Diabetes in Pregnancy Flashcards
What are the antepartum risks associated with pre-existing diabetes in 1st trimester
Miscarriage Congenital malformations (e.g. sacral agenesis)
What are the antepartum risks associated with diabetes in pregnancy later on in gestation?
Pre-eclampsia
Macrosomia (large for gestational age)
Polyhydramnios (foetal polyuria)
Intrauterine death
What are the intrapartum risks associated with diabetes in pregnancy?
Stillbirth
Shoulder dystocia
What are the postpartum risks associated with diabetes in pregnancy?
Neonatal hypoglycaemia - because used to high glucose levels from mother
Diabetes risks: mnemonic
SMASH Shoulder dystocia Macrosomia Amniotic fluid excess Stillbirth Hypertension (pre-eclampsia) and neonatal hypoglycaemia
What are the mechanisms of late complications?
Maternal hyperglycaemia –> Foetal hyperglycaemia –>
Foetal hyperglycaemia results in:
- Foetal macrosomia b/c insulin = growth factor + sugar –> increased fat
- Foetal hyperinsulinaemia = because the foetal hyperglycaemia causes pancreas to be turned up higher than normal leading to hyperinsulinaemia
Foetal macrosomia –> leads to shoulder dystocia
Foetal hyperinsulinaemia –> Neonatal hypoglycaemia - b/c too much insulin for levels present once maternal glucose removed at birth
How can the risks of diabetes in pregnancy be significantly reduced?
By optimising control
How should pregnancies in patients with diabetes be treated?
As high risk and monitored closely
What are the NICE 2015 guidelines regarding pre-existing diabetes in pregnancy?
Impact on pregnancy starts from pre-conception
So need to start high dose folic acid (5mg daily) from 6 weeks pre-conception
Don’t stop contraception until good control achieved - HbA1c < 48mmol/mol
Monitor eyes and renal function carefully during pregnancy
What is the risk if poor control (HbA1c >86mmol/mol)?
Very high risk of congenital malformations (avoid pregnancy)
Diagnosis of pre-existing diabetes
Already likely to have a diagnosis / but not always
Confirmed with oral glucose tolerance test (OGTT)
When should you suspect diabetes?
If there is persistent glycosuria in first trimester and high random blood sugars on testing
Does a first trimester presentation suggest pre-existing or gestational diabetes?
Pre-existing
What are the effects of pre-existing diabetes on pregnancy?
Increased insulin requirement (insulin resistance increases in all pregnancies)
Acceleration of retinopathy
Deterioration of renal function if pre-existing nephropathy - can manifest as hypertension
Maternal hypoglycaemia in early pregnancy - can lose awareness to this, especially if morning sickness etc
What are the principles of management in pre-existing diabetes?
Pre-conceptual counselling - improved control reduces risk
Manage with diabetes team - alter medications to optimise control
Stop ACE inhibitors and statins - these are teratogenic
Screen for and monitor vascular complications
Early viability scan (because increased risk of miscarriage)
Detailed anomaly scan - increased risk of sacral agenesis where the bottom part of the neural tube does not form properly
What is gestational diabetes?
Diabetes with its initial onset/ first recognised in pregnancy
When is gestational diabetes most likely to impact the pregnancy?
In the second trimester
Are macro- or micro- vascular complications present?
No
What is the pathophysiology behind gestational diabetes?
Increased insulin requirement plus increased insulin resistance pushes the body into a temporary diabetic state
What factors result in Insulin resistance?
Increased calorie intake Reduced exercise Increased fat deposition Placental lactogen & placental progesterone rise in 2nd trimester Increased cortisol and GH in pregnancy
What is used to screen selected women for gestational diabetes at 28 weeks
Oral glucose tolerance test
What comprises an oral glucose tolerance test?
Fasting venous plasma glucose measured
75g oral glucose load administered
Venous plasma glucose is measured at 2hrs
HbA1c is used for diagnosis of diabetes in pregnancy - true or false?
False - it is not used
What are the NICE guidelines for glucose levels in the diagnosis of gestational diabetes?
Fasting glucose >5.6mmol/mol
Two hour glucose >7.8mmol/mol
