Diabetes and pregancy Flashcards
What is gestational diabetes (GDM)?
Diabetes diagnosed in the 2nd or 3rd trimester that was not clearly overt diabetes before pregnancy
What causes insulin resistance in pregnancy?
Placental hormones
(progesterone, human placental lactogen)
Increase insulin resistance to divert nutrients to the foetus
Why does gestational diabetes occur?
If the mother is already insulin resistant before pregnancy, further insulin resistance raises blood glucose too high
What are the complications of pre-existing diabetes (T1DM/T2DM) in pregnancy?
Congenital malformations
Prematurity
Intrauterine growth restriction (IUGR)
Why does gestational diabetes cause macrosomia?
Foetal hyperinsulinaemia
What is the main complication of neonatal hyperinsulinaemia?
Neonatal hypoglycaemia after birth due to continued high insulin levels
What are other foetal complications of GDM?
Polyhydramnios
Intrauterine death
What neonatal complications are associated with diabetes in pregnancy?
(1) Respiratory distress
(2) Hypoglycaemia
(3) Hypocalcaemia
(4) CNS defects
(anencephaly, spina bifida)
(5) Skeletal abnormalities
(caudal regression syndrome)
How is gestational diabetes diagnosed?
75g OGTT (Oral Glucose Tolerance Test) means the patient drinks a solution containing 75 grams of glucose and blood glucose levels are measured before (fasting) and 2 hours after to assess how well the body handles sugar
(1) Fasting glucose ≥5.6 mmol/L
= If blood sugar is 5.6 mmol/L or higher before drinking glucose, GDM is diagnosed.
(2) 2-hour glucose ≥7.8 mmol/L
= If blood sugar is 7.8 mmol/L or higher two hours after drinking glucose, GDM is diagnosed.
What is the memory aid for
5.6 mmol/L = Fasting glucose threshold for GDM
7.8 mmol/L = 2-hour post-OGTT threshold for GDM ?
Diagnosis of GDM is as easy as 5678
What is the most important pre-pregnancy intervention for women with diabetes?
Folic acid 5 mg (higher dose than the standard 400 µg) at least 3 months pre-conception to reduce congenital malformations
Which antihypertensive drugs should be used in pregnancy?
Labetalol, nifedipine, methyldopa. (Avoid ACE inhibitors)
Why is aspirin 150 mg started at 12 weeks in diabetic pregnancies?
To reduce the risk of pregnancy-induced hypertension (pre-eclampsia)
What are the blood glucose targets in pregnancy?
(1) Pre-meal: <4-5.5 mmol/L
(2) 2-hour post-meal: <6-6.5 mmol/L
How is T1DM managed in pregnancy?
Insulin
How is T2DM managed in pregnancy?
Metformin initially, then insulin if needed
How is GDM managed?
Lifestyle changes → Metformin → Insulin if needed
How is diabetes monitored postpartum?
6-week postnatal fasting glucose or OGTT to check for persistent diabetes
What percentage of GDM patients develop Type 2 Diabetes later?
50% within 10-15 years
What is HCG?
hCGstands forhuman chorionic gonadotropin, a hormone produced by the placenta during pregnancy
Where does HCG come from?
Secreted bysyncytiotrophoblastsof the placenta
What use is HCG in practice?
Diagnosing pregnancy (e.g., pregnancy tests)
Human Placental Lactogen (HPL) is secreted from where?
Secreted bysyncytiotrophoblastsof the placenta
What week of pregnancy does organogenesis start?
Starts aroundweek 3–8 of gestation
What are the two most important things to do for antenatal care in people with T1/T2 diabetes?
- Strict glycemic control
= frequent glucose monitoring, use of insulin or adjustments - Folic acid supplementation
= high dose: 5 mg daily before conception and during early pregnancy to prevent neural tube defects
Gestational diabetes usually presents in the first trimester. True or false and why if false?
