Gestational Diabetes: Causes, Risk Factors and Symptoms
Learn about gestational diabetes, including its causes, risk factors, and symptoms, to better understand this pregnancy-related condition.
Written by Dr. Rohinipriyanka Pondugula
Reviewed by Dr. D Bhanu Prakash MBBS, AFIH, Advanced certificate in critical care medicine, Fellowship in critical care medicine
Last updated on 13th Jan, 2026
Introduction
Gestational diabetes mellitus (GDM) is a type of diabetes that develops exclusively during pregnancy, affecting how your cells use sugar (glucose). It causes high blood sugar that can impact your pregnancy and your baby's health. While this diagnosis can feel overwhelming, understanding its roots is the first step toward effective management. This condition arises from a perfect storm of hormonal changes and underlying pre-pregnancy factors that disrupt your body's ability to manage glucose effectively. The good news is that with careful monitoring and treatment, you can have a healthy pregnancy and a healthy baby. This article will demystify the causes, highlight the often-subtle signs, and outline the key risk factors so you can feel informed and empowered on your journey.
What Exactly is Gestational Diabetes?
Gestational diabetes is characterised by high blood sugar (hyperglycaemia) that is first recognised during pregnancy. Unlike type 1 or type 2 diabetes, it is directly triggered by the physiological changes of pregnancy and typically resolves after the baby is born. However, it requires careful attention as it can pose risks to both mother and child if not properly managed.
How Pregnancy Changes Your Body's Sugar Processing
During pregnancy, your body naturally becomes more resistant to insulin. This is a normal adaptation to ensure that the growing baby gets enough glucose, its primary fuel source. To compensate, a healthy pancreas will produce extra insulin to overcome this resistance. Gestational diabetes develops when the pancreas cannot secrete enough insulin to meet this increased demand, leading to a buildup of sugar in the bloodstream.
Consult an Obstetrician and Gynaecologist for the best advice
The Root Causes: Why Gestational Diabetes Develops
The development of GDM isn't due to a single factor but rather a combination of hormonal activity and the body's response to it.
The Role of The Placenta and Hormones
The placenta, which nourishes your baby, also produces a variety of hormones essential for sustaining the pregnancy. Some of these hormones, such as human placental lactogen, cortisol, and oestrogen have a blocking effect on insulin, a condition known as insulin resistance. This effect becomes more pronounced as the placenta grows larger in the second and third trimesters.
Insulin Resistance: The Core Problem
Insulin resistance means your body's cells don't respond as effectively to insulin. Normally, insulin acts like a key, unlocking cells to allow glucose to enter and be used for energy. When you are resistant, the "key" doesn't work as well, so glucose remains in the bloodstream instead of being absorbed by the cells.
When The Pancreas Can't Keep Up
In most pregnant women, the pancreas responds to this resistance by working overtime to produce up to three times the normal amount of insulin. However, in approximately 2-10% of pregnancies, the pancreas can't keep pace with the demand. This insulin deficit is what ultimately leads to the high blood sugar levels that define gestational diabetes.
Who is Most at Risk? Understanding The Risk Factors
While any pregnant person can develop GDM, certain factors significantly increase the likelihood. It's important to note that many women with gestational diabetes have no known risk factors.
Pre-Pregnancy Health Factors
Overweight or Obesity: A Body Mass Index (BMI) of 30 or higher is a major risk factor.
Prediabetes: Slightly elevated blood sugar levels before pregnancy can indicate a higher risk.
Family History: Having a parent or sibling with type 2 diabetes increases your risk.
Previous Large Baby: Giving birth to a baby who weighed more than 9 pounds (4.1 kilograms) previously.
Previous Gestational Diabetes: A history of GDM in a prior pregnancy significantly raises your risk in subsequent ones.
Polycystic Ovary Syndrome (PCOS): This condition is linked to insulin resistance.
Genetic and Demographic Factors
Age: Women over the age of 25 are at higher risk.
Race/Ethnicity: Women who are Black, Hispanic, American Indian, or Asian American have a higher predisposition to developing gestational diabetes.
Pregnancy-Related Risk Factors
Excessive Amniotic Fluid (Polyhydramnios): This can sometimes be a consequence or a sign of GDM.
Rapid Weight Gain During Pregnancy: This can exacerbate insulin resistance.
If you identify with several of these risk factors for diabetes in pregnancy, it's especially important to attend all your prenatal appointments for recommended screening. A doctor can help you assess your personal risk and create a plan for a healthy pregnancy.
Recognising The Signs and Symptoms of Gestational Diabetes
One of the most challenging aspects of GDM is that it often presents with no noticeable symptoms. When symptoms do occur, they are typically mild and can be mistaken for normal effects of pregnancy.
Common Symptoms (Often Mild or Absent)
Increased thirst (polydipsia)
Frequent urination in large amounts (more than the typical frequent urination of pregnancy)
Fatigue (common in all pregnancies)
Sugar in the urine (detected during a prenatal visit)
Nausea
Blurred vision
Frequent infections, such as bladder or skin infections
Why Screening is Crucial: The Glucose Tolerance Test
Because signs of gestational diabetes in the third trimester can be silent, universal screening between 24 and 28 weeks of pregnancy is standard medical practice. This involves drinking a sugary solution and having your blood drawn at intervals to measure how your body processes the glucose. This is the most reliable way to detect GDM.
