation, so you’re having major shifts in that as well. Not to mention that people may have variability in these responses to hormones, and that insulin resistance also can affect ovarian hormones (why one of the treatments for PCOS is metformin, and why metformin may facilitate fertility for some).

I would be more surprised if a naturally cycling diabetic woman says she does not experience changes in IR over her cycle than if she does, and I would expect that to be more likely to reflect a lack of tight control/monitoring than a true lack of changes for most.


Truer words have never been spoken. Thankfully my son is done with much of the really big growth hormone dumps, but man, you could always tell when he was growing because invariably three pump corrections that did nothing would be followed by a syringe delivered rage bolus…I have a lot of sympathy for you since of course yours isn’t going away so fast. Sorry.


I always want to understand the “why”. Everything the body does has a reason. Insulin resistance is because your body wants more glucose available in the blood.

These things makes sense to me in the context of things like the stress hormone cortisol. It wants fuel ready for the fight.

Why do some people have a BG spike after they wake up? Because the body is giving it fuel to get started with their day after they wake up.

All of that makes sense to me.

But what is the reason for the body wanting more glucose a week following ovulation? What is the “why” for that?

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Good questions! …that I’m aware of Zero Answers for. Of all of the T1D books I’ve read, nothing touches on this in any meaningful or practically useful way.

I am on a constant rollercoaster of increasing, decreasing, then increasing, then plummeting insulin resistance each cycle.

I get very resistant to insulin prior to and during ovulation. (I cramp on the ovulating side so I know when it’s happening. Yay for TMI! And those cramps SUCK as I get older. Worse than menstrual cramps for me.) Then I’m resistant post-ovulation…but not as badly as during ovulation…then I get Way Way Way more resistant leading up to cycle restart. And now I have the joy of the plummet happening very unpredictably by +/- 5 days in relation to restart.


It’s probably due to progesterone’s role in pregnancy–it’s the hormone involved in growing/maintaining the uterine lining, so while it increases after ovulation and then decreases if no implantation occurs, its bigger role is in pregnancy where its levels continue to rise. My guess would be that in a non-diabetic (including women who don’t tip into gestational diabetes), there is a benefit to increased IR during pregnancy, as long as it doesn’t get to the point where the pancreas can’t keep up.


I can understand the part about during ovulation. Your body needs fuel for all the …um…you know… the stuff it needs the fuel for.

But a week after. :thinking: Maybe something about the implantation, the body needs glucose for that?

Oh, wow. @cardamom gave an answer right as I was posting my question. Thanks @cardamom!


Also not all women necessarily respond to similar hormone levels the same way. I know for example, progesterone metabolizes into allopregnanolone, which acts on GABA receptors in the brain and typically produces calming effects; however, a small subset of women appear to respond differently in the brain and have paradoxical increases in irritability instead. Wouldn’t be surprising if you see individual differences in responses to hormones that affect insulin resistance and glycemic control as well.


And can say for sure that in 1980s there were endos that denied there was any connection.


@T1Allison I don’t have any good answers for you, but am here to co-sign your statement! I’m actually in the midst of peri-menopause so nothing is making sense, although I can see hormonal changes reflected in my CGM (and just do my best to respond to them). I am MDI Humalog / Lantus. It’s crazy making and I feel like I’m chasing after a boulder that’s rolling down a hill. So sorry that you’re dealing with it. I have researched for years, too, and found nothing that’s practically helpful. Jessica