What gestational diabetes is

GDM is defined as glucose intolerance that is first recognised during pregnancy. The placenta produces hormones that naturally make cells more resistant to insulin as pregnancy progresses. In most women, the pancreas compensates by producing more insulin. In women who develop GDM, the compensation is not enough and blood sugar rises.

India has one of the highest rates of GDM in the world — estimated at 10–15% of all pregnancies in urban populations, according to estimates from the Diabetes in Pregnancy Study Group of India (DIPSI). South Asian women have higher risk than European women at equivalent weights and body mass indexes.

Why GDM needs to be found and treated

Untreated or poorly controlled GDM increases the risk of:

• Macrosomia — a large baby (over 4 kg), making delivery difficult and increasing the chance of shoulder dystocia and emergency caesarean section
• Preeclampsia — dangerous rise in blood pressure in the mother
• Preterm birth
• Neonatal hypoglycaemia — the baby’s blood sugar drops sharply at birth after adapting to the mother’s high glucose
• Increased caesarean section rate
• Future risk for the mother — approximately 50% of women with GDM develop Type 2 diabetes within 10 years
• Future risk for the child — higher likelihood of obesity and metabolic syndrome in adolescence

With proper management, most of these risks are substantially reduced.

Screening: who needs the OGTT test and when

All pregnant women at Apex are offered glucose screening at 24–28 weeks of pregnancy. This is the window when insulin resistance peaks.

• DIPSI method (75g, one-step): a 75g glucose drink is given regardless of fasting state; blood is drawn at 2 hours. A 2-hour value at or above 140 mg/dL diagnoses GDM. This is the method recommended by the Diabetes in Pregnancy Study Group of India and widely used in Indian hospitals.
• WHO/ADA 2-step method: a 50g non-fasting screening test first; if elevated, a formal 75g fasting OGTT follows.

Women at higher risk — obesity, previous GDM, family history of diabetes, previous large baby, polycystic ovary syndrome, previous stillbirth — should be screened earlier, from the first trimester.

Management: what happens after diagnosis

Step 1: Dietary changes

A diabetic diet is the first treatment and controls blood sugar adequately in about 70–80% of women with GDM. Key principles: consistent carbohydrate at each meal, avoiding sugary drinks and fruit juice, spacing meals, choosing complex carbohydrates over refined ones, and continuing the nutritional adequacy the baby needs. A dietitian referral is advised where available.

Step 2: Blood sugar monitoring

You will be asked to monitor blood sugar at home using a glucometer — fasting and 1 or 2 hours after each main meal. Targets: fasting below 95 mg/dL, 1-hour post-meal below 140 mg/dL, 2-hour post-meal below 120 mg/dL. Record the readings and bring them to each antenatal visit.

Step 3: Medication if needed

If diet and monitoring alone do not achieve targets within one to two weeks, medication is added. Metformin is widely used in Indian practice and crosses the placenta, though with no proven harm. Insulin is preferred by many guidelines for reliable glucose control and does not cross the placenta. The choice is made by the treating doctor based on your specific readings, other medications and your preference.

Antenatal monitoring

Women with GDM need more frequent antenatal visits than the standard schedule, including growth scans to detect macrosomia and additional monitoring of the baby’s wellbeing. The Maternity and Delivery team at Apex coordinates this.

Delivery

GDM alone is not an indication for caesarean section. The decision depends on the size of the baby, the cervical status and labour progress. During labour, blood sugar is monitored closely. After delivery, blood sugar typically returns to normal within 24–48 hours and medication is stopped.

After delivery: follow-up is not optional

GDM usually resolves after delivery, but it is not forgotten. You should have a 75g OGTT at 6–12 weeks after delivery to confirm that blood sugar has returned to normal. After that, annual fasting blood glucose or HbA1c for life — because the lifetime risk of developing Type 2 diabetes is approximately 50%.

If you are diagnosed with Type 2 diabetes at this post-partum screen, the Diabetes Clinic takes over ongoing management.

Frequently asked questions

Is gestational diabetes dangerous?

It increases several risks — large baby, difficult delivery, preeclampsia, neonatal hypoglycaemia — but with detection and management those risks are substantially reduced. The majority of women with well-managed GDM have normal deliveries and healthy babies.

Will I always have diabetes after pregnancy?

GDM resolves after delivery in most women. However, it is a strong predictor of Type 2 diabetes later in life — roughly 50% of women with GDM develop Type 2 within 10 years. Annual screening after pregnancy is strongly recommended.

Can I eat fruit if I have gestational diabetes?

Yes, but in controlled portions. High-sugar fruits — mango, grapes, banana, chikoo — should be limited. Lower-sugar fruits — guava, apple, pear — are better choices. Timing matters too — a small amount with a meal is better than a large amount alone as a snack.

Do I need insulin in gestational diabetes?

Not always. About 70–80% of women with GDM control blood sugar adequately with diet alone. Of those who need medication, metformin or insulin is used. Insulin does not cross the placenta and is considered safe in pregnancy.

Does gestational diabetes affect the baby?

If uncontrolled, the main risk is a large baby (macrosomia), which can make delivery more difficult and increases the risk of shoulder dystocia. After birth, the baby’s blood sugar may drop (neonatal hypoglycaemia) and is monitored. With good control during pregnancy, outcomes are similar to pregnancies without GDM.

How many times do I need the OGTT test?

Once, at 24–28 weeks for most women. Earlier testing if you have risk factors. If the result is normal, the test is not usually repeated unless symptoms develop.

My fasting blood sugar in the morning is normal but post-meal sugar is high. Is this GDM?

A high post-meal value with a normal fasting value is a form of glucose intolerance. Formal OGTT criteria should be applied — discuss with your gynaecologist.

Can I have a normal delivery with gestational diabetes?

Yes, in most cases. GDM alone does not require caesarean section. The decision depends on the baby’s size, labour progress and other factors.

Book an antenatal consultation

Call +91 85912 35064 or book an appointment online. Apex Multispeciality Hospital, Sector 19, near MSEB, Kopar Khairane, Navi Mumbai 400709.