Diabetes in Pregnancy

Question 1

Diagnosis of GDM

Answer 1

Fasting glucose >7.0 mmol

2h OGTT >7.8mmol

Question 2

Complications of GDM

Answer 2

Categorised: Maternal and Fetal

Maternal
Immunologicaly Related
UTI
Wound and endometrial infection

CVS Related
PET
Pre-existing hypertension in overt diabetics (25%)
IHD worsens

Birth Related
C-section/ instrumental delivery more likely due to fetal compromise and increased fetal size

Fetal
Birth Related (PISS BNR)
Increased birthweight (macrosomia) >5kg
Preterm labour (10%)
Shoulder dystocia and birth trauma 
Stillbirth
Neonatal hypoglycaemia
RDS

Antenatal Related
Polyhydramnios (due to marcosomia)
Fetal compromise: fetal distress and sudden fatal death are more common and related to poor contorl in 3rd trimester

Pre-existing diabetes: Diabetic nephropathy associated with poor fetal outcomes
Diabetic retinopathy often deteriorates

Question 3

Risk Factors for GDM

Answer 3

The 3 Ps, FBE

Previous macrosomic baby
Previous unexplained still birth
Previous GDM

First-degree relative with DM
BMI>30
South Asian, Black Caribbean or Middle Eastern

Question 4

Screening for GDM

Answer 4

NICE recommendation: 28 week GTT

If previous GDM –> GTT at 18 weeks

ALSO
If polyhydramnios or persistent glycosuira –> GTT

Question 5

Management of Pre-Existing DM in Pregnancy

Answer 5

Preconceptual Care
Asses renal function, BP and retina
Optimise glucose control
folic acid 5mg/day
Labetolol or methyldopa as anti hypertensive 

Monitoring
HbA1c Aim <7%
Fortnight visits up to 34 weeks, then weekly
Home glucose monitoring
Ideally below 6 mmol/L

Fetal Monitoring
Normal USS + additional scans (every 4 weeks)
Umbilical artery Doppler (If IUGR or PET)
Fetal echo

Monitoring complications
Renal function
Retinal checks
75mg Daily Aspirin

Delivery
Delivery by 39 weeks
Elective caesarean section of estimated weight >4kg
Sliding scale of insulin and dextrose infusion during labour

Neonate and Pueperium
Neonatal Hypoglycaemia
RDS (even after 38 weeks)