Chasing Glucose Levels During Pregnancy: CGM Can Help

Shana Spindler PhD
Shana Spindler PhD
October 20, 2021

Grace Brannon, Ph.D., a professor in health communication at University of Texas at Arlington, received her type 1 diabetes diagnosis at 18 years old—later than the more-common childhood diagnosis. Ten years later, she has three children (a set of twins and a newborn), a penchant for martial arts and long-distance racing, and a decade of experience learning about blood sugar management, including during pregnancy.

“In pregnancy, your body changes so much. For me, my pregnancy with my twins was different than the single baby,” Brannon said, referring to differences she observed on her continuous glucose monitor (CGM). “It was a constant adjustment to regulate my blood sugar.”

Brannon’s struggles with diabetes began before her pregnancies when she was diagnosed as an undergraduate in college. One day in class, her glucometer began beeping. Her professor was convinced that Brannon was using her cell phone and asked her to leave. With little diabetes experience, Brannon didn’t have the language to communicate her health needs and concerns with those around her. Before she could exit the classroom, she passed out from a glucose level of 500 mg/dL (27.8 mmol/L) (it should have been less than 140 mg/dL (7.8 mmol/L)). Emergency personnel took her by ambulance to the hospital.

“It was so embarrassing. My whole world had just changed like a week or two before that,” Brannon said. “I didn’t know how to talk or advocate for myself. That event is why I wanted to go into health communication.” Brannon is now an advocate for talking about the challenges of diabetes and reducing the stigma around it.

The main challenge of diabetes is glucose regulation, which is critical during pregnancy. Mothers who have type 1, type 2, or gestational diabetes are at high risk for abnormal blood sugar levels, which can lead to excessively large babies, increased risk for preterm birth, and serious complications for the infant. According to a recent study in Brazil, researchers observed high blood sugar levels in obese women without diabetes as well. With rates of obesity and diabetes climbing, effective ways to monitor and adjust blood sugar levels in pregnant women are essential.

Check out this Sync article on Gestational Diabetes: A Common but Preventable Pregnancy Complication

In 2017, an international team of scientists and physicians published their findings from the CONCEPTT trial, which examined the benefits of continuous glucose monitoring (CGM) in pregnant women with type 1 diabetes. The results were clear. By the third trimester, CGM use during pregnancy increased the amount of time women were in their target blood sugar range, decreased blood sugar variability, and improved baby outcomes.

Just three years later, in December 2020, after an extensive evidence-based review, the United Kingdom National Institute for Health and Clinical Excellence (NICE) updated guidelines to indicate that healthcare providers should offer CGM to all pregnant women with type 1 diabetes to help them stay within their target blood sugar range and to improve baby outcomes. In addition, the guidelines recommend that providers consider CGM for pregnant women without type 1 diabetes who use insulin therapy if they have problematic hypoglycemia or unstable glucose levels even after attempts to control their blood sugar.

Benefits of CGM During Pregnancy

For Brannon, CGM during pregnancy improved her quality of life. “It’s a mental and emotional toll to know how you’re affecting your baby,” Brannon shared. “But you can use CGM data to make changes that will have better health outcomes for you and the baby.”

In a 2021 review of CGM use during pregnancy, the authors examined randomized, controlled trials alongside real-world data to assess the outcomes of CGM use. They reported that CGM use in women with type 1 diabetes led to increased time in range for blood sugar targets, decreased time above range, and a reduction in preeclampsia. The authors also reported significant improvements in three important outcomes for the baby: fewer large-for-gestational age infants, decreased hypoglycemic events in babies, and reduced neonatal intensive care admissions.  

According to the authors, the published evidence supports the use of CGM during pregnancy for women with type 1 diabetes, but more research is needed for women with either type 2 or gestational diabetes. “Given the global increase in type 2 diabetes pregnancy and widespread availability of more affordable user-friendly CGM devices, data regarding the pregnancy outcomes and costs and benefits of CGM use in this marginalized patient population are urgently needed,” the authors wrote. They also argue for more data collection on CGM use in women with gestational diabetes.

For some women, blood sugar regulation is further complicated by the number of babies they carry. A 2016 study found that an abnormal glucose tolerance test is more likely in women carrying twins or triplets than in women with a single baby.

Brannon is familiar with the constant blood sugar changes while pregnant and the need to closely monitor the trends—for every pregnancy. “Normally, when I have low blood sugar, eating one pack of fruit snack gummies will increase my glucose in 15 minutes, but when I was pregnant it would take longer,” Brannon said. “When you don’t know how long it’s going to take, you eat a second or third pack, and then you end up with high blood sugar and chasing your glucose levels. That was surprising. I didn’t have that with the twin pregnancy as much as the single baby.”

Ways to Level Out Blood Sugar During Pregnancy

Every woman is unique, and how the body responds to pregnancy will depend on a complex combination of genetics, environment, and patterns of behavior. While pregnant women can’t change their genetics—at least not yet—lifestyle factors such as diet and exercise routines are important to consider.

According to the Cleveland Clinic, a nonprofit American medical center, pregnant women can cut the risk of high blood sugar with two simple practices: “watch what you eat” and “step up the exercise.” In general, cut out added sugar and refined carbohydrates, such as white breads, pastas, and rice. Instead, incorporate more fiber from vegetables, whole grains, and fruits. Eating carbohydrates in combination with healthy fats will also help mitigate spikes in blood sugar. Ideally, stick with nutrient dense foods that are minimally processed. As for exercise, the Cleveland Clinic recommends speaking with a physician to determine the best activities for you, but they write that walking, swimming, and yoga are good, low-impact exercises.  

Brannon, a dedicated athlete who participates in martial arts and triathlons, trained throughout pregnancy. She was on the bike until 35 weeks of pregnancy, ran into her third trimester, and swam up to a mile until four days before delivery. While many pregnant women are concerned about spikes in blood sugar and decreased insulin sensitivity, Brannon was worried about steep drops in glucose following exercise. “CGM has been so instrumental in helping my blood sugar not bottom out,” Brannon said. Thanks to careful glucose monitoring, ten years after her type 1 diabetes diagnosis and three babies later, Brannon hasn’t bottomed out—instead, she’s at the top of her game.

References

Gestational Diabetes and Pregnancy

Continuous glucose monitoring in obese pregnant women with no hyperglycemia on glucose tolerance test

Continuous glucose monitoring in pregnant women with type 1 diabetes (CONCEPTT): a multicentre international randomised controlled trial

Diabetes in pregnancy: management from preconception to the postnatal period

Benefits of Real-Time Continuous Glucose Monitoring in Pregnancy

Glucose tolerance in singleton, twin and triplet pregnancies

Tests & Diagnosis for Gestational Diabetes

How to Cut Risk of High Blood Sugar When You’re Pregnant

Grace Brannon, Ph.D., a professor in health communication at University of Texas at Arlington, received her type 1 diabetes diagnosis at 18 years old—later than the more-common childhood diagnosis. Ten years later, she has three children (a set of twins and a newborn), a penchant for martial arts and long-distance racing, and a decade of experience learning about blood sugar management, including during pregnancy.

“In pregnancy, your body changes so much. For me, my pregnancy with my twins was different than the single baby,” Brannon said, referring to differences she observed on her continuous glucose monitor (CGM). “It was a constant adjustment to regulate my blood sugar.”

Brannon’s struggles with diabetes began before her pregnancies when she was diagnosed as an undergraduate in college. One day in class, her glucometer began beeping. Her professor was convinced that Brannon was using her cell phone and asked her to leave. With little diabetes experience, Brannon didn’t have the language to communicate her health needs and concerns with those around her. Before she could exit the classroom, she passed out from a glucose level of 500 mg/dL (27.8 mmol/L) (it should have been less than 140 mg/dL (7.8 mmol/L)). Emergency personnel took her by ambulance to the hospital.

“It was so embarrassing. My whole world had just changed like a week or two before that,” Brannon said. “I didn’t know how to talk or advocate for myself. That event is why I wanted to go into health communication.” Brannon is now an advocate for talking about the challenges of diabetes and reducing the stigma around it.

The main challenge of diabetes is glucose regulation, which is critical during pregnancy. Mothers who have type 1, type 2, or gestational diabetes are at high risk for abnormal blood sugar levels, which can lead to excessively large babies, increased risk for preterm birth, and serious complications for the infant. According to a recent study in Brazil, researchers observed high blood sugar levels in obese women without diabetes as well. With rates of obesity and diabetes climbing, effective ways to monitor and adjust blood sugar levels in pregnant women are essential.

Check out this Sync article on Gestational Diabetes: A Common but Preventable Pregnancy Complication

In 2017, an international team of scientists and physicians published their findings from the CONCEPTT trial, which examined the benefits of continuous glucose monitoring (CGM) in pregnant women with type 1 diabetes. The results were clear. By the third trimester, CGM use during pregnancy increased the amount of time women were in their target blood sugar range, decreased blood sugar variability, and improved baby outcomes.

Just three years later, in December 2020, after an extensive evidence-based review, the United Kingdom National Institute for Health and Clinical Excellence (NICE) updated guidelines to indicate that healthcare providers should offer CGM to all pregnant women with type 1 diabetes to help them stay within their target blood sugar range and to improve baby outcomes. In addition, the guidelines recommend that providers consider CGM for pregnant women without type 1 diabetes who use insulin therapy if they have problematic hypoglycemia or unstable glucose levels even after attempts to control their blood sugar.

Benefits of CGM During Pregnancy

For Brannon, CGM during pregnancy improved her quality of life. “It’s a mental and emotional toll to know how you’re affecting your baby,” Brannon shared. “But you can use CGM data to make changes that will have better health outcomes for you and the baby.”

In a 2021 review of CGM use during pregnancy, the authors examined randomized, controlled trials alongside real-world data to assess the outcomes of CGM use. They reported that CGM use in women with type 1 diabetes led to increased time in range for blood sugar targets, decreased time above range, and a reduction in preeclampsia. The authors also reported significant improvements in three important outcomes for the baby: fewer large-for-gestational age infants, decreased hypoglycemic events in babies, and reduced neonatal intensive care admissions.  

According to the authors, the published evidence supports the use of CGM during pregnancy for women with type 1 diabetes, but more research is needed for women with either type 2 or gestational diabetes. “Given the global increase in type 2 diabetes pregnancy and widespread availability of more affordable user-friendly CGM devices, data regarding the pregnancy outcomes and costs and benefits of CGM use in this marginalized patient population are urgently needed,” the authors wrote. They also argue for more data collection on CGM use in women with gestational diabetes.

For some women, blood sugar regulation is further complicated by the number of babies they carry. A 2016 study found that an abnormal glucose tolerance test is more likely in women carrying twins or triplets than in women with a single baby.

Brannon is familiar with the constant blood sugar changes while pregnant and the need to closely monitor the trends—for every pregnancy. “Normally, when I have low blood sugar, eating one pack of fruit snack gummies will increase my glucose in 15 minutes, but when I was pregnant it would take longer,” Brannon said. “When you don’t know how long it’s going to take, you eat a second or third pack, and then you end up with high blood sugar and chasing your glucose levels. That was surprising. I didn’t have that with the twin pregnancy as much as the single baby.”

Ways to Level Out Blood Sugar During Pregnancy

Every woman is unique, and how the body responds to pregnancy will depend on a complex combination of genetics, environment, and patterns of behavior. While pregnant women can’t change their genetics—at least not yet—lifestyle factors such as diet and exercise routines are important to consider.

According to the Cleveland Clinic, a nonprofit American medical center, pregnant women can cut the risk of high blood sugar with two simple practices: “watch what you eat” and “step up the exercise.” In general, cut out added sugar and refined carbohydrates, such as white breads, pastas, and rice. Instead, incorporate more fiber from vegetables, whole grains, and fruits. Eating carbohydrates in combination with healthy fats will also help mitigate spikes in blood sugar. Ideally, stick with nutrient dense foods that are minimally processed. As for exercise, the Cleveland Clinic recommends speaking with a physician to determine the best activities for you, but they write that walking, swimming, and yoga are good, low-impact exercises.  

Brannon, a dedicated athlete who participates in martial arts and triathlons, trained throughout pregnancy. She was on the bike until 35 weeks of pregnancy, ran into her third trimester, and swam up to a mile until four days before delivery. While many pregnant women are concerned about spikes in blood sugar and decreased insulin sensitivity, Brannon was worried about steep drops in glucose following exercise. “CGM has been so instrumental in helping my blood sugar not bottom out,” Brannon said. Thanks to careful glucose monitoring, ten years after her type 1 diabetes diagnosis and three babies later, Brannon hasn’t bottomed out—instead, she’s at the top of her game.

References

Gestational Diabetes and Pregnancy

Continuous glucose monitoring in obese pregnant women with no hyperglycemia on glucose tolerance test

Continuous glucose monitoring in pregnant women with type 1 diabetes (CONCEPTT): a multicentre international randomised controlled trial

Diabetes in pregnancy: management from preconception to the postnatal period

Benefits of Real-Time Continuous Glucose Monitoring in Pregnancy

Glucose tolerance in singleton, twin and triplet pregnancies

Tests & Diagnosis for Gestational Diabetes

How to Cut Risk of High Blood Sugar When You’re Pregnant