Periods and diabetes: what you need to know

WRITTEN BY: Dr. Apoorva Gomber, MBBS, MD

How it works

Living with diabetes can often result in high blood sugars during different phases of the menstrual cycle. Personally, I face many challenges and exacerbations in my blood sugars weeks before my periods. And I have heard so many young women complain about glycemic difficulties during their cycles especially during the pre-menstrual syndrome (PMS) phase.

A regular menstrual cycle has different cyclical phases usually ranging between 21 to 35 days and often varies. It is best measured by the number of days between your periods. Commonly, most have a regular cycle of 28 days which includes 3-4 days of menstruation (periods). During a month-long cycle, hormonal fluctuations results in ovulation and then menstruation. These hormonal fluctuations can affect other body systems aside from the reproductive system. Those living with diabetes may experience some unique menstrual challenges as a result of these complex hormonal interactions.

Blood sugar levels are often difficult to control at different times of the month. I often get frustrated chasing my blood sugar graphs on a continuous glucose monitor weeks before my periods — sometimes a few days to over a week. Despite taking high doses of insulin, I feel unsuccessful when I can’t achieve the levels I want. This lack of control is a real thing and I’m sure I’m not alone.

All about the hormones

There are a series of hormonal changes during our menstrual cycle and the cyclical surge and downfall of certain hormones determines the process of ovulation. After ovulation, which usually occurs around the 13-15th day of your cycle, there is an increase in the levels of the hormone progesterone . The progesterone levels are naturally higher during the second half of the menstrual cycle and are responsible for relative insulin resistance. This physiologic response is known as luteal phase insulin resistance .

Various studies have explored the link between progesterone and insulin resistance. Changes in estrogen and progesterone levels can induce a temporary phase of insulin resistance that can last for up to a few days before dropping off. Most females complain of increased insulin requirements to combat this resistance and then find themselves running high.

So how do you overcome it? It’s hard – there’s no doubt about it! I also suffer from similar challenges brought on by premenstrual insulin resistance and I am always altering basal requirements on my pump. Some days, the resistance is so stubborn that I have to double my usual dose. First thing’s first: it’s important you discuss this with your gynecologist and get a work-up to check for a condition often seen among people with diabetes called polycystic ovarian syndrome (PCOS) .

Everyone has a different experience during this phase, and some are able to manage their insulin requirements well, but other just can’t. Do not beat yourself up about it! Once the hormone levels fall back into range and that storm subsides, your insulin sensitivity improves. I often try to exercise and do some form of relaxing activity to manage this stressful time.

Irregularity + moodiness

Irregular cycles are another common complaint among those living with diabetes. The reproductive years are the years between your first period, also called menarche, and the onset of menopause, which is the time periods stop. If you are living with Type 1 diabetes you are likely to experience a slightly shorter span of reproductive years compared to people without diabetes. It has been suggested that more than one third of teenage girls with T1D will have irregular menstrual periods.

With better glycemic control and good planning with your doctor, women living with diabetes can have a normal planned pregnancy if they want to.

Coping with mood swings & periods is another necessary part of this whole thing. Different stages of the menstrual cycle may have different effects on your blood glucose levels. Mood swings and the effect can also vary from person to person and from month to month.

PMS makes some people feel moodier than usual and others bloated and achy. For some, it causes intense mood swings that interfere with daily life. While research estimates about 75% of women experience PMS during their reproductive years, only 3 to 8% develop severe depressive symptoms and anxiety.

Blame the serotonin!

Changes in estrogen and progesterone levels also influence serotonin levels. Serotonin is a neurotransmitter that helps regulate your mood, sleep cycle, and appetite. Unfortunately, low levels of serotonin are linked to feelings of sadness and irritability.

So how do you combat this?

  • If you don’t already, start keeping track of your menstrual cycle and your emotions throughout its different stages.
  • Supplementing with Vitamin B-6 might also help with PMS symptoms.
  • Eat foods rich in Vitamin B like fish, chicken and turkey, fruit, and fortified cereals.
  • Several lifestyle factors also seem to play a role in PMS symptoms like regular sleep, exercise and adequate nutrition.
  • If other treatment options aren’t helping, taking an antidepressant especially Selective Serotonin Receptor Inhibitors (SSRI) may help, but talk to your doctor to figure out the best course of action.
  • Hormonal pills are another possible option.

