Diabetes In Pregnancy Flashcards
Percentage of women with pre-existing or gestational diabetes in pregnancy?
5% (87.5% gestational, 7.5% type 1, 5% type 2)
Risks in pregnancy associated with pre-existing diabetes
Higher risk of: Miscarriage Pre-eclampsia Preterm labour (5x more likely) Diabetic retinopathy can worsen rapidly Congenital malformations Stillbirth Macrosomia Perinatal mortality Postnatal adaptation problems
How to diagnose gestational diabetes?
Fasting glucose >5.6 mol/litre
2 hour plasma glucose >7.8 mmol/litre
What is shoulder dystocia?
Vaginal cephalic delivery that requires additional obstetric manoeuvres to deliver the foetus after the head has delivered and gentle traction has failed
Anterior or posterior fetal shoulder impacts on maternal symphysis or sacral promontory, respectively
How should shoulder dystocia be managed?
McRoberts’ manoeuvre (flexion and abduction of the maternal hips)
Suprapubic pressure applied
Episiotomy is not always necessary
Reason for macrosomia
Maternal glucose high - enters baby’s blood stream, drives the release of insulin - stimulates fat storage, causes organ growth
What is hPL?
Human placental lactogen
What happens in gestational diabetes?
hPL, GH, cortisol, progesterone cause increased production of glucose
hormones also cause insulin resistance
Who should be screened for GDM
>30 BMI Previous baby >4.5kg Previous GDM FH (first degree) South Asian, black Caribbean or Middle Eastern.
Precautions in women with pre existing diabetes
Aspirin 75mg
Review every 2 weeks
Anomaly scan @ 20 weeks
Growth scan every 4 weeks from 28 weeks
Prophylactic LMWH antenatally and for 6 weeks postnatally
Blood sugar fasting <5.3, <7.8 1 hour post meal
Common drugs contraindicated in pregnancy
Contraindicated:
Ramipril
Isotretinoin
Sodium valproate
Caution:
Citalopram (1st trimester - congenital heart disease)
Trimethoprim (1st trimester - interferes with folic acid pathway)
Lamotrigine
Propylthiouracil (liver disease/failure in some pregnancies
Carbimazole (1st trimester - aplasia cutis)
Nitrofurantoin (>36 weeks - haemolytic anaemia)
Maximum dose of metformin?
2500mg OD
Risk factors that increase the chances of shoulder dystocia
Macrosomia Diabetes in pregnancy Previous shoulder dystocia Raised BMI Induction of labour Epidural Instrumental delivery
Pathophysiology of diabetes in pregnancy
Increased insulin resistance
Reduced glucose tolerance
Reduced renal tubular threshold for glucose
Effect of pregnancy on diabetes
Increasing doses of insulin
Worsening retinopathy or nephropathy
Increased hypoglycaemic attacks
Diabetic drugs in pregnancy
Used
Metformin
Insulin
Avoided
Sulfonylureas (glibencamide)
Statins
ACE inhibitors
Hypertension drugs in pregnancy
Used
Labetalol
Nifedipine
Doxasosin
Avoided
ACE inhibitors
Angiotensin II blockers
Diuretics
Haematological drugs in pregnancy
Used
LMWH
Avoided
Warfarin
Epilepsy drugs in pregnancy
Used
Lamotragine
Avoided
Sodium valproate
Phenytoin
Phenbarbitone
Endocrine drugs in pregnancy
Used
Carbimazole
Propylthiouracil
Avoided
Radioactive iodine
Sex hormones
Drugs used in inflammatory conditions in pregnancy
Used
Prednisolone
Sulfasalazine
Mesalazine (5mg folic acid)
Avoided
Methotrexate
Cyclophosphamide
NSAIDS
Maternal effects of diabetes on pregnancy
Increased risk of miscarriage Increased PET Worsening renal damage (hypoalbuminaemia, anaemia) Infection Increased induction rate and LSCS rate
Fatal effects of maternal diabetes on pregnancy
Increased risk of congenital malformations (skeletal, cardiac, NTD)
Unexplained stillbirth
What is the Pederon hypothesis?
Maternal hyperglycaemia leads to foetal hyperglycaemia
Increased production of foetal insulin
Insulin = growth factor
Leads to:
- foetal hypoxia causing haemopoesis and thus polycythaemia and jaundice (splenomegaly)
-macrosomia which is associated with induction, dysfunctional labour, shoulder dystocia, PPH
Can lead to neonatal hypoglycaemia (feeding required 30mins post birth, blood sugars every 2-4 hours)
When to refer to nephrologist?
Urine P/C Ratio >30mg/mmol
eGFR <45
HbA1c, target and significant risk
Aim: <48
Significant risk: >86
When should a baby be delivered (IOL or LSCS) in diabetes?
T1 or T2DM - 37-38+6
Offered prior to 37/40 if possible foetal or maternal complications
GDM - 40+6
When is LSCS offered if shoulder dystocia is a concern?
In diabetes >4.5kg
Normal >5kg
