Endocrine Disorders of Pregnancy Flashcards
What can use an increased serum “total” T4 and T3 levels
increase in serum T4 binding globulin production caused by elevated oestrogen levels
Why do thyroid hormone requirements increase during pregnancy
Increased weight
placental deiodinase activity
transfer of T4 to the foetus
Maternal TSH does not cross the placenta. True or false
True
What thyroid hormones cross the placenta
T3 and T4
At what stage of development does metal TSH appear
around the 10th week of gestation
What are the thyroid hormones important for in development
Cognitive development during early pregnancy
What is hypothyroidism in pregnancy associated with
early pregnancy loss placental abruption pre-eclampsia preterm delivery low birth weight perinatal mortality neuropsychological impairment
What is the ideal TSH level in hypothyroidism which has been diagnosed before pregnancy
TSH level of less than 2.5mU/L
What are hypothyroid patients unable to do
increase their T4 and T3 secretion
What should the dose of levothyroxine be increased by and when
30-50% by 4-6 weeks gestation
What are further dose changes of levothyroxine based upon
serum TSH concentrations
How often should serum TSH be measured
4-6 weeks after conception
4-6 weeks after any change in the dose
at least once each trimester
What should happen to the dosage of levothyroxine after delivery
it should be reduced to pre-pregnancy levels
What is poorly controlled hyperthyroidism in pregnancy associated with
Pregnancy loss premature labour low birth weight pre-eclampsia maternal cardiac failure
Why is it difficult to diagnose hyperthyroidism during pregnancy
many of the symptoms are similar to the non-specific symptoms associated with pregnancy
What is the diagnosis of hyperthyroidism in pregnant women made
based primarily on a serum TSH less than 0.01mU/L and a high serum free T4 and or free T3
What is helpful in making the diagnosis of Graves’ disease during pregnancy
Measurement of TSH-receptor antibodies (TRAbs)
What should Hyperthyroidism due to Graves’ disease or hyper functioning thyroid nodules be treated with
antithyroid drugs
When might a subtotal thyroidectomy be indicated in hyperthyroid women during pregnancy
women who cannot tolerate antithyroid drugs because of allergy or agranulocytosis
When is the optimal timing of surgery
second trimester
Why do some neonates born to women with Graves’ disease have hyperthyroidism
due to the transplacental transfer of TSH receptor stimulating antibodies
What is hyperemesis gravidarum characterised by
nausea
vomiting
weight loss
all during early pregnancy
Describe the levels of T4 and T3 in hyperemesis gravidarum
Serum free T4 is minimally elevated and serum T3 is usually not elevated
What is the treatment for hyperemesis gravidarum
Nothing - it resolves as hCG production falls
IV fluids
anti-emetics and nutritional support
What can cause thyroid enlargement
iodine depletion (due to increased maternal renal clearance and metal uptake of iodine )
What do women with malignant or suspicious cytology require
surgery
What do prolactinomas usually result in
infertility due to the inhibitory effect of prolactin on gonadotrophin secretion
What are patients with microprolactinomas treated with
dopamine agonist prior to pregnancy
When is a dopamine agonist discontinued
as soon as pregnancy has been confirmed
What should be given to a patient with a macroprolactinoma in order to shrink the tumour prior to pregnancy
Cromocriptine or cabergoline
Why is breast feeding contraindicated in women who have neurological symptoms at the time of delivery
They should be treated with a dopamine agonist
Describe the effect of Addison’s disease in pregnancy
The foetus produces and regulates its own adrenal steroids
Therefore, pre-existing primary adrenal insufficiency in the mother is not associated with metal morbidity
Describe the changes of treatment in a pregnant woman with Addison’s to a non-pregnant woman
They are the same
What should be given at the time of delivery in a patient with Addison’s and why
high dose IM hydrocortisone to cover the stress
How might Addison’s disease that has developed in pregnancy present
adrenal crisis particularly at time of delivery
What is the main sign of phaeochromocytoma
Hypertension
paroxysmal headache
sweating
palpitation
How is the diagnosis of phaeochromocytomas in pregnancy made
3 24 hour urine collections for the measurement of catecholamines and fractionated metanephrines
MRI is use for localisation of tumours after confirmation of the diagnosis
What is the treatment for a phaechoromocytoma in a pregnant woman
phenoben`amine (alpha blocker) 10mg BD and increased gradually
What is gestational diabetes mellitus
glucose intolerance with an onset or first recognition during pregnancy
What results in the maternal insulin resistance in gestational diabetes
Increased placental secretion of diabetogenic hormones such as growth hormone, corticotrophin-releasing hormone, human placental lactogen and progesterone
Why does gestational diabetes occur in some women
pancreatic function cannot overcome both the insulin resistance created by these anti-insulin hormones and the increased fuel consumption necessary to provide for the growing mother and foetus
How is gestational diabetes diagnosed
a 75mg 2 hour oral glucose tolerance test
What else should be tested during routine prenatal testing during an assessment of women with diabetes
measurement of glycated haemoglobin urea creatinine and electrolytes TSH free T3 ECG
What is meant by medical nutritional therapy
3 meals and 3 snacks a day
40% carbs, 40% fat and 20% protein
How often should patients check their blood glucose
upon awakening and 1 hour after each meal to evaluate the effectiveness of the medical nutritional therapy
What is the goal of insulin therapy
a fasting blood glucose of less than 5mmol/L
What is poorly controlled diabetes in the first trimester associated with
Miscarriage and congenital malformations
When might earlier delivery be warranted
in the presence of high risk factors such as worsening retinopathy or nephropathy
poor control
pre-eclampsia or restricted metal growth
What are women with gestational diabetes at an increased risk of developing
diabetes after pregnancy
What might worsen in diabetics during pregnancy
diabetic retinopathy
How often should diabetic patients be screened for diabetic retinopathy in pregnancy
during the first trimester and then every 3 months
What can be carried out safely during pregnancy if required in diabetic retinopathy
Laser therapy and virtuous surgery