False
= Gestational diabetes typically develops later, usually in the second or third trimester
Methyldopa in pregnancy is the preferred treatment for blood pressure. True or false and why if false?
True
Folic acid 5mg should be started when a woman knows she is pregnant. True or false and why if false?
False
= Folic acid 5mg should ideally be started before pregnancy, ideally at least one month prior, to reduce the risk of neural tube defects
A woman in early pregnancy with known hypothyroidism should double her thyroxine dose when she finds she is pregnant. True or false and why?
True
= In early pregnancy, the demand for thyroid hormones increases, and women with hypothyroidism may need a higher dose of thyroxine (typically increasing by 25-30%) to maintain normal thyroid levels
A 28-year-old primigravida female of 26 weeks’ gestation presents to the Obstetric Diabetes Clinic following her oral glucose tolerance test last week.
Her test results demonstrate:
(1) Fasting glucose 7.8 mmol/L
(normal range 3.5-5.5 mmol/L)
(2) 2-hour glucose 9.4 mmol/L
What is the most appropriate management?
Initiation of insulin
A 28-year-old primigravida female of 26 weeks’ gestation presents to the Obstetric Diabetes Clinic following her oral glucose tolerance test last week.
Her test results demonstrate:
(1) Fasting glucose 7.8 mmol/L (normal range 3.5-5.5 mmol/L)
(2) 2-hour glucose 9.4 mmol/L.
Why wouldn’t diet and lifestyle changes be the first line management?
Lifestyle changes is indicated if the fasting plasma glucose level is below 7 mmol/l at the time of diagnosis
What BMI cut off defines obesity?
30
A 28-year-old primigravida female of 26 weeks’ gestation presents to the Obstetric Diabetes Clinic following her oral glucose tolerance test last week.
Her test results demonstrate:
(1) Fasting glucose 7.8 mmol/L (normal range 3.5-5.5 mmol/L)
(2) 2-hour glucose 9.4 mmol/L.
Why wouldn’t metformin be the first line of management?
Metformin is the first-line treatment provided if the fasting plasma glucose level is below 7 mmol/l following a 2-week trial of altering diet and exercise
What is the name of a large baby in utero?
Macrosomia
What is the most commonest form of congenital malformation seen in diabetic pregnancy?
Macrosomia
A baby in the postnatal ward who was delivered 10 hours ago has just had a generalised seizure lasting 2 minutes. There were no complications during the vaginal delivery and the baby’s birthweight was 4.8kg. A newborn baby check carried out was unremarkable and prior to the seizure the baby appeared well with an APGAR score of 10 at 5 minutes.
What condition did the mother likely suffer from during pregnancy? and why is tat your answer?
Gestational diabetes
= Macrosomia (birthweight >4kg) and neonatal seizures are both complications of poorly controlled maternal diabetes during pregnancy
A 30-year-old woman comes to the clinic at 24+5 weeks gestation. She has a BMI of 32kg/m^2 and a family history of diabetes mellitus. As such, you decide to test her fasting glucose and find it is 6.8mmol/L (normal range 3.5-5.5 mmol/L)
What is the most appropriate initial management? and why isn’t it insulin or metformin?
Two-week trial of diet and exercise
= In those with a fasting glucose of >5.6mmol/L but <7mmol/L, NICE recommend a trial of diet and exercise for two weeks
What are the risk factors for MODY
(1) Ethnic backgrounds with a high prevalence of type 2 diabetes (eg, Middle Eastern, South Asian, and Afro-Caribbean)
(2) Prior history of GDM
(3) Prior delivery of macrosomic babies (>4.5kg)
(4) History of stillbirth or perinatal death
(5) Maternal obesity (BMI>30)
(6) Diabetes in first-degree relatives
What are the Foetal Complications for MODY
(1) Macrosomia (birthweight >4kg)
(2) Increased risk of sacral agenesis in the developing foetus
(3) Pre-term delivery
(4) Neonatal hypoglycaemia
(5) Long-term risk
