Diabetes During Pregnancy , risk factors and methods to control it

What is Gestational Diabetes?, How to Detect it? and How to Manage it?

- Dr. Farhath Thara

MBBS, PGDFM and FCD(Family Physician and Diabetologist)

GDM is defined as glucose intolerance first recognized in pregnancy and includes previously undiagnosed diabetes or impaired Glucose intolerance. Women with pre-existing diabetes have a higher prevalence of essential hypertension. In addition, there is a 40–45% risk of developing hypertensive disorders of pregnancy.

Risk factors of GDM include obesity, family history of type 2 DM and GD, a macrosomic infant, unexplained stillbirth or neonatal death during the previous pregnancy.

Diabetes in pregnancy poses numerous problems for both mother and foetus.

 Type 1 diabetes is more strongly associated with development of pre-eclampsia, and type 2 with essential hypertension. Long-term outcomes for women with GDM include increased risk in developing type 2 diabetes mellitus, metabolic syndrome, as well as cardiovascular diseases.

. The most Type 1 diabetic women can now expect to become the mother of healthy children. In the developing world maternal morbidity and perinatal mortality remain several times higher than the non-diabetic pregnancy.

Normal pregnancy induces insulin resistance, comparable to that in type 2 DM through the diabetogenic effects of placental hormones and progesterone. The effect is maximal in the late 2^nd and 3^rd trimesters.

Two generations are at risk in developing diabetes in future – mother herself and offspring.

SCREENING STRATEGIES FOR GESTATIONAL DIABETES

Screening programs require significant health resources, infrastructure, and functional health systems to be effective”

When to Screen:       

At 24^th – 28^th weeks of gestation.

Recent concept – Screen at 16^th week of gestation, if negative 24^th – 28^th week of gestation and finally 32^nd – 34^th week.

The screening is ideally performed after a woman’s initial prenatal visit and has been focused on women with risk factors for hyperglycemia. Risk factors for patient selection for early screening do vary internationally, however the most consistent is previous history of gestational diabetes.

Screening Method:

WHO Criteria (Plasma Glucose):

(FPG – Fasting Plasma Glucose)

A Standard OGTT (Oral Glucose Tolerance Test) should be performed after over night fasting by giving 75g of glucose. Plasma Glucose is measured at fasting and after 2 hours. Pregnant women who meet WHO criteria for IGT (2hr PG > 140mg/dl) are classified as having gestational diabetes mellitus (GDM).

 If the patient has fasting plasma glucose more than 126 mg and /or 2 hr post glucose more than 200 mg (in the first trimester itself), probably she has been having undetected diabetes prior to conception (pre gestational Diabetes) and can be confirmed by A1c estimation.

Management:

• Patient Education
• Medical Nutrition Therapy
• Insulin Therapy
• Target Blood glucose levels

A team approach is ideal for managing women with GDM.

Patient Education:

The importance of educating women with GDM and their family members about the condition and its management cannot be overemphasized. The compliance with the treatment plan depends on the patient’s understanding of

• The implications of GDM for baby and herself.
• The dietary and exercise recommendation
• Self-monitoring of blood glucose
• Self-administration of insulin
• Incorporate safe physical activity
• Development of techniques to reduce stress

MNT

All women should receive nutritional counselling. The meal pattern should provide adequate calories and nutrients to meet needs of pregnancy. The expected weight gain during pregnancy is 300-400gm/week and total weight gain is 10-12kg per term. The aim of meal plan should provide sufficient calories to maintain adequate nutrition for the mother and foetus and to avoid excess weight gain. Calorie requirement depends on age, activity, pre-pregnancy weight and pregnancy stage.

Insulin Therapy

Patients with Type 2 diabetes are usually advised to take insulin injections. These injections can be self-administered with proper consultation and guidance from diabetic nurse or healthcare provider.

Insulin dosage usually increases throughout pregnancy, particularly up to 30 weeks of gestation. After this, the requirement declines. The ideal insulin is human insulin. Insulin is stopped when labour starts.

 Monitoring of glycemic Control

Glycemic control is the optimal serum glucose concentration in diabetes patients. The success of treatment of a lady with GDM depends upon glycemic control maintained throughout pregnancy. For this monitoring of glycemic control is very important. Nowadays, monitoring of blood glucose levels has become very easy and effective with the latest glucose monitors. There are many latest apps in the market that help in regulating blood glucose levels. Patients can now collaborate with the healthcare providers through these apps and optimize their blood sugar levels.

 Once target level is achieved, monitoring of FPG (Fasting Plasma Glucose) and PPPG (Post Prandial Plasma Glucose) should be done once a month till 28^th week of gestation: after that period, once in 2 weeks and once a week till delivery. Glycosylated haemoglobin: if the glucose intolerance is detected in the early pregnancy, HbA1C is helpful to differentiate between pregestational diabetes and GDM. If the HBA1C level is 6, she is likely to be a pre GDM. HbA1C is useful in monitoring the glucose control in pregnancy, but not for the day-to-day management. 

Measuring Other Parameters

Blood pressure monitoring in every visit is very important. Fundus examination, estimation of microalbuminuria, ultrasound measurement of the foetus are the important aspects.

Obstetric Considerations like foetal evaluation, timing of delivery, intra partum and delivery management, breast feeding etc. are to be monitored carefully.

Follow Up of GDM

GDM recurs approximately in 50% of subsequent pregnancies. The future of developing diabetes for a Gestational Diabetic is twofold, if she becomes over weight.

The maternal an fetal outcome depends upon the care by the committed team of diabetologists, dieticians, obstetricians and neonatologists. A short-term intensive care gives a long term pay off in the primary prevention of obesity, impaired glucose tolerance and diabetes in the baby.