Gestational Diabetes Mellitus

By Dr. Anuradha Kapur in Obstetrics And Gynaecology

Jan 10 , 2022 | 2 min read

Gestational diabetes mellitus is the most common metabolic disorder of pregnancy and a major public health concern in India with rising incidence.

GDM is defined as carbohydrate intolerance resulting in increase in blood sugar of variable severity with onset or first recognition during pregnancy.

Asians and moreover Indians are at a greater risk of Diabetes mellitus and hence of gestational diabetes.

GDM is associated with an increased risk of adverse outcomes for both mother and baby. Both short term and long term

Maternal Complications – Maternal risks of GDM include :

Increase fluid in the amniotic sac
High blood pressure
Prolonged Labour,
Obstructed Labour
Increased rates of Caesarean Section
Post-partum haemorrhage
Infection

Foetal risks include :

Abortion
Intra-uterine death
Stillbirth
Congenital malformation
Shoulder dystocia
Birth injuries due to babies, which are large for gestational age
Neonatal decrease in blood sugar and infant respiratory distress syndrome

There is also growing evidence that GDM is associated with an increased risk of long-term ill-health outcomes in the mother (type 2 diabetes mellitus and cardiovascular disease) and offspring (childhood obesity and associated cardio-metabolic risks in later life.

Some risk factors associated with GDM :

Physical inactivity
Previous pregnancy history of:

GDM
Macrosomia (≥ 4000 g)
Stillbirth

Hypertension (140/90 mm Hg or being treated for hypertension)
Dyslipidaemia
Maternal age more than 40 years
Ethnicity- high risk races (In Indians)
Past History of PCOS
Morbid obesity

TESTING PROTOCOL Universal testing of all pregnant women is recommended in India.

The first blood sugar testing should be done during first antenatal visit itself. The second testing should be done during 24-28 weeks of pregnancy if the first test is negative as many pregnant women develop blood sugar intolerance during this period (24-28 weeks). Repeat testing in 3rd trimester as per clinicians advice.

Management of GDM Guiding Principles :

All Pregnant women who test positive for GDM for the first time should be started on Medical Nutrition Therapy (MNT) and physical exercise.

Walk/exercise for 30 minutes a day.
GDM is if it is not controlled with MNT and (lifestyle changes), Metformin or Insulin therapy is added.
Diet should be balanced.
Additional 350 kcal are added as requirement during pregnancy.

Blood Sugar Targets in Pregnancy: self-monitoring of blood glucose is recommended in gestational diabetes mellitus to achieve optimal Glucose levels. Glucose targets are:

Fasting plasma glucose less than 95 mg%.
One hour post meals levels < 140 mg %
2 hour post meals <120 mg%

The timing of delivery should be individualized by the obstetrician depending on blood sugar control & other factors.

Vaginal delivery is preferred and LSCS is done for obstetric indications only.

Post-delivery follow up of pregnant women with GDM :

Pregnant: women with GDM and their offspring’s are at increased risk of developing Type II Diabetes mellitus in later life and should have blood sugar testing 6 weeks after delivery They should be counselled for healthy lifestyle particularly role of diet & exercise. Early diagnosis and treatment of GDM can decrease adverse pregnancy outcomes and significantly improve health of mother and baby.