Does you basal need to change throughout the month?

Do you find your basal changing throughout the month? I’m trying to get a sense whether this differs between males and females.

I’m getting a bit frustrated with basal testing. I’ve been trying this for months and thought I nailed the dosage when a straight line appears for that duration for a few consecutive days. And then all of a sudden, the line is up and down again and I’m back to square one.

I’m a female and I read hormones and the menstrual cycle has something to do with this. Where on different times of the month will see a need in increase insulin. And if you look at the day ranges in the below link, it changes every few days😭

Just using my overnight BG as a reference (this is the best because there is no food or bolus), i haven’t been able to consistently achieve a straight line consecutively for an entire week. 3-4 days is max and then my line becomes non linear. I don’t know whether this means my basal dosage is wrong or related to hormones. And I find myself constantly tweaking my insulin dosage only to repeat this all over again a few days later when i go low overnight due to the increase of insulin (which I needed for those previous few days but not any more).

I get the impression from some of the threads I have seen that once you get your basal right, it doesn’t change very often. Why is it not the case for me, …is it hormones? For the ladies here (not in menopause), are you able to maintain the same straight line for the entire month?

It was a roller coaster when I was perimenopausal. I used to use two basal programs. A temporary basal rate works well too but I didn’t like having to set it every day. I never went back and forth. I needed more leading up to the start of a period and then it dropped like a rock as soon as a period started. I didn’t have CGM at the time so it was even more difficult.


Yes, basal rates change constantly. Every few days it needs to be raised or lowered. Sometimes every day.

I find using temporary basal rates very useful. I get my basal rate into “sort of” the right range and then use temporary basal rates (usually a new one every 12 hours) during fluctuating periods. It’s exhausting. I’m hoping a closed-loop system like the t:slim will allow me some relief from constant tweaking.

I am jealous of people who can set a basal rate and only change it a few times a year or tweak it here and there. That has just never been my expereince of diabetes as a woman.

I’ve given up on basal testing because within a week it will be out of date again. (But it is useful for determining general basal pattern, although even that changes, as I find dawn phenomenon comes and goes throughout the month…)


Its good to know that I’m not alone with these fluctuations, it is exhausting.

Are we the minority? Is it more common to find people have steady basal rates - does this really exist (particularly for women)?

My insulin needs change on a weekly basis if not more frequently. I have about 2 consecutive days per month where all the stars align and I basically don’t need to worry about my BG’s. Unfortunately they aren’t the same 2 days every time but it can vary from just before my period to just after :woman_shrugging:.

I also have about 2 days a month where no amount of insulin will bring my BG down where I want it to be until all of the insulin I’ve infused or injected hits at once and then I get low enough that I want to eat the kitchen. I do have different basal profiles but I find that by the time I realize I need more or less basal that the insulin resistance/sensitivity has already passed.

Something that I have been trying lately that seems to work is assuming that I am always insulin resistant so I round up my carb count but I don’t just deliver the bolus all at once. I give 70% upfront and set an extended bolus for the remaining 30% over 1 hour. If I start to go low before the bolus finishes I can cancel the remaining bolus and mitigate the low. It reduces the spike I usually see from food and gives me some peace of mind that even if I start spiking that very soon I will get an extra boost of insulin to control the spike.


It absolutely, 100% exists for women. It’s mentioned everywhere in books and articles about things that affect blood sugar, but usually limited to a sentence or two with no specifics. It’s just that, for whatever reason, it’s not often talked about in detail as far as management strategies go. So, while there are entire forum threads and books about how to manage every other aspect of diabetes control, this issue is pretty much left up to each women to figure out themselves. And many (myself included) aren’t even aware that it’s a factor until we learn about it from other women with diabetes.

I used to feel like I was missing something obvious or doing something wrong for years, and it was very frustrating. Then I went on a trial CGM (the kind where you can’t see the results until they’re downloaded) and saw that my control went from 95% in range one day to 23% in range the test, with no changes to food or activity on my part. It’s taken me years to figure out strategies that (mostly) work, but as you said, it’s utterly exhausting to be doing constantly. And often I still have highs and lows at various times each month despite my best efforts, as the timing and amount of change is never the same cycle to cycle.


I’ve also been leveraging the extended bolus functionality more recently for the same reasons. The only thing is the basal iq keeps cancelling it every meal time without fail (because I pre bolus) so I have to remember to turn it off.

I do have a few days a month where the stars align :joy: but I can’t predict those days accurately- I know it falls between the middle of my period to about day 18 of my cycle but I can’t pinpoint the exact day as it changes. And there are also days where my BG is stubborn as hell and those too are not predictable. I don’t immediately blame it on hormones, I do a triage first. If my BG is high, there can be a number of things like did I just change my infusion set, is my insulin bad, is my infusion site bad, is my infusion site towards end of life, only when I rule all these out the I start thinking hormones, but by the time, my body changes again and my insulin needs also change :sob:. And it all starts again.

For months I’ve always felt on the back of my mind I keep getting my basal tests wrong. I’ve been literally doing it for months and haven’t been happy with the results. It has only been recently that I realised it’s not the testing that is wrong but my body changing and I’m constantly trying to catch up.

In my experience Control IQ doesn’t cancel a bolus if you are low or predicted to be low. You should be able to upgrade to Control IQ pretty soon I would think so it should resolve that issue at least.

1 Like

:crossed_fingers: can’t wait till we get control IQ. Hopefully it can stabilise the fluctuating insulin requirements without me having to adjust for it.

If you see a straight line for a couple days, you got it. It will bump around, but if you get that flatline behavior at all, you found the basal sweet spot. Your good. Your basal’s are correct.

1 Like

But the following days are so drastically different, have ups and downs all through the night. Like many camel humps.

This week has been rather annoying. On Thu night, my sugar went low overnight so I adjusted it by reducing the strength ever so slightly the next day. That night my sugar rose close to 150mg all night - i don’t believe such a small increment would have had such a big effect. The next day I adjusted it again by strengthening the basal even more, but that night my sugars went even higher. Bear in mind, this dose would have sent me crashing into hypo state two nights ago.

Nothing seems to be working and I feel like blindly trying to adjust my overnight insulin sensitivity without knowing which way it will head. I seem to be alternating between too high or too low every couple of days. How is this possible??

I almost never change my basal insulin. Maybe 2 times a year. I guess this is one good thing about being 70.

1 Like

Absolutely! I have several basal profiles, and despite my best efforts, it sometimes take 1-2 days to figure out it needs to be change.

Also an unexplained low can mean that my period is starting in about 8 hours. Of course not everytime… it is maddening.

1 Like

This sounds exactly like me! The only pattern I know for sure is that about a week before my period for about 3 days I cannot control my levels–I end up taking a lot more insulin, but still stay high, and to boot my depression is so bad it interferes with my life at times during this timeframe. I found things were a bit better on birth control, but I am still hoping I can have a baby someday, so wanted to stop that. I basically set an approximate, and then go from my CGM all day long, constant tweaking and constant monitoring.


I was going nuts once I went on a pump trying to figure out basal rates. It took a long while for me to realize the nasty lows were happening a week before my period started. I never had a regular cycle, so I never knew when it was happening. So I learned that when the lows started up, I knew my period was right around the corner. And once it started, the blood sugars went up. So I had 2 profiles for the week before and the week of. I only had to remember and realize what was happening to make the changes.
And than of course hormone levels month to month are not always the same which also makes this very challenging.
I would imagine the newer pumps that make adjustments could help a lot with this problem. I am beyond this problem now but I am guessing it could be very helpful.


Yes! It’s great to read this thread, so that I know that it’s not just me. :slight_smile: I have been struggling with this a lot recently. I can take the same amount of insulin for the same food and exercise at the same time of day. One day that will make me go low, on another it will not be enough and I will go high, and on another it will be perfect. It truly is frustrating.

I am starting on a control-iq tandem pump this Thursday, and I am hopeful that this will help to some degree. I have been doing all of this manually.


Same!! This is why I get so annoyed with carb counting too, because I’ll eat 15g of carb of one thing vs 15g carbs of another and need totally different amounts. Even with such consistent routine working from home now, I experience different results day to day, albeit less so–very frustrating.

I want to get the Control IQ Tandem, but I am stuck in my omnipod for the next few years. I wish I hadn’t signed back up, because I would like to see if the loop would help me, and I feel like with different canula set options (angles, material) I may get more landscape (my pod only seems to work consistently on my stomach).


That’s weird, I read that before your period the BG goes high but once period starts it goes low. This is my pattern also. You seem to be the other way around :sweat_smile: