Insulin resistance in Pregnancy: How to Know You Have It + What to Do About it

Congrats, Mama! As you await holding that beautiful bundle of joy in your arms, you’re no doubt doing all you can to be as healthy as possible for the baby and for yourself. Maybe you had gestational diabetes in a previous pregnancy, were overweight at the time you conceived, or have been diagnosed with prediabetes or Type 2 diabetes. In any of these contexts, you’ve likely heard the term insulin resistance. Here, let’s talk about what insulin resistance is, why it’s actually normal (to a certain extent) during pregnancy, and how to eat healthily (no need to eat for two!) during pregnancy. 

How is insulin supposed to work in your body?

According to the Centers for Disease Control and Prevention (CDC), here’s how blood sugar regulation works normally: “When you eat, food is broken down into sugars that circulate in your blood. This increase in blood sugar causes an internal organ called the pancreas to release insulin. Insulin acts like a key to let blood sugar into your body cells, which use the sugar as energy. After this happens, your blood sugar returns to a normal level.”

So what is insulin resistance?

Insulin resistance occurs over time when some cells in your body have a harder time responding (aka become resistant) to insulin. This is caused by chronic high blood sugar, which occurs especially from “spikes” due to added sugars you eat or drink (think  sweet treats but also sweetened beverages like soft drinks, sports drinks, and the flavor shots added to your drive-through morning cuppa).      

How do you know you have it?

There is no specific blood test for insulin resistance [2]. If your doctor or healthcare practitioner suspects you have insulin resistance, they may check an oral glucose tolerance test (also known as a GTT, and this is a regular part of pregnancy bloodwork, done between 24 and 28 weeks gestation, to screen for gestational diabetes), a Hemoglobin A1C, and a fasting plasma glucose (normal values for each test are explained here). Increasingly, some healthcare practitioners are ordering a test called the Kraft Test,  also called an “oral glucose tolerance test with insulin assay.” A Kraft Test lasts longer than a GTT and measures insulin levels in addition to blood glucose levels. 

Signs and symptoms of insulin resistance include dizziness, headaches, low energy, trouble sleeping, carb cravings, mid-afternoon “slump” or fatigue after eating.  

Can insulin resistance be normal during pregnancy?

To a slight extent, insulin resistance can be a normal part of pregnancy, especially the further a woman progresses [3]. This is one of many adaptive mechanisms her body has to ensure that her baby gets the nutrients he or she needs no matter what. However, in women who already had insulin resistance before they got pregnant, the additional insulin resistance associated with pregnancy can lead to gestational diabetes along with increased rates of preterm labor, preeclampsia, postpartum hemorrhage, and other problems. 

Registered dietitian and diabetes educator Lily Nichols, author of the excellent pregnancy nutrition guide books Real Food for Pregnancy and Real Food for Gestational Diabetes, notes that the conventional definition of gestational diabetes is ‘a type of diabetes that develops during pregnancy.’ But Nichols considers gestational diabetes ‘a type of diabetes that is first diagnosed during pregnancy.’ 

Shockingly, she notes that within 5 years of giving birth, 70% of women who experienced gestational diabetes will go on to receive a type 2 diabetes diagnosis (Nichols, 3). From this statistic, we know that identifying and addressing insulin resistance is crucial for ensuring both mothers’ and babies’ health. 

How can you minimize insulin resistance during pregnancy?

Fortunately, insulin resistance can be improved (another way of saying this is that you can increase your body’s sensitivity to insulin). Exercise, especially walking for 10 minutes or so after meals, helps decrease insulin resistance. Check with your healthcare practitioner about whether a continuous glucose monitor (now available over-the-counter and potentially HSA-eligible, according to this GoodRx article) is right for you. 

The biggest bang for your buck unsurprisingly comes from improving your nutrition, both what you eat and how you eat it. As one example, you’ll have a smaller blood sugar spike from sweet treats consumed after a meal that includes healthy fats and protein as compared to eating, say, ice cream in the middle of the afternoon. Nichols’ books Real Food for Pregnancy and Real Food for Gestational Diabetes are veritable gold mines of information about eating to improve insulin sensitivity. Nichols’ recommendations (which differ in important ways from conventional guidelines!) have even helped women manage gestational diabetes without taking insulin. 

Written By: Anne Marie Williams

References:

[1] DiNicolantonio JJ, Berger A. Added sugars drive nutrient and energy deficit in obesity: a new paradigm. Open Heart. 2016 Aug 2;3(2):e000469. doi: 10.1136/openhrt-2016-000469. PMID: 27547437; PMCID: PMC4975866.

[2] Freeman AM, Acevedo LA, Pennings N. Insulin Resistance. 2023 Aug 17. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan–. PMID: 29939616.

[3] Sonagra AD, Biradar SM, K D, Murthy D S J. Normal pregnancy- a state of insulin resistance. J Clin Diagn Res. 2014 Nov;8(11):CC01-3. doi: 10.7860/JCDR/2014/10068.5081. Epub 2014 Nov 20. PMID: 25584208; PMCID: PMC4290225.