If you take a contraceptive pill, you may experience a different effect on your blood glucose levels than when you weren’t taking the pill. There are various forms of contraceptive pill available and most of them increase your body’s insulin resistance, making it harder to control your blood sugar. In general, it is considered safe to use these methods if you have diabetes, but it’s important to be aware that using a hormonal contraceptive may change your glycemic control. Make sure to pay extra attention to your blood sugar when you are starting or changing your hormonal contraceptive method.

The takeaway

It’s a good idea to start tracking some important things. Here is a list of some essential things to track via apps or a journal :

  • Cycle length
  • Period length and heaviness
  • Fatigue
  • Blood sugar levels
  • Weight
  • Cravings
  • Any other symptoms you might be concerned about

For more detailed discussions regarding managing diabetes and your menstrual cycle, get in touch with your endocrinologist and gynecologist.

1 Like

I am so happy to see more articles like this popping up recently!!! Hormones have a MAJOR impact on blood sugar control for so many women, and yet it’s a topic that is often glossed over as a minor issue.

I have been tracking my cycle with my Fitbit since the feature was launched and this has helped a lot in allowing me to be more aggressive with insulin adjustments. But even its predictions, with all its fancy algorithms and aggregated data, are not pinpoint accurate. It’s still something I haven’t gotten right, and it causes many highs and lows. Ultimately, it definitely has a major impact on long-term diabetes control for myself and many women.


This was not even on my radar when I was younger. Who would have thought hormones and time of the cycle would be so a deal breaker for us women. It wasn’t until blood testing came into my life that I started noticing the brutal lows I was having about 2 weeks before my periods started and the frustrating highs as it started.
Thankfully when I went on a pump, I was able to set different profiles based on the time of the month. My biggest problem was recognizing where I was in my cycle.i was never very regular. Some months 28 days, some months 18 days some months 32 days. It was a mess! So it would take a day worth of lows before things would click.
And on a side note, hormones are challenging on both sexes! The stories of young boys going through puberty and the huge amounts of insulin needed to keep things in line! It is very nice to see people are starting to realize how hard it is for us to manage this disease with some many things in our own body that we can’t control.

Yes, the irregularity is what makes it so hard. I’ve worked out my general pattern, but that’s about the best I can do, the rest is guesswork. Even tracking my cycle with Fitbit for the past year, with all its fancy algorithms and data aggregation and with a fairly regular cycle in terms of length, it can only predict things in the general ballpark. Yesterday I spent 100% of my time in range, which was great, I felt like I was finally right with my settings. Then overnight I dropped low for six hours and today have been having to eat constantly not to go low despite lowering my basal rates by 20% and cutting my ratios in half. Fitbit was predicting this to happen in five days. And, unfortunately, the same thing happens with highs, except I experience highs for several weeks instead of just several days as I do with the lows. I can’t use different basal settings because my insulin needs don’t always change the same amount; although the general pattern is the same, some months my insulin needs increase by only 25% and other months by more than 100%.

I feel one of the biggest challenges with monthly hormones is that they affect you every month, a dozen times a year, for many decades on end. It feels like trying to adjust pump settings on a bed of constantly shifting sand rather than the solid rock others seem to be standing on. And so often, women aren’t even told that this could be an issue. I learned about it from other women with Type 1 rather than nay of my doctors. At least puberty is something that everyone faces (my total daily dose was about 85 units during my puberty years…) and is well acknowledged by doctors, and hopefully something they work with parents to address as was my case. None of the big diabetes books I’ve read have acknowledged cycle hormones with more than a sentence or two, and even my own endocrinologist (who has Type 1 himself and is great) isn’t able to offer me any advice.

1 Like

As a diabetic, it really surprised me that the menstrual cycle has not been investigated in greater detail in its interference with insulin response. As a Sensiplan (symptothermal method) instructor I was not surprised at all. The female cycle is conveniently largely ignored because your cycle may vary and would require a lot of attention in its idiosyncrasies. In fact, it is even the reason why studies and drug trials favour male subjects. There is something a diabetic female can do to gain insight into her cyclical hormone evolution. I don’t recommend Fitbit Period Tracking because it is based on the very unreliable calendar method: a method that assumes each bleeding to be a period and that assumes ovulation by best-guess-algorithm. Ovulation cannot be predicted by dates because it is a sensitive endocrine process easily thrown off by factors outside your control. What matters in charting your cycle is ovulation confirmation which cannot be achieved by tracking bleeding dates. It is at ovulation that your hormones shift, and it is ovulation that makes a subsequent bleeding a period. There are two biomarkers to track to see what is happening in your cycle. Cervical fluid shows you your estrogen activity before ovulation and basal temperature shows you your progesterone activity after ovulation. I published my insulin profiles in relationship to cycle hormone shifts here

Thanks for the information! Very useful and thought-provoking. The Fitbit app does allow tracking of symptoms (including fluid consistency information), so I’m not sure if that’s the sort of thing you’re referring to. I think it also uses heart rate and other data that it tracks automatically to predict periods. Usually it’s pretty accurate for me (+/- a day) but this month was an exception.

Fitbit has added a CF feature but its interpretation is Calendar-Method-based, which works well if your cycle is regular. CF tracking is inconclusive for ovulation confirmation unless it follows a standardized method that correlates it with resting temperature. Unfortunately, CF reading is not intuitive and takes about six cycles under instruction to learn. This is why Fitbit offers a CF category labeled ‘unusual’ as a catch-all when users are unsure. You can even have several waves expressed in fertile category CF and still not ovulate, especially as a diabetic. I apologize to hijack your comment, it just hit a nerve for me because FemTech is such a fast-growing industry and it has created a huge chaos for the individual methods. In Diabetes care, conclusive hormone tracking is necessary because any adjustments in insulin rates and ratios can have such serious consequences. If I took the same basal rate on CD 4 that I take on CD 21 provided ovulation occurred I would certainly have a seizure. So there is little margin for error. Mind you, my own fluctuations may be more pronounced due to my age. Thank you for reading my article!

1 Like

No worries at all on “hijacking”—this is exactly the type of thing I think needs to be discussed more! To be honest, I know nothing about any of what you are saying, so I’d like to read up more and learn. I’ve read about basal body temperature tracking before, and have thought about buying a thermometer, but all the ones I see online have black-on-grey screens, which I don’t think I’d be able to see. So I need to find one with a really high contrast screen (like backlit numbers on a black background). I feel like the chaos created by hormones each month and struggling to make adjustments and stay in range has a hugely negative impact on my diabetes control, so if I could get a clearer handle on when and by how much I need to adjust insulin, that would be a huge help.

1 Like

With vision impairment I would go with a bluetooth basal thermometer. These send your temp readings directly to a compatible app where you can see it on a bigger lit up screen like a tablet. Tempdrop comes to my mind because more and more cycle apps are integrating it

1 Like

Wow, thanks so much! This product looks great! Is this something you’d wear all night, every night? Or just during certain phases?

1 Like

For making insulin dosing decisions you want to have complete charts. This is because even after you have confirmed ovulation which kicks off progesterone secretion, it fluctuates. Wear the temp sensor every night because daily entries of resting temperature and fluid give you insight into your hormone ratios beyond ovulation. Imagine your hormones like an orchestra: different players sound their instruments together but sometimes individual instruments dominate in volume. The same is true for hormones, they interplay, and their interference with insulin depends on whichever has the lead. When progesterone is peaking, causing temporary insulin resistance, it will show in high resting temperatures because this hormone has a warming effect. Daily entries will also allow you to see the let-up of progesterone which may not coincide exactly with menses. It is unmistakable by those high resting temps taking a nosedive. This is a lot of information and it is normal to be overwhelmed. It takes a few charts to see your hormones in action to grasp it. If you ever have a question, message me.


Thanks so much for all this information! I think I’ll buy the temp-drop and see if it helps me fine-tune control around this issue. Do you have a specific app or program that you use for tracking BGs and hormones?

I admit I don’t use TempDrop myself. I chart on sympto Plus (Android) with a cheap Easy@Home basal thermometer. It is backlit as well. sympto guides you in collecting your data and interprets it according to the symptothermal method. (This method has been studied by the Department of Gynaecological Endocrinology at the University of Heidelberg, Germany.) is a small organization with an emphasis on teaching the method, and has not yet integrated Bluetooth capabilities, however, you could manually input your TempDrop readings. TempDrop is a very expensive thermometer. I would recommend learning the method first before buying the sensor. This is at the heart of why fertility-awareness-based methods (FAMB) are failing women, because industry presents technology and software in a misleading way, the reality is that no gadget can substitute for a thorough method training in cycle literacy. It’s a bit like insulin pumps, without training they would not work out for patients. If you decide to try sympto, message me if you like. ETA: NeoFertility app out of Ireland has now integrated TempDrop data transfer and offers symptothermal method. Their interface is busy in my estimation but you could check it out. Definitely get an instructor though.