Diabetes in Pregnancy

Gestational Diabetes Mellitus (GDM) commonly called as Diabetes in Pregnancy is defined as any degree of glucose intolerance appearing or first being recognized during pregnancy. Of the many forms of diabetes, the prevalence of gestational diabetes is on the rise in India with about 3 million cases diagnosed annually. In this condition, a non-diabetic woman develops high blood sugar levels during pregnancy after about 24 weeks. The pregnancy hormones cause insulin resistance due to which glucose is utilized less effectively. Some factors responsible for the increasing prevalence of gestational diabetes in women include Indian ethnicity, polycystic ovarian syndrome (PCOS), obesity, poor dietary habits, and stress. Women with GDM must consult Endocrinologist for optimal management of diabetes.

GDM is clinically important because of its immediate and long term risks and complications. There is a future risk of type 2 Diabetes Mellitus in mother and risk of Obesity and Diabetes in children. In addition to the future risk of diabetes in mother and children, during the pregnancy, there is increased risk of complications in fetus, newborn baby and mother like preterm delivery, hypertension, increased birth weight of babies, etc. Treatment of even mild forms of GDM reduces these complications.

GDM must be screened at first ante-natal visit and if reports are normal must be repeated at 24 weeks gestation. GDM is diagnosed by IADPSG criteria if either fasting glucose more than 92mg/dl, 1 hour glucose more than 180mg/dl or 2 hour value more than 153mg/dl. Endocrine Society also endorses the IADPSG criteria for the diagnosis of GDM.

Every woman with GDM needs advice on medical nutrition therapy and lifestyle changes. Walking for 15 – 30minutes after each major meals improve the blood sugar control. If there is no response to changes in diet and lifestyle, then medicines (insulin, metformin and glyburide) are required to control the blood sugar. Although metformin and glyburide are effective in controlling mild forms of diabetes in pregnancy, long term effects of these medicines on baby are not known and not recommended by few societies. Insulin is safe as it dose not cross placenta to the baby unlike the other two oral medicines.

It is also imperative for pregnant women with diabetes to follow a healthy diet and take insulin injections regularly to keep the blood sugar under control (fasting below 95 and 1hour post meal below 140). Self-monitoring of blood glucose (SMBG) is the cornerstone of diabetes management in GDM.

GDM must follow up closely in consultation with Endocrinologist for appropriate treatment and management of diabetes for better outcomes. One-third to two-thirds of women with GDM will have GDM in a subsequent pregnancy. Women with GDM needs screening for diabetes 2-3months after delivery as advised by their endocrinologist. Women with a history of gestational diabetes mellitus found to have prediabetes should receive intensive lifestyle interventions or metformin to prevent diabetes in consultation with their Endocrinologist.

Dr.S.Ramkumar
MD DNB (Endocrinology) DM (Diabetes & Endocrinology) AIIMS
Clinical Fellowship in Diabetes (Auckland, NZ)
Endocrinologist & Diabetologist,
Madras Medical College & Apollo Hospitals
Dr.Rams’Diabetes & Endocrine Clinic, Anna Nagar, Chennai