Can We Prevent Gestational Diabetes?
Understanding Gestational Diabetes: controlling the controllable and supporting the uncontrollable
Written by Dr. Fiona Callender, ND and Pelvic Therapist
Pregnancy can be a stress test on our system and normal physiological changes can sometimes unmask underlying challenges. This is sometimes the case in gestational diabetes. Gestational diabetes is a condition that happens when our pancreatic cells (beta cells) can’t secrete enough insulin to compensate for the changes in insulin sensitivity that happens in healthy pregnancies. Though there are ways we can support you with prevention, even folks with the healthiest lifestyles can still be diagnosed with gestational diabetes. To understand why, and what we can do about it, let’s dive into a bit of the science.
Metabolism in a healthy pregnancy:
There are a number of big and important physiological changes that happen in pregnancy to help the body adapt to growing a baby and a whole new organ, the placenta. Changes in how we use and store energy (metabolism) is just one of the many adaptations that occur in pregnancy.
Insulin and insulin sensitivity:
Insulin is a hormone that essentially unlocks the door for our cells to let in sugar (glucose) for energy. Our cells have insulin receptors that bind with insulin - kind of like a key. When we have insulin resistance, those receptors don’t respond as well and our body doesn’t get that sugar into our cells. Our pancreas then starts producing more insulin to compensate. If our body isn’t responding to this insulin, our blood sugar creeps higher - this is when diabetes or pre-diabetes develops.
In early pregnancy, estrogen and progesterone are high and stimulate increased production of pancreatic cells that secrete insulin. This promotes nutrient storage in mom’s tissue and in the form of glycogen in the liver. This is the body getting ready to support later fetal growth. Insulin sensitivity in this time is pretty consistent - or might even increase.
In middle to late pregnancy, insulin sensitivity decreases in a body-wide fashion. Insulin sensitivity decreases by about 50% by the third trimester. This is largely due to hormones produced by the placenta. This is normal and important as this change keeps the pregnant person from getting rid of or storing her sugar so that it can be moved through the placenta to help baby grow. The placenta’s key role is to get nutrients and oxygen to the baby. Normally, insulin secretion increases by 2-3x to compensate and help keep blood sugar stable.
In gestational diabetes, the pacncreas can’t keep up with the added demand and blood sugar rises. This can happen for a couple of reasons:
Insulin resistant gestational diabetes (50-60% of cases) is the case where someone may have had pre-existing insulin resistance (could be genetic, or due to physical inactivity, diet, and/or changes in body composition). Pregnancy related insulin resistance basically uncovers an underlying insulin sensitivity issue.
Insulin deficient gestational diabetes is a little less common (15-30% of cases) and this is an issue at the level of cells of the pancreas and their inability to compensate with enough insulin. This can happen even without the underlying insulin resistance.
It’s also possible that both of these types exist at the same time.
As you can see gestational diabetes is not caused by eating too much sugar; it is a mismatch between the body's insulin demand and its ability to produce enough of that insulin.
Why do we care?
Gestational diabetes can increase our risk of pregnancy complications, make labour and birth more challenging and even have longer term impacts on the baby.
In pregnancy and birth we see and increased risk of:
Pregnancy induced hypertension
Large for gestational age babies
Preterm birth
Longer labour
Cesarean birth
Perineal tearing and assisted delivery (forceps and vacuum)
We also see longer term maternal complications
Increased risk of developing type 2 diabetes: Up to 10x higher risk in the 3-6 years postpartum.
Increased risk of cardiovascular events: Up to 2x higher risk of cardiovascular disease, even if there was no progression to type 2 diabetes.
Increased risk of gestational diabetes in a subsequent pregnancy
It’s so important to continue being screened for diabetes in the years that follow birth if you have been diagnosed with gestational diabetes. You deserve screening between 6 weeks and 6 months postpartum and then on-going testing in the years that follow.
If you are planning another pregnancy, you can also ask for earlier screening (at 12-16 weeks gestation) as we know that previous gestational diabetes is a huge risk factor for having it again in a subsequent pregnancy.
Complications we don’t always talk about?
Those who get a gestational diabetes diagnosis often report experiencing discrimination from healthcare professionals and relatives. They may internalize stigma and hold on to feelings of guilt and shame. This can lead to avoidance of testing in the future and even disordered eating. It’s so important to me that you know that it’s not your fault. There are strategies we can implement to help prevent and decrease our risk, but that’s not always enough. Getting gestational diabetes does not mean that you failed.
What can we do?
Lifestyle changes can help increase the body’s responsiveness to insulin, which can often offset some of the changes we see as pregnancy progresses.
Diet is an important factor, but it’s not just “cutting out sugar”
A low glycemic diet can reduce the need for insulin and improve our ability to manage our blood sugar. Low glycemic foods are those that raise blood sugar slowly and steadily - such as whole grains, non-starchy vegetables, legumes, and fruits. This is in comparison to foods that cause more rapid spikes, like white bread, sweet drinks, and processed snacks. More fibre left in the food (usually less processed) means the food will take longer to let sugar into the blood.
Higher intake of fruits, vegetables, whole grains, and legumes (plant-based diet) has been shown to lower risk. Again, think fibre!
Reducing foods high in animal fat can be helpful.
The Mediterranean diet is generally a good guideline - and one of the most well studied dietary patterns. This is especially true when supplemented with extra virgin olive oil and nuts.
Try to eat three main meals and 2-3 snacks. Spreading your meals throughout the day versus having one-two big meals tends to result in a better blood sugar response.
Physical activity is key
Exercise - in many forms - seems to consistently show reductions in gestational diabetes risk. Starting as early on as you can - ideally in the first trimester! - and aiming for at least 3 sessions per week is a good goal. If you can hit about 150 minutes of moderate intensity activity per week, you are on the right track!
Building more muscle with resistance training is helpful because this muscle mass can be a “sink” for sugar to get it out of the blood stream.
Aerobic exercise helps increase glucose uptake to the muscles independent of insulin during the exercise. Because endurance exercise depletes some of our stores of sugar in the muscles, part of the recovery after exercise involves increasing the uptake back to those muscles. Both of these mechanisms help reduce the risk of gestational diabetes.
A mix of resistance and aerobic exercise is probably ideal!
Supplements
There are some evidence based supplements that may have some benefit. Recommendations around supplementation are usually person-dependent. We want to consider your history and risk factors when determining if a supplement makes sense for you.
Medications
When needed, medications can either help the body use insulin more effectively or provide additional insulin to help meet the increased demand. Medications can be incredibly important for both mom and baby’s health.
Reminders
Pregnancy is a stress test on your blood sugar management. It can unmask a pre-existing vulnerability in the functioning of your insulin-producing cells or highlight insulin sensitivity that may have been entirely symptom free outside of pregnancy. For those with strong genetic predisposition, lifestyle modification may not fully compensate for the demands caused by changes in pregnancy and the hormones from the placenta.
Remember, getting a diagnosis of gestational diabetes isn’t a failure - and it’s not because you ate too much sugar.
If you want to chat about managing your risk factors, you can book an appointment with Dr. Fiona Callender, ND, our Naturopathic Doctor with a focus on Fertility and Perinatal care.