Gestational diabetes Flashcards
What is gestational diabetes?
Any degree of glucose intolerance with onset or first recognition during pregnancy
Transient resistance occurs in pregnancy, an effect of the high concentration of pregnancy hormones which act as antagonists to insulin action
What is happening to the incidence of gestational diabetes?
Increasing
What is the incidence of gestational diabetes?
1 in 5
When does gestational diabetes occur?
When the body is unable to produce enough insulin to meet the needs of the pregnancy
What happens to insulin resistance during pregnancy
Progressive insulin resistance - higher volume of insulin is needed in response to a normal level of blood glucose
Insulin requirements increase by 30% during pregnancy
List the risk factors for poor pancreatic reserve
BMI>30 Asian ethnicity Previous gestational diabetes 1st degree relative with diabetes Polycystic ovarian syndrome Previous macrocosmic baby >4.5kg
List the clinical symptoms of gestational diabetes
Asymptomatic
Polyuria
Polydipsia
Fatigue
List the foetal complications of gestational diabetes
Macrosomia - shoulder dystocia, obstructed/delayed labour, higher rates of instrumental delivery Organomegaly - cardiomegaly Erythropoiesis - polycythaemia Polyhydramnios Increased rates of pre-term delivery
What is insulin
A hormone that has similar structure to growth promotors
How does gestational diabetes cause foetal hyperinsulinemia
Glucose is transported across the placenta but insulin is not
Causes foetal hyperglycaemia and to compensate the foetus increases its own insulin levels to compensate
What is the foetus at risk of after delivery and why?
Hypoglycaemia - high insulin levels but no more glucose from the mother
Transient tachypnoea of the newborn - high insulin causes a reduction in pulmonary phospholipids which in turn decreases foetal surfactant production. Reduces the surface tension in alveoli
What is important to prevent/help with hypoglycaemia after birth in the baby?
Regular feeding
What investigations are there for gestational diabetes
Oral glucose tolerance test
Describe the oral glucose tolerance test
Fasting pladma glucose is measured, then a 75g glucose drink is given with a repeat plasma glucose measurement after 2hrs
How is GDM diagnosed?
If fasting glucose >5.6mmol/L or 2hr post prandial glucose >7.8mmol/L
When is OGTT offered in the UK?
Booking - if previous gestational diabetes
24-28 weeks - if risk factors present
At any point during pregnancy - if +2 glycosuria on one occasion or ?1 on 2 occasions
Describe the management of gestational diabetes
Lifestyle - diet and exercise
4x daily cap glucose measurements
Medical - metformin, glibenclamide (if metformin not tolerated)
Insulin - if fasting glucose >7
Consultant led care
Growth scans
Aim to deliver 37-38 weeks
What is the main side effect of metformin?
GI disturbance
Describe the post-natal care of gestational diabetes
Anti-diabetic medication stopped immediately after delivery
Check blood glucose before discharge
6-13 weeks post partum - fasting blood glucose test - increased risk of developing diabetes in the future
In subsequent pregnancies, OGTT offered at booking and 24-28 weeks gestation
What is diabetes?
Metabolic disorder characterised by raised plasma concentrations of glucose, amino acids and fats
Name and describe the two types of diabetes
T1DM - reduction in production and release of insulin from the pancreas
T2DM -reduction in the sensitivity to insulin in the body’s organs and tissues
For women who already have pre-existing diabetes what should the sugar and HBA1c levels be before pregnancy?
Aim for HBA1C <48mmol/mol
Fasting <5mmol/l
1 hour post-prandial <7.0mmol/L
What percentage risk of congenital abnormality does a HBA1C >86mmol/mol indicate?
25%
What measures should be taken before pregnancy in a patient with pre-exisiting diabetes?
Ready, set, go
- Review medication - stop statins/ACEi
- renal and retinal assessment every trimester
- Folate prescription 3months in advance - 5mg OD - pre and for 1st trimester
- HBA1C aim <48mmol/mol - optimise glucose control
- Aspirin 150mg - decrease risk of PET
- Serial growth scans
- Foetal echo at 18weeks
- IOL 37-38+6 weeks
What are the maternal risks from pre-existing diabetes?
Hypos Deterioration of retinal/renal health Infection Pre-eclampsia Birth trauma Induction of labour C-section
What are the foetal risks from pre-existing diabetes?
Miscarriage Congenital malformation Stillbirth Prematurity Macrosomia Neonatal hypoglycaemia Neonatal death Obesity and/or diabetes in later life
What treatment is given intrapartum for pre-existing diabetes
Variable rate IV insulin infusion - VRIII (sliding scale) <7mmol/L
Describe the post natal care for women with pre-existing diabetes
T2DM resume taking metformin and glibenclamide while breast feeding
Look out for neonatal hypoglycaemia
Contraception