Proactive Management and Healthy Pregnancy Outcomes
A diagnosis is not a failure; it's an opportunity to take control of your health and your baby's well-being. Effective managing gestational diabetes dramatically reduces associated risks.
Dietary Changes and Blood Sugar Monitoring
The cornerstone of management is a balanced diet for managing gestational diabetes, focused on complex carbohydrates, lean proteins, and healthy fats spread throughout the day. You will likely be asked to check your blood sugar levels four times a day (fasting and after meals) to understand how food and activity affect you.
The Importance of Exercise
Regular physical activity helps your body use glucose without extra insulin. Activities like walking, swimming, or prenatal yoga can significantly improve blood sugar control.
When Medication or Insulin is Needed
If diet and exercise aren't enough to keep your blood sugar within the target range (which is the case for about 10-20% of women), medication or insulin therapy may be necessary. Insulin is the most common medication, as it does not cross the placenta. If your blood sugar levels remain consistently high despite lifestyle changes, consult a doctor online with Apollo24|7 to discuss the best treatment plan for you. They can connect you with endocrinologists who specialise in diabetes management during pregnancy.
Conclusion: Empowerment Through Knowledge and Care
Understanding what leads to gestational diabetes demystifies the condition and transforms a diagnosis from a scare into a manageable aspect of your pregnancy. It is a clear signal from your body to pay close attention to your blood sugar levels. By working closely with your healthcare team, which may include your obstetrician, an endocrinologist, and a dietitian, you can effectively manage your glucose levels through tailored nutrition, safe physical activity, and consistent monitoring. This proactive approach empowers you to significantly reduce potential risks, ensuring the best possible outcome for both you and your baby. Remember, this is a temporary chapter, and with the right knowledge and support, you are fully capable of navigating it successfully.
Consult an Obstetrician and Gynaecologist for the best advice
Consult an Obstetrician and Gynaecologist for the best advice
Dr Chanda Chowdhury
Obstetrician and Gynaecologist
23 Years • MBBS, DNB (Obstetrics & Gynaecology)
Kolkata
Apollo Multispeciality Hospitals , Kolkata, Kolkata
(200+ Patients)
Dr. K Anusha
Obstetrician and Gynaecologist
4 Years • MBBS, DGO
Yemmiganur
SRINIVASAA HOSPITAL, Yemmiganur
Dr. Mona Yadav
Obstetrician and Gynaecologist
19 Years • MBBS, MD (Obstetrics & Gynaecology)
Dombivli
Nulife multispeciality, Dombivli
Dr. Parul Sharma
Obstetrician and Gynaecologist
8 Years • MBBS, MS (Obstetrics & Gynaecology)
New Delhi
THE DOCTORS NESST, New Delhi
Dr. Debajyoti Goswami
Obstetrician and Gynaecologist
10 Years • MBBS,D.G.O(DNB),Adv. Infertility Tech.(AIIMS, Delhi),Fellowship in Diabetes(U.K),Comprehensive Abortion Care(Govt. Of W.B), Certificate in Clinical Embryology(AIIMS, BHUBANESWAR)
Bankura
D.G Clinic, Bankura
(25+ Patients)
Frequently Asked Questions
1. Can you get gestational diabetes without any risk factors?
Yes, it is possible. While risk factors increase the likelihood, some women with no known risk factors still develop gestational diabetes. This is why universal screening around 24-28 weeks is a standard part of prenatal care for everyone.
2. What is the main difference between type 2 and gestational diabetes?
The key difference is timing and cause. Type 2 diabetes is a chronic condition influenced by genetics, lifestyle, and other factors, and exists outside of pregnancy. Gestational diabetes is specifically induced by the hormonal changes of pregnancy and typically resolves after delivery. However, having GDM significantly increases your risk of developing type 2 diabetes later in life.
3. Does gestational diabetes mean my baby will be born with diabetes?
No. Gestational diabetes does not mean your baby will be born with diabetes. However, uncontrolled high blood sugar can cause the baby to produce extra insulin, leading to high birth weight, low blood sugar after birth, and other complications. Proper management greatly reduces these risks.
4. What does the gestational diabetes test feel like?
Most women find the glucose drink to be very sweet, similar to a flat soda or a melted popsicle. Some feel slightly nauseous, dizzy, or jittery afterwards due to the rapid sugar spike. It's generally well-tolerated, and bringing something to distract yourself (like a book or music) can help.
5. How can I prevent gestational diabetes in my next pregnancy?
You can't guarantee prevention, but you can lower your risk by entering pregnancy at a healthy weight, eating a balanced diet rich in fiber and low in processed sugars, and engaging in regular physical activity before and during pregnancy. If you had GDM before, Apollo24|7 offers a convenient home collection for tests like HbA1c to monitor your blood sugar levels before conceiving again